Electrical Safety - Plant Services

TECHNOLOGY REPORT

Electrical Safety

TECHNOLOGY REPORT: Electrical Safety 2

TABLE OF CONTENTSElectrical Safety Survey Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

Are you the 1 in 4 who thinks your plant is not up to code?

Are your electrical workers qualified? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Utilizing only Qualified Persons to perform electrical work can greatly

reduce safety risk while increasing electrical system and equipment reliability

Beat the challenge of safe, reliable cooling to modern plant enclosures . . . . . . . . . 18

Vortex cooling systems can deliver efficient cooling to plant electronics

in both ordinary and hazardous locations

Achieving electrical safety by design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

PPE is essential but it should be the last line of defense in an electrical hazard

NFPA 70E 2018: What you need to know to protect yourself . . . . . . . . . . . . . . . . . .29

In 2014, exposure to electricity resulted in 154 workplace fatalities and

1,850 cases with days away from work in 2014

Electrical equipment reliability with ultrasound and infrared . . . . . . . . . . . . . . . . . . 33

For inspection of energized electrical equipment, ultrasound instruments

are joining the electrical inspector’s toolbox alongside noncontact infrared cameras

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Plant Services readers have regularly weighed in on

two key research topics – predictive maintenance

programs and workforce issues. Your responses have

shed additional light on actions and attitudes that are going

on in real time on your plant floor. For 2018, the Plant Services

editors wanted to add a third research project into the mix,

and the choice of topic was an easy one to make: electrical

safety. No other topic is as key to plant best practices as safety

or as important to team morale. And in terms of electrical

safety specifically, few other plant hazards are as sudden or as

invisible as electrical risks, especially arc flash. In fact, close to

one-quarter of survey respondents said that they had been involved in an arc flash event, and

60% reported knowing someone who has been involved in such an event.

Future follow-up surveys will help reveal electrical safety trends over time; for now, the

data provide an insightful and current snapshot of electrical safety in the places where you

spend a large chunk of your time. Read on for the survey highlights, and then download the

full set of 2018 Electrical Safety survey data at http://plnt.sv/1802-ES.

Here’s hoping your plant is a safe plant.

Electrical SafetySurvey ResultsAre you the 1 in 4 who thinks your plant is not up to code?

Thomas Wilk, editor in chief

ARE YOU THE 1 IN 4 WHO THINKS YOUR PLANT IS NOT UP TO CODE?

electrical safetySURVEY RESULTS


S M A R T S O L U T I O N S F O R M A I N T E N A N C E & R E L I A B I L I T YF

EB

RU

AR

Y 2

01

8

Doc Palmer tackles The Most Dangerous Metric / P.21

The link between PID controller data and asset reliability / P.23

Current affairs: What's causing your high motor current? / P.34

Change your perception of who owns reliability / P.42

PS1802_01_Cover2.indd 1 2/2/18 12:17 PM

http://plnt.sv/1802-ES



BACKGROUND / UP TO CODE?This year’s electrical safety survey is de-

signed as a benchmark study, with ques-

tions balanced across electrical incidents,

safety gear and technology, training and

certifications, and an analysis of the most

common obstacles to achieving a safety-

first, safety-always culture.

The survey was open from Oct.-Dec. 2017

and attracted nearly 200 responses from

Plant Services readers. Figure 1 illustrate the

types of jobs that survey respondents hold,

and Figures 2 and 3 show their levels of

electrical expertise and the types of industry

certifications they hold, respectively. Other

questions asked where you fit generation-

ally (about half of respondents are Boomers

and older, and half are Gen X and Millennial);

the size of your maintenance/reliability team

(about half were between 5-50 people); and

the number of plants your organization man-

ages (close to 70% of respondents work for

organizations of five plants or fewer).

One number in particular jumped out: 71% of

respondents have at least 16 years of expe-

rience doing electrical repairs and trouble-

shooting. This year’s survey respondents

are clearly an experienced bunch – a trend

that extends to professional certifications as

well: Nearly half of survey respondents have

earned at least one professional certification.

There also was one question on the survey

designed to uncover your overall perception

of electrical safety at your facility: Do you

consider your plant electrically up to code?

As Figure 4 indicates, 25% of respondents

replied “no”; that share that did not vary

significantly across any of the demographic

groups – job title, vertical, generational, plant

/ team size, experience or certification level

– identified in the initial survey questions.

Plant manager

Maintenance manager

Maintenance engineer

Maintenance technician

Reliability engineer

Reliability technician

Controls engineer

Plant engineer

Sales/marketing

Applications engineer

IT

Corporate executive

What is your primary job function?

Figure 1

Figure 2

How long have you been doing electrical repairs or troubleshooting?

0-1 year

2-5 years

6-15 years

16+ years



This number maps interestingly onto two oth-

er survey questions. The first of these asked

about your facility’s average time between

electrical incidents. As Figure 5 shows, 25% of

respondents said the average time between

incidents at their plant was six months or less,

and again the data did not vary significantly

across demographic categories.

The second question asked about whether

your facility engages in near-miss reporting,

and 72% reported having a formal near-miss

reporting program in place. The other 28%

indicated that either an informal program

exists (18%) or no program is currently in

place (10%).

TECHNOLOGYThis year’s survey asked six specific questions

on the types of electrical safety technology

that are currently in use at your facility; these

data are available in the full downloadable

report (http://plnt.sv/1802-ES). Some of the

data highlights include the following.

Safety Technologies. The most commonly

deployed safety technologies reported by

respondents are limit (93%) and interlock

(91%) switches, followed by single-function

relays (93%), motor control devices (90%),

PLCs and drives (87%), overcurrent protec-

tion devices (86%), and proximity devices

such as light curtains (84%).

In fact, the only technology option listed in

this question being used by less than 70%

ASNT Level I Thermographer (5.9%)

ASNT Level II Thermographer (4.3%)

ASNT Level III Thermographer (3.2%)

CMRP through SMRP (5.9%)

IAEI Certified Electrical Inspector (2.7%)

NFPA Certified Electrical Safety Compliance Professional (5.3%)

NFPA Certified Electrical Safety Worker (5.3%)

NICET Electrical Power Testing (3.2%)

State Licensed Journeyman or Higher (17.6%)

None (52.4%)

Other (13.9%)

Which certifications do you currently hold?

Figure 3

Figure 4

Do you consider your plant electrically up to code?

Figure 5

52% 365 + days

6.4% 0-30 days8.5% 31-90 days10.6% 91-180 days22.7% 181-365 days

What is your facility’s average time between electrical incidents?




of survey respondents is IR windows/view-

ports: only 37% of respondents are current-

ly using them, and 49% report they have no

plans to do so in the future.

Personal Protective Equipment. When

asked what types of PPE are available for

use, respondents cited safety glasses (97%)

and safety shoes (96%) the most, followed

by insulating gloves (87%), leather protec-

tor gloves (86%), face shields (86%), and

hard hats (85%). The least-available types

of equipment all fell into the category of

insulating equipment: insulating sleeves

(55%); insulating live-line tools (i.e., hot-

sticks, switchsticks, shotgun sticks, 54%);

and IPE such as line hoses, rubber hoods,

and rubber blankets (50%). Also, about 40%

of respondents indicated that there were no

plans in place to make these types of insu-

lating equipment available to employees.

IR Cameras and Digital Technologies. Nearly

75% of respondents indicated that they use

portable IR cameras in their facility; this data

point maps well onto the 72% of respon-

dents who engage in IR thermography as

part of a predictive maintenance program.

Interestingly, there did not seem to be a con-

nection between respondents’ willingness to

use portable IR cameras and their use of IR

windows: about two thirds of those who said

they had no plans to deploy IR windows still

use portable IR cameras on the job.

When it comes to wearable safety systems

and sensors, just 1 in 3 respondents said

they currently use wearables, with 51% re-

porting that currently there are no plans to

implement this technology.

Finally, two questions asked about the degree

to which internet-enabled technologies are in

use, with 44% reporting that they are using

the IoT to monitor their electrical systems and

39% using the IoT to report on system health.

Outsourcing. Not every plant has the full-

time resources to conduct electrical work

– a fact that may affect uptake of safety

technologies. For this question, 77% of re-

spondents said that they outsource installa-

tion work; 63% and 61% said they outsource

testing and repair work, respectively; and

43% said that they outsource the condition

monitoring of their electrical systems (50%

keep it in-house).

ELECTRICAL SAFETY CHALLENGESFor Plant Services readers, the results

shown above in Figure 6 are especially

worth noting. Of the safety challenges

listed as options in this year’s survey, the

top trouble spot when it comes to electri-

cal safety is poor or ineffective equipment

maintenance, with almost 11% of respon-

dents rating it as a high challenge.

In fact, when the “medium” and “high”

categories are combined, two challenges

emerge as most pressing: (1) poor or inef-

fective equipment maintenance, 39%; and



(2) poor or ineffective training, at 33%.

(Equipment grounding was close behind

maintenance in the “high” category at 9.3%,

but fewer respondents considered it a me-

dium challenge.)

On the maintenance side, the survey asked

about the type of predictive maintenance

program currently in place, with respon-

dents indicating that they were using a

combination of methods to monitor their

electrical systems. The four most-used

technologies are IR thermography (72%),

oil analysis (70%), motor testing (67%), and

vibration analysis (65%), with predictive

modeling cited as the currently least-used

method (16%).

Two additional survey questions help add

context to respondents’ concern over train-

ing. The first question asked about the fre-

quency of training, and 10% of respondents

indicated that training is not required at all

at their facility. A further 27% indicated that

training is required no more than every two

years. The better news is that a comfort-

able majority (56%) reported that they are

required to take annual training, such as an

OSHA refresher course; in addition, 7.4% of

respondents engage in quarterly training.

The survey also asked about types of

training methods, with 71% of respondents

indicating that traditional on-site technical

training is employed, about 56% reporting

the use of online courses or webinars, and

10% reporting that augmented or virtual

reality is now being used at their facility.

The good news is that three challenges are

clearly at the bottom of the list: poor co-

ordination with external agencies such as

OSHA (21%), poor or ineffective PPE (15%),

and contact with overhead or underground

electrical lines (9%).

Not a factor (%) Low (%) Medium (%) HIgh (%)

Poor coordination with internal departments (i.e., EH&S) 41.4 31.4 21.4 5.7

Poor coordination with external agencies (i.e., OSHA) 51.4 27.9 15.0 5.7

Poor / ineffective training 35.7 31.4 24.3 8.6

Poor / ineffective PPE 55.7 29.3 12.1 2.9

Poor / ineffective dust mitigation 35.0 37.9 20.0 7.1

Poor / ineffective lockout / tagout 45.7 30.7 16.4 7.1

Poor / ineffective equipment maintenance 27.1 34.3 27.9 10.7

Poor / ineffective equipment grounding 42.9 35.0 12.9 9.3

Poor / ineffective incident reporting 45.7 30.7 18.6 5.0

Loose electrical connections 23.6 50.0 22.9 3.6

Slips, trips, falls 21.4 52.1 18.6 7.9

Contact with overhead or underground electrical lines 66.4 25.0 5.7 2.9

Rate the following electrical safety challenges at your facility.

Figure 6



When asked an open-ended question about

the one thing they would do to improve

electrical safety, respondents reported the

following:

• “Training for nontechnical team members

on their electrical safety, how to recog-

nize hazards and avoid them.”

• “Teach everyone in the facility about the

dangers of electricity. This could be just

as useful at home as it is at work. Most

employees don’t understand the dangers

involved in electricity.”

• “Make sure technicians understand the

culture-of-safety value, through consid-

ering the value of what this contributes

inside the organization.”

• “Update disconnects and starters.”

• “Modernize with new technology.”

• “Find improved devices for wash-down

areas.”

• “Need more training on test procedures.”

• “Getting trained and updated on new

electrical safety codes.”

• “Re-enactment of near misses.”

• “Include a simple one-page laminated

card that indicates the areas of high elec-

trical danger.”

• “Replace old and worn out MCCs.”

• “Learn and use ultrasonic technology.”

• “Do an arc flash study, but upper manage-

ment will not fund.”

• “Better guarding, consistently applied

at every station. Set up a formal training

program for OSHA and NFPA 70E. Safety

training requiring passing the course and

enforcement of PPE rules and LOTO rules.”

INCIDENTS AND TRAININGThe final section of the survey asked about

electrical incidents at your facility as well

as your facility’s policies on energized work

and the types of training available. As noted

on Figure 5, about 25% of respondents

indicated that it had been six months or less

since their last electrical incident.

Figure 7 provides some background data

that adds context to responses about the

frequency of electrical incidents. Specifical-

ly, 28% of respondents also have been part

of an OSHA investigation, and 28% also said

that their facilities have either an informal

near-miss reporting program or none at all.

Have you ever been part of an OSHA

investigation? 72%NO

28%YES

Does your facility have a policy in place on

energized work?24%NO

76%YES

Have you received training on NFPA 70E?

32%NO

Up to expected changes in 70E 2018 23% Up to 70E 2015 35%

Up to 70E 2012 10%

68%YES

Figure 7



On the question of whether your facility has

a policy in place on energized work, 24%

responded “no.” For those that do have

policies in place, the vast majority of re-

spondents (85%) indicated that the policy

was communicated during training, with

the remaining 15% balanced between online

and public notices (email, bulletin boards,

plastic sheets).

Finally, it was striking that the share of

respondents who reported no training on

NFPA 70E was 33%. The better news is that

about 23% of respondents had already been

trained by the end of last year on expected

changes in 70E 2018.

The survey also asked four specific ques-

tions on arc flash training and incidents; all

are captured in Figure 8. It’s interesting to

note that ARC flash studies are performed

on gear far less often than training on ARC

flash is provided to respondents; as one

respondent mentioned earlier, budgetary

constraints may play a role here.

For this first Electrical Safety survey, we

also added two questions on whether you

(23%) or someone you know (60%) has

been involved in an arc flash incident, and

these data also are reported in Figure 8.

However, as one respondent noted, both of

these questions would deliver more insight

if further options were available for re-

spondents to select beyond “yes” and “no”;

for example, these options could include

whether or not the incident involved peo-

ple, or people but no injuries, or incidents

with lost time.

If you’re interested in viewing the full data set, please

download it at http://plnt.sv/1802-ES, and then consider

sending your thoughts to [email protected]. We will be

preparing an industry feedback article on this survey

that will appear a future issue, and we would value your

insights.

Have you been trained specifically for

ARC flash? 23%NO

77%YES

Have you done an ARC flash study

on your gear?43%NO

57%YES

Have you ever been involved in an arc flash

incident?77%NO

23%YES

Do you know someone who has been involved

in an arc flash incident?40%NO

One person 36% 2-5 People 21%

More than five people 3%

60%YES

Figure 8


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There is a serious misconception throughout industry that a licensed Journeyman or

Master Electrician constitutes a Qualified Person. This is not necessarily true.

A Journeyman or Master license is obtained through a required number of years working

under a licensed electrician (depending on the state, county, or municipality requirements)

and passing a National Electrical CodeÆ (NEC) exam. For example, a licensed Master

Electrician may have 10 years of hands-on field experience and qualifications in wiring

residential buildings; however, they would not be experienced or qualified to work in a

manufacturing facility and therefore could not be hired as a Qualified Person. The following

definitions will make this clear.

The OSHA 29 CFR 1910.399 defines a Qualified Person as: “one who has received training

in and has demonstrated skills and knowledge in the construction and operation of electric

equipment and installations and the hazards involved.”

OSHA provides additional information on what constitutes a Qualified Person in the follow-

ing notes to the definition:

Note 1 to the definition of “qualified person”: Whether an employee is considered to be a

“qualified person” will depend upon various circumstances in the workplace. For example, it

Are your electrical workers qualified?Utilizing only Qualified Persons to perform electrical work can greatly reduce safety risk while increasing electrical system and equipment reliability

By Dennis Neitzel, AVO Training Institute



is possible and, in fact, likely for an individ-

ual to be considered “qualified” with regard

to certain equipment in the workplace, but

“unqualified” as to other equipment. (See

1910.332(b)(3) for training requirements

that specifically apply to qualified persons.)

Note 2 to the definition of “qualified

person”: An employee who is undergoing

on-the-job training and who, in the course

of such training, has demonstrated an ability

to perform duties safely at his or her level of

training and who is under the direct supervi-

sion of a qualified person is considered to

be a qualified person for the performance of

those duties.”

OSHA and NFPA 70E have provided strict

requirements for training that go hand-in-

hand with the qualification of an employee.

The following information is provided in or-

der to clarify the OSHA mandates for train-

ing qualified workers in the electrical field.

OSHA 29 CFR 1910.332, Training, requires a

Qualified Person to be trained in “the safe-

ty-related work practices that are required

by 1910.331 through 1910.335 that pertain

to their respective job assignments.” OSHA

goes on to require:

Qualified Persons (i.e., those permitted to

work on or near exposed energized parts)

shall, at a minimum, be trained in and famil-

iar with the following:

• The skills and techniques necessary to

distinguish exposed live parts from other

parts of electric equipment.

• The skills and techniques necessary to

determine the nominal voltage of exposed

live parts, and

• The clearance distances specified in

1910.333(c) and the corresponding volt-

ages to which the qualified person will be

exposed.

Note 1: For the purposes of 1910.331 through

1910.335, a person must have the training

required by paragraph (b)(3) of this section

in order to be considered a qualified person.

Note 2: Qualified persons whose work on

energized equipment involves either direct

contact or contact by means of tools or ma-

terials must also have the training needed to

meet 1910.333(C)(2).

OSHA 1910.332 also states the following

concerning the training required for quali-

fied employees: “The training requirements

contained in this section [1910.332] apply to

employees who face a risk of electric shock.

... Note: Employees in occupations listed in

Table S4 face such a risk and are required to

be trained. Other employees who also may

reasonably be expected to face comparable

risk of injury due to electric shock or other

electrical hazards must also be trained.”

OSHA 29 CFR 1910.269(a)(2)(i), as well as



NFPA 70E, 110.2 requires employees to be

trained in and familiar with the safety-related

work practices, safety procedures, and other

safety requirements as it pertains to their

respective job assignments. OSHA also re-

quires employees to be trained in any other

safety practices, including applicable emer-

gency procedures that are related to their

work and are necessary for their safety.

Qualified employees are required to be

trained and competent in:

• Skills and techniques necessary to distin-

guish live parts for other parts

• Skills and techniques necessary to deter-

mine the nominal voltage

• Minimum approach distances to live parts

• The proper use of:

o Special precautionary techniques

o Insulating and shielding materials

o Insulated tools and test equipment

o Job planning

A person must have this training in order

to be considered a Qualified Person. They

also require the employer, through regu-

lar supervision and annual inspections, to

verify that employees are complying with

the safety-related work practices. Addi-

tional training or retraining may also be

required if:

• The supervision or annual inspection indi-

cate non-compliance with work practices

• New technology

• New types of equipment

• Changes in procedures

• Employee is required to use work prac-

tices that they normally do not use

Tasks that are performed less often than

once per year would require refresher or re-

training before the performance of the work

practices involved. This retraining may be

as simple as a detailed job briefing prior to

the commencement of the work, or it may

require more in-depth classroom instruction

along with on-the-job training.

All training is required to establish employ-

ee proficiency in the work practices and

Occupation

Blue collar supervisors.(1)

Electrical and electronic engineers.(1)

Electrical and electronic equipment assemblers.(1)

Electrical and electronic technicians.(1)

Electricians

Industrial machine operators.(1)

Material handling equipment operators.(1)

Mechanics and repairers.(1)

Painters.(1)

Riggers and roustabouts.(1)

Stationary engineers.(1)

Welders.

Footnote(1): Workers in these groups do not need to be trained if their work or the work of those they supervise does not bring them or the employees the supervise close enough to exposed parts of electric circuits oper-ating at 50 volts or more to ground for a hazard to exist.

Table S-4 . Typical occupational categories of employees facing a higher than normal risk of electrical accident .



procedures. In fact, OSHA 1910.269 requires

the employee to demonstrate proficiency

in the work practices involved before the

employer can certify that the employee

has been trained. Note the statement that

requires the employee to demonstrate pro-

ficiency in the work practices involved. The

only way the employee can demonstrate

proficiency is through a written exam and/

or to actually do the work after receiving

or as part of the training. Hands-on training

would be required in order to accomplish

this OSHA requirement.

OSHA 1910.332 states: “The training re-

quired by this section shall be of the class-

room or on-the-job type. The degree of

training provided shall be determined by

the risk to the employee.” NFPA 70E goes

on to state that “the training shall be class-

room, on-the-job, or a combination of both,

and that retraining shall be performed at

intervals not to exceed 3 years.” All training

and retraining must be documented.

One of the most important aspects of elec-

trical safety is to ensure that all employees

who are or may be exposed to energized

electrical conductors or circuit parts are

properly trained and qualified. In addition

to the requirements stated above from

OSHA, NFPA 70E 110.2, Training Require-

ments, states that employees are required

to be “trained to understand the specific

hazards associated with electrical energy,”

“the safety-related work practices,” and

“procedural requirements.” These training

requirements are necessary to help protect

employees from the “electrical hazards as-

sociated with their respective job or task

assignments” as well as to “identify and un-

derstand the relationship between electrical

hazards and possible injury.”

OSHA 1910.269(a)(2) also states that “the

training shall establish employee proficien-

cy in the work practices required by this

section and shall introduce the procedures

necessary for compliance with this section.

The employer shall certify that each em-

ployee has received the training required

by paragraph (a)(2) of this section. This

certification shall be made when the em-

ployee demonstrates proficiency in the

work practices involved and shall be main-

tained for the duration of the employee’s

employment.”

According to OSHA, Qualified Persons are

intended to be only those who are well ac-

quainted with and thoroughly conversant

in the electric equipment and electrical

hazards involved with the work being per-

formed. OSHA and NFPA are consistent in

their requirements for training and qualify-

ing employees to perform work on electri-

cal equipment and systems. As can be seen

by the above statements from NFPA 70E

and OSHA, proper training is a vital part of

the worker’s safety and proficiency, as well

as reducing risk to the employee; an em-

ployee, in order to be considered a quali-



fied person, must receive extensive train-

ing. The goal of any training program is to

develop and maintain an effective and safe

work force.

Electrical power systems today are often

very complex. Protective devices, controls,

instrumentation, and interlock systems de-

mand that technicians be trained and quali-

fied at a high technical skill level. Safety and

operating procedures utilized in working on

these systems are equally as complex re-

quiring technicians to be expertly trained in

all required skills, as well as safety practices

and procedures. Utilizing only Qualified Per-

sons to perform electrical work can greatly

reduce the risk to the safety of employees,

as well as increasing reliability of the electri-

cal system and equipment.

Dennis K. Neitzel, is director emeritus of

AVO Training Institute (www.avotraining.

com). Dennis has 45 years experience in

Electrical Utility, Industrial facility, and shipyard/ship-

board electrical equipment and systems maintenance

and testing experience, with an extensive background

in electrical safety and power systems analysis. He is

an active member of IEEE, ASSE, AFE, IAEI, and NFPA.



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more dependent on sophisticated microprocessors, PLCs, and VFDs, the need for proper

heat dissipation has become crucial to keep controls protected. Compact, multifunction

electronic controls are extremely sensitive to heat and contamination: Excessive heat

causes components to “cook”, digital displays to misread, controls to drift, and breakers to

trip below their rated loads. Tightly packed enclosures and panels restrict airflow, resulting

in rapidly rising internal temperatures, thermal runaway, and increasing control failures. The

result often is lost productivity from machines and production line shutdowns.

To reduce enclosure temperatures and prevent failure of high density controls, the inter-

nal enclosure temperature must be lowered to below the room temperature. Research by

control system manufacturers has shown that for each 18F° (10C°) increase in temperature,

online production shutdowns occur twice as often, increasing the failure rate of electronics

by 40 percent.

Beat the challenge of safe, reliable cooling to modern plant enclosuresVortex cooling systems can deliver efficient cooling to plant electronics in both ordinary and hazardous locations

By Steve Broerman, ITW Vortec



Heat dissipation by forced

convection (fan cooling) is

the most frequently used

method of cooling. For

enclosures located in ordi-

nary locations – NEMA 12,

4, and 4X environments, for

example – forced-air fan

cooling (and refrigerant-

based air conditioning) is

usually selected by design-

ers because fans are rela-

tively inexpensive and easy

to install. Unfortunately,

the factory air pulled into

the enclosure by fans often

contains just enough nearly

invisible oil aerosols or

other contaminants to coat

the surfaces of sensitive,

expensive electronic boards

in control enclosures.

Additionally, thermal test-

ing has proven that natu-

ral convection cooling is

not adequate for today’s

smaller, high power den-

sity enclosures. Forced

air cooling systems can

provide heat transfer rates

that are ten times greater

than those achievable with

natural convection and

radiation, but even those

rates are not adequate to

cool electronic components

when they are located in

the many plant environ-

ments where ambient

temperatures can often

exceed 90°F (32°C). (Most

manufacturers of electronic

components specify maxi-

mum operating conditions

of 104°F (40°C) and 90

percent humidity for prop-

er operation.)

For enclosures located in

hazardous locations, cool-

ing solutions are even more

limited. Specifically, while

refrigerant-based mod-

els can be built for hazloc

environments, they are very

expensive initially and costly

to maintain, and their large

physical size can limit where

these systems can be de-

ployed.

Vortex cooling offers

safe and reliable alterna-

tives to the problems with

these conventional cooling

methods. A vortex enclo-

Figure 1 . A vortex tube spins compressed air to produce hot and cold air streams, generating temper-atures down to 100°F below inlet temperature .



sure cooler uses a vortex tube to convert a

filtered compressed air supply into refriger-

ated air without the use of electricity, am-

monia, or other refrigerants. The vortex tube

creates cold and hot air by forcing com-

pressed air through a generation chamber

that spins the air centrifugally along the in-

ner walls of the tube at a high rate of speed

(1,000,000 rpm) toward a control valve.

A small percentage of the hot high-speed air

is permitted to exit at the control valve. The

remainder of the (now slower) airstream is

forced to counter-flow through the center of

the high speed airstream, giving up heat as

it travels through the center of the genera-

tion chamber before it finally exits through

the opposite end as cold air. This air is

discharged at low pressure and low velocity

into the enclosure, while the hot air in the en-

closure is vented outside the enclosure box

through an integral relief valve.

There are no moving parts in a vortex tube,

so the systems are reliable, inherently safe

and have low maintenance requirements (see

Figure 1). The relief valve, baffling, and cooler-

to-enclosure seal maintains the integrity of

NEMA rated boxes in ordinary locations.

Vortex cooling systems are an option for

cooling enclosures located in hazardous

locations because they are inherently safe

when used in areas with temperature clas-

sifications of T4 or higher. There are no

electrical requirements and no moving parts

Common questions about vortex coolers.

1 . Are vortex coolers suitable for hazard-ous locations? Yes, newer models are

approved for Class I, II and III Division 2 or

Zones 2 and 22 locations when used with

an approved purge system. All models

have a temperature classification of T4.

2 . My Freon air conditioner is located near an oven and in the summer it “cuts out” when ambient temperatures get too high . Can I effectively use a vortex cooler here? Yes, vortex coolers will

operate trouble-free in extreme tempera-

tures and in dirty or otherwise inhos-

pitable environments. As long as the

compressed air supply is kept properly

filtered and dried, a vortex cooler will

lower the incoming compressed air sup-

ply to 40 to 50°F (22 to 28°C) or more.

Be sure to avoid running the compressed

air supply near the oven.

3 . I currently use a filter-fan to draw air into the enclosure, but it cannot keep the controls cool enough in the hotter summer months . Can I install a vortex cooler and operate it with the fan during those hot months? No, not efficiently.

The fan will continue to pull in warmer

humid air. The humidity in the ambient air

will condense on the much colder vortex

cooler components, causing damaging

water droplets to form. You must remove

the fan and filter and seal the openings in

the enclosure to prevent ambient air from

entering the enclosure. The fan can be

located inside the enclosure, if desired, to

circulate the cold air.



to generate electrical charges. The only

potential ignition source is the hot surface

at the hot exhaust: When supplied with

compressed air that does not exceed 120°F

(49°C), vortex coolers are approved for

Class I, II and III Division 2, Zone 2 and 22 or

Zone 1 and 21 locations and can be used in

ambient temperatures up to 175°F (80°C)

when used with an approved purge system.

The cooled air that is introduced into the

enclosure is filtered and dried to 5 microns

before it enters the vortex cooler, creat-

ing a clean, cool, and controlled environ-

ment inside the enclosure and helping to

keep controlled processes up and running.

An added benefit is that the vortex cooler

produces a slight positive pressure inside the

enclosure to keep out dust and dirt. Hazard-

ous location models rely on a purge system

to maintain safe enclosure pressures when

the vortex cooler is not operating. An inte-

Figure 2 . Schematic of a vortex cooling system top-mounted on enclosure (example purge sys-tem also shown for reference) .

Common questions about vortex coolers.

4 . Is maintenance required? Because

vortex coolers have no moving parts,

they are reliable and require little main-

tenance. It is only necessary to change

elements in the compressed air filter at

regularly scheduled intervals. A mini-

mum interval of six months is recom-

mended; however, the level of cleanli-

ness of the compressed air supply will

determine the change frequency of the

filter element. If a dirty filter element

reduces the pressure available at the

vortex cooler, the air consumption and

the cooling capacity will drop. Mechani-

cal thermostat models require 90 to 100

psig (6.2 to 6.9 bar) to operate properly.

5 . The components in my purged con-trol panel are designed for ordinary locations and the panel is located in a Class I, Div . 2 hazardous location . However the ambient temperature is greater than the design conditions and the controls are malfunctioning during the hot summer months . Can I use an “ordinary location” vortex cooler or is a hazardous location model neces-sary? A hazardous locations model is

required. Although the components are

safe when enclosed in a purged and

pressurized enclosure, the vortex cooler

must be able to maintain the Class and

Division rating of the panel. In addi-

tion, the size of the spark arrestor vent

may need to be increased to accept the

additional cool air flow from the vortex

cooler so desired enclosure pressure is

not exceeded.



gral check valve keeps the enclosure sealed

when the unit is not cooling so the purge

system maintains enclosure pressure (see

Figure 2).

By using an internal vortex tube to convert

factory compressed air into a clean, dry, low

pressure cold airstream that is distributed

throughout the enclosure, vortex cooling

systems provide efficient, safe and reliable

enclosure protection from heat and dirt

related problems for electronics in ordinary

and hazardous locations.

Steve Broerman is an Engineer at Vortec

(ITW Air Management, www.vortec.com)

and has spent the last 33 years passion-

ately developing vortex tube solutions for thousands of

diverse applications. When he is not serving his cus-

tomers, he enjoys tooling around in his restored 1972

Triumph TR6.


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According to the U.S. Bureau of Labor Statistics the two most common electrical

hazards in industrial environments are electric shock and arc flash. The Electrical

Safety Foundation International (ESFI) reported that there were 1,640 non-fatal

electrical injuries and 154 electrical fatalities in the United States in 2016.

Personal Protective Equipment (PPE) is essential but it should be the last line of defense in

an electrical hazard. The ANSI Z10/CSA Z1000 Occupational Health and Safety risk control

hierarchy (see Figure 1) lists PPE as the least effective safeguard for arc-flash risk. The best

approach is to design safety into the plant’s electrical system from the start. Cost can be an

obstacle, but electrical incidents have a huge impact on a plant’s bottom line both directly

and indirectly.

Implementing the Hierarchy of Controls could reduce both the risk and incidence of electri-

cal hazards. This more proactive approach can be used to tackle electrical safety, and elec-

trical systems of the future will have safety designed right into them.

Safety control points are spread out across a plant’s electrical infrastructure, from switch-

gear to motor control centers or equipment such as submersible pumps. While younger

workers are at higher risk of electrical injury, older facilities often have grandfathered, dated

equipment that is no longer compliant with best safety practices. It may not be practical

Achieving electrical safety by designPPE is essential but it should be the last line of defense in an electrical hazard

By Dean Katsiris and Dave Scheuerman, Littelfuse, Inc.



to replace whole parts of

the system but upgrading

key safety components will

improve safety.

Upgrading these compo-

nents doesn’t have to be

difficult or expensive. Table

1 shows what components

can be designed into an

electrical system to address

the safety control points as-

sociated with the Hierarchy

of Controls.

RISK HIERARCHY: ENGINEERING CON-TROLS There are more workers are

killed each year by electric

shock than arc flash. One

of the most effective ways

to protect against electric

shock is to utilize a Ground-

Fault Circuit Interrupter

(GFCI) designed towards the

UL 943C Standard. Industrial

GFCIs have a higher trip level

than residential GFCIs to

meet the needs of industrial

applications while still oper-

ating within the UL943 trip

curve to protect personnel.

NFPA 70E (Standard for

Electrical Safety in the

Workplace), emphasizes

PPE and labeling. There are

many options available in

both new design and ret-

rofits to reduce arc-flash

energy. From designing in a

more distributed power sys-

tem with smaller transform-

ers (thus limiting available

energy) to arc-resistant

switchgear, to insulated

bus bars, arc-flash relays,

high-resistance grounding,

current-limiting fuses, and

instantaneous trips, there

are no shortage of options

for engineering controls

that provide a higher level

of safety.

Arc-flash relays are a rela-

tively simple way to limit

arc-flash incident energy at

either the design phase or in

retrofit applications. An arc-

flash relay detects the high-

intensity light an arc-flash

gives off and rapidly initiates

a trip at the circuit breaker.

The fastest arc-flash relays

available today can initiate a

trip in less than 1ms.

Current-limiting fuses are an

inexpensive and easy way

to limit the current or ener-

gy available to a panel dur-

ing a short circuit. Because

the amount of thermal

energy released in an arc-

flash is dependent on both

the current available and

the time during which the

arc continues (expressed

as I2t), any reduction to the

duration of the fuse’s arcing

will help in establishing a

safer working environment.

Figure 1 . Hierarchy of controls .



Perform an arc-flash risk assessment to

identify the arc-flash hazard at each electri-

cal panel or piece of equipment. NFPA 70E

(Standard for Electrical Safety in the Work-

place) states that every workplace should

perform an arc-flash risk assessment.

RISK HIERARCHY: SUBSTITUTION Renewable fuses (UL Class H) have not

been permitted for new applications since

2005 yet are still available. Renewable

fuses should be replaced with modern fuses

wherever they are found. Current-limiting

fuses, discussed in the previous section, are

the appropriate replacement choice.

Conventional fuses have a significant draw-

back: a blown fuse looks just like a good

one. If a fuse blows, a worker must get into

the panel and use a voltmeter to determine

which fuse is open. This troubleshooting

often takes place while the power is on,

exposing the worker to the risk of shock

and arc flash. A solution is to substitute

older fuse designs with newer indicating

fuse designs to pinpoint the blown fuse and

eliminate the troubleshooting danger.

Older industrial facilities might even have

older electromechanical relays that require

maintenance personnel to periodically

remove or enter the cabinet to maintain

and calibrate them. Newer microprocessor-

based relays offer more precise measure-

ment, protection features and communica-

tion abilities which improve safety.

High-resistance grounding systems eliminate

arc flash on the first ground fault. For any

facility an excellent way to reduce arc-flash

hazard and prevent unnecessary downtime

is to install a high-resistance grounding

(HRG) system. The majority (95%) of elec-

trical faults begin as ground faults, and so

improving the safety of the electrical system

when a ground fault occurs has a significant

Table 1 . Risk hierarchy and components to design in safety

Risk Hierarchy Safety Control Point Benefit Design In Component(s)

Engineering controls Reduce risk of electrical shock Industrial GFCIs

Limit arc-flash incident energy levels

Arc-flash relaysCurrent-limiting fuses

Substitution Update older equipment Current-limiting fusesReplace renewable fusesIndicating fusesElectromechanical relays

Update grounding method High-resistance groundingNGR monitoring

Elimination Remote diagnostics to avoid electrical exposure

Bluetooth-enabled overload relays



effect on the overall system safety.

In a resistance-grounded system, the neu-

tral point is connected to ground through

a neutral-grounding resistor (NGR) used to

limit current. The NGR resistance is small

enough to provide the stability of a solidly

grounded system and large enough to limit

ground-fault current. Since the NGR limits

current available to the fault, point-of-fault

damage is minimized, ground-fault voltage

is controlled, and the risk of an arc flash

caused by a ground fault is eliminated.

An HRG system may remain online when a

ground fault occurs and the easiest way to

detect when it occurred is by using a cur-

rent-sensing ground-fault relay. It’s impor-

tant that the ground-fault relay used on an

HRG system is sensitive enough to detect

faults as low as 10% of the NGR let-through

fault current. The main disadvantage of

resistance grounding is that the resistor

can fail over time so continuous monitor-

ing of the neutral-to-ground path to verify

that the neutral-grounding resistor (NGR) is

intact is critical.

RISK HIERARCHY: ELIMINATION .The Industrial Internet of Things (IIoT)

holds promise for electrical safety, espe-

cially as a tool to use remote diagnostics to

avoid opening panels. As experienced work-

ers retire, younger workers who replace

them have less skill with hand tools and

wires, and less familiarity with safe work

practices. If electrical equipment can com-

municate its status to workers via the IIoT

or wirelessly, then there will be less need

for workers to enter electrical panels and be

exposed to arc flash and shock hazards.

SUMMARYThe Hierarchy of Controls is a useful guide

as to where components can be integrated

and be used to control, substitute, and

even eliminate electrical risk in a facility.

Upgrading current-limiting fuses and using

arc-flash relays, industrial GFCI, and Blue-

tooth® enabled relays to design in safety

need not be expensive and the return on

safety investment is well worth it. Workers

and business owners need to be reminded

that while PPE is essential and is the last

line of defense in an electrical hazard. The

best way to reduce risk of injury from elec-

trical hazards is to design in safety from

the start.

Dean Katsiris is product manager for

protection relays in the industrial business

unit at Littelfuse, Inc. (www.littelfuse.com).

Dean holds bachelors’ degrees in Electrical Engineering

and Computer Science from the University of Saskatch-

ewan, and is an IEEE member.

Dave Scheuerman is technical training

manager in the industrial business unit at

Littelfuse, Inc. Dave holds a Bachelor of

Science in Electrical Engineering from Purdue University

and is a member of IEEE, NFPA, and IAEI.

http://www.littelfuse.com

schneider-electric.us/engineeringservices

Do you comply with NFPA 70E 2018?

Get the facts on new policies and requirements.

NFPA 70E-2018 implements many new policies and requirements that impact how companies manage the safety of their workers, assess the hazards of electrical systems and mitigate the arc flash hazard to an acceptable level.

Learn how NFPA 70E-2018 might impact your company's power systems by watching our webinar, “Key Updates to NFPA 70E - 2018”.

https://go.schneider-electric.com/NAM_FS_US_201803_Consulting-Services-NFPA70E-2018-Webinar-ESSR_01-Key-Updates-to-NFPA-70E-2018-Webinar-LP.html



Exposure to electricity resulted in 154 workplace fatalities and 1,850 cases with

days away from work in 2014, according to the 2017 edition of the National Safety

Council’s “Injury Facts” data. Industry consensus standards like The National Fire

Protection Agency’s (NFPA) article 70E, Standard for Electrical Safety in the Workplace,

are designed to provide safe work practices and protect personnel by reducing risk when

exposed to electrical hazards.

NFPA 70E requirements are updated every three years. Here’s a look at what you need to

know about this year’s revision.

• Job safety planning: Previously, a simple job safety briefing sufficed. Now, a written

safety plan must be made for all electrical work where employees are exposed to elec-

trical hazards. The condition and maintenance of equipment now must also be account-

ed for in the plan.

• Equipment labeling: The new exception to 130.5(H) allows for possible alternatives to tra-

ditional labeling of equipment providing the option for a digital smart label in the form of

a barcode or QR code. These labels can link to a central database and give workers easier

access to the same necessary hazard information, such as voltage and current and energy

levels normally printed directly on the equipment.

NFPA 70E 2018: What you need to know to protect yourselfIn 2014, exposure to electricity resulted in 154 workplace fatalities and 1,850 cases with days away from work in 2014

By Corey Jasper, Schneider Electric



• Risk assessment procedure: One of the

more significant updates, the risk assess-

ment procedure now specifically requires

electrical workers to address human error

and its negative consequences on peo-

ple, processes, work environments and

equipment.

Organizations are required to incorporate

an hierarchy of control methods (in order

of priority) to more effectively reduce risk

to an acceptable level. This revision takes

into consideration that personal protective

equipment (PPE) should be considered only

as the last line of defense for protecting

against injury — not preventing an incident

from happening.

Arc flash risk assessment: This section has

been revised and moved, and is now Table

130.5(C). The table can be used for both

ways of doing an arc flash risk assessment,

as it now also applies to the incident energy

analysis. The assessment protocol is:

1. identify arc flash hazards;

2. estimate the likelihood of occurrence

of injury or damage to health and the

potential severity of injury or damage to

health; and,

3. determine if additional protective mea-

sures are required.

PPE selection . Formerly part of the Annex

material, this table [now Table 130.5(G)] has

moved into the standard’s mandatory text.

The table provides guidance on the selec-

tion of PPE based on the calculated level

of incident energy. Based on how the table

has separated the different incident energy

levels, it leads the user to a more simplified

approach to selecting PPE (i.e., using a 2

level simplified approach rather than have 4

or 5 categories to choose from).

CREATING A CULTURE OF SAFETYWhile the NFPA 70E guidelines provide a

comprehensive framework, it’s important to

remember that there’s no cookie cutter rec-

ipe for managing electrical safety. It largely

depends on the facility and the industry

in which your business operates. Here are

some best practices to consider:

• Perform preventative maintenance . Don’t

be a run to fail facility that can never shut

down operations and do maintenance.

The longer you go without maintenance

the more risk you put into the system. By

regularly monitoring and testing all the

critical elements of your electrical distri-

bution system (transformers, breakers,

generators, etc.) you can start to develop

trend lines around the life expectancy of a

specific piece of equipment so it’s less of

a guessing game.



• De-energize equipment . Mitigate any

potential risks by removing the hazard

entirely. With de-energized equipment

there is no arc flash hazard, no chance

of damaging equipment and no shock or

electrocution danger. This might be more

of a challenge for mission critical facili-

ties like hospitals or an older facility that

doesn’t have the necessary redundancy.

Each facility must establish their accept-

able level of risk.

• Sectionalize equipment . Instead of having

a large, open control panel you can sec-

tionalize off the different voltage levels.

This way workers don’t have to shut down

the entire panel because they’ve effec-

tively protected themselves from being

exposed to or shocked by higher voltages.

As NFPA 70E notes, electrical safety is a

shared responsibility between employers

and employees and requires a collaborative

effort to keep everyone safe.

Corey Jasper is a principal power system

engineer for Schneider Electric (www.

schneider-electric.com) based in St. Louis,

MO, where he has worked for more than 10 years. Corey

has experience with review and development of electrical

safe work practices policies, as required by NFPA 70E.

Contact him at [email protected].



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Hand-held airborne and structure-borne ultrasound instruments sense and receive

high frequency sound waves that are produced from various sources that include

turbulence such as a compressed air leak, friction as in an under lubricated bearing,

and ionization in electrical discharges. These high frequency sounds are above the range of

normal human hearing, and therefore cannot be heard in the audible range. The instrument

receives the high frequency sound, and through a process called heterodyning, translates the

high frequency sound into an audible sound heard through the headset by the inspector. The

sound is then measured as a decibel (dB) on the display panel of the instrument.

Ultrasound is probably the most versatile of any predictive maintenance (PdM) technol-

ogy. Typical applications for ultrasound include compressed air and gas leak detection,

bearings, motors, gearboxes, valves, steam traps, hydraulic applications, and for condition

based lubrication of bearings and rotating equipment.

When it comes to electrical inspection, ultrasound instrumentation can be used on al-

most any energized electrical equipment including metal-clad switchgear, transformers,

substations, relays, and motor control centers just to name a few. Ultrasound instruments

can be used to inspect energized electrical components that are on low, medium, and

high voltage systems.

Electrical equipment reliability with ultrasound and infraredFor inspection of energized electrical equipment, ultrasound instruments are joining the electrical inspector’s toolbox alongside noncontact infrared cameras

By Adrian Messer, UE Systems, Inc.



ULTRASOUND AND IRTraditional inspection of

energized electrical equip-

ment has been performed

by noncontact infrared

cameras. However, in recent

years, ultrasound instru-

ments have been added

to these inspections for

various reasons. One of

the main reasons has been

safety. An ultrasound in-

spection of electrical equip-

ment can be performed

without opening the cabinet

or enclosure.

One electrical anomaly that

ultrasound will detect is

corona (see Figures 1 and

2). Even though corona

produces little to no heat,

it does produce ultrasonic

emissions. If the inspector’s

ultrasound instrument has

on-board sound recording

capability, the ultrasound

emission from corona can be

recorded and further ana-

lyzed for a correct diagnosis.

A note of importance on

corona is the fact that it

is only present in voltage

above 1000 volts. At 1000

volts and greater, air be-

Figures 1 and 2 . Picture view and infrared view of obvious signs of destructive corona . Corona typically does not show a significant delta-T with infrared . (Photos courtesy of Jim Brady)

Figure 3 . Recorded ultrasound of corona as seen in an FFT spectral view



comes a conductor and

hence the ionization of air

surrounding a connection

can occur. If inspection is

being done on voltages

below 1000 volts, and an

ultrasound is heard, the in-

spector can rule out corona

as a possible diagnosis.

When the recorded ultra-

sound of corona is looked at

in a spectrum analysis soft-

ware (see Figure 3), very

prominent 60Hz harmonics

can be noted. If the sound

recording is done outside of

North America, one would

see very dominant 50Hz

harmonics. Additionally, in

between the 60Hz harmon-

ics, you would see what is

referred to as frequency

content. Frequency con-

tent is basically harmonic

activity between the more

dominant harmonics. As the

condition worsens, there

will be a loss of the domi-

nant 60Hz harmonics, and

uniformity in the amplitude

of the recorded ultrasound

will decrease.

Tracking (see Figure 4)

occurs when there is a low

current pathway to ground

across an insulator. Many

will refer to tracking as

“baby-arcing.” This event

is common where there is

severe breakdown of the in-

sulating material and loose

connections. Tracking can

occur in low, mid, and high

voltages and characterized

as a steady buzzing sound

with periodic “crackling”

and “popping” sounds. Fur-

ther damage is done when

tracking is not corrected,

and will rather quickly lead

to arcing.

The move from corona to

tracking leads to a destruc-

tive path across the insula-

tion, and creates pin-holes

and spider web like tracking

which causes surface dete-

rioration. When visually in-

spected, one can see a very

obvious tracking path on the

surrounding surfaces. Also, a

conductive cloud of ionized

air surrounds the connec-

tions. Flash-over can now

occur once a tracking path

is complete from phase to

phase, or phase to ground.

Finally, arcing happens

when there is a discharge

to ground across an insula-

tor. Arcing causes severe

damage to equipment,

plant/facility operations,

and people. Melting of con-

nectors, damage or loss of

insulation, and fires usually

result from electrical arcs.

Arcing can easily be heard

and detected with ultra-

sound (see Figure 5). The

Figure 4 . Tracking as seen in the time series view



sound characteristic for arc-

ing is a rather erratic bursts

of discharges and popping

sounds. These are identifi-

able when looking at a re-

corded ultrasound of arcing

in the Time Wave Form.

EXAMPLE 1: 2000 AMP MAIN BREAKER Figure 6 shows a 2000

Amp main breaker. Arc-

ing was detected on the B

Phase line side. The arcing

heard was worse when the

load increased. The arcing

has severely deteriorated

the internal contacts, and

eventually will become do

deteriorated that the volt-

age and wave form will be

unable to reach the load.

At this particular facility,

the replacement cost for

this item is approximately

$20,000 USD.

EXAMPLE 2: 2000 KVA TRANSFORMERThe next example is from a

2000 KVA 11KV-415v cast

resin transformer (see Fig-

ures 7 and 8). An inspection

on this equipment was re-

quested after audible noise

in the area increased, so the

operators knew something

has changed for the area to

become louder. The inspec-

tion was done during the

winter months, and for this

facility, this transformer typi-

Figure 5 . Arcing as seen in the Time Wave Form . Notice the lack of uniform harmonics and the sudden starts and stops of the discharge .

Figure 6 . Images of the 2000 amp main breaker



cally sees a reduction in load

as it supplies chillers and as-

sociated other plant equip-

ment that normally does

not work as hard during the

winter months. During the

inspection it was noted that

the load was around 420

Amps per phase.

EXAMPLE 3: ORBIT MOTORThe next example is from

a contactor on a piece of

equipment called an orbit

motor. A routine airborne

ultrasound inspection was

done, and distinct sounds

of tracking were heard (see

Figures 9 and 10). A follow

up inspection with infra-

red was performed, and

the diagnosis was severe

tracking.

CONCLUSIONUltrasound instruments are

versatile and easy to use,

and can greatly enhance

inspections on almost any

electrical equipment. In the

end, it’s all about safety.

Ultrasound inspections can

be done prior to opening

the energized gear to scan

with infrared. If an ultrason-

ic emission is heard, then

the proper precautions can

be taken before opening

the energized cabinet. Also,

for those that rely on the

services of an outside con-

tractor to perform infrared

scans, an ultrasound scan

can be done in between the

annual infrared scan to see

if any emissions are heard.

When ultrasound and infra-

red are used together, an

inspector is given a greater

chance of detecting anoma-

lies that could potentially be

Figure 8a . Time Wave Form view of recorded ultrasound from this transformer showing charac-teristics of arcing

Figure 8b . Time Wave Form view of another 2000KVA transformer in the same facility showing normal ultrasonic noise for this type of transformer

Figure 7 . Picture view and infrared view of the 2000KVA transformer .



missed when relying on just one single tech-

nology. For best results, analyzing recorded

ultrasounds in either the FFT, or time wave

form view is the recommended method of

diagnosing electrical anomalies heard with

ultrasound.

Adrian Messer, CMRP, is manager of U.S.

operations at UE Systems (www.uesys-

tems.com). Contact him at adrianm@

uesystems.com.

Figure 9 . Picture view and infrared view of the Orbit Motor

Figure 10 . Time Wave Form view of the recorded ultrasound of this contactor show distinct signs of severe tracking and early stages of arcing .



mailto:adrianm%40uesystems.com?subject=

mailto:adrianm%40uesystems.com?subject=



ADDITIONAL RESOURCESAVO Electrical Technician Certification Programs

An AVO Training Electrical Technician Certification offers many

benefits. Not only do our 12 Certifications help improve technical

knowledge and job skills, they also enable career opportunities

and the ability for companies to be more successful when bidding

projects. The hands-on training portion of our Technician Certifi-

cation assist employers in qualifying their technicians. Qualified

Persons, by definition, are required to “demonstrate skills and

knowledge related to the construction and operation of electrical

equipment and installations.” In addition, all AVO Electrical Certi-

fications help meet the retraining requirements of NFPA 70E-2018

paragraph 110.2(A)(3).

Reliable protection of electronics in ordinary or hazardous

locations

There is no dispute that power densities have increased as en-

closure volumes have gotten smaller. Packing components more

densely reduces the circuit size and increases speed but leaves little

room for heat dissipation. Tightly packed enclosures and panels

restrict airflow, resulting in rapidly rising internal temperatures,

thermal runaway and increasing control failures. Vortex cooling

offers safe and reliable alternatives to the problems with conven-

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ant based air conditioning. Learn how Vortec Enclosure Coolers can

provide reliable protection of your control panels and other sensi-

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ADDITIONAL RESOURCESOn-line Demo: Test Drive the New Bluetooth® Overload Relay

The smart Littelfuse® MP8000 Bluetooth Enabled Overload relay

is a universal relay that can communicate directly with your smart-

phone via Bluetooth. No need to open the control panel. Moni-

tor and control unlimited relays through the Littelfuse App on the

smartphone you already own from a safe distance. The universal

relay works on all single or 3-phase motors and pumps with operat-

ing voltages of 90-690 VAC.

See the on-line demo:

www.littelfuse.com/products/landing-pages/electrical/demos/

“NFPA 70E Changes: Now Everyone Can Benefit from the Tables”

by Rod West

The 2018 edition of NFPA 70E included several updates, including

job safety planning, risk controls, risk assessments and changes

to the tables. Read our blog “NFPA 70E Changes: Now Everyone

Can Benefit from the Tables” to gain further insight into the table

changes.

https://blog .schneider-electric .com/energy-regula-

tions/2017/07/12/nfpa-70e-changes-now-everyone-can-benefit-

tables


https://go.schneider-electric.com/NAM_FS_US_201803_Consulting-Services-NFPA70E-2018-Webinar-ESSR_01-Key-Updates-to-NFPA-70E-2018-Webinar-LP.html

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ADDITIONAL RESOURCES

UE Systems 4Cast

The UE Systems 4Cast is a smart alert system that records data

and sounds continuous-

ly, issues alarms, sends

data and sound samples

to DMS software for

analysis and report-

ing. Data along with

sound samples can be

reviewed and analyzed to determine the condition of a bearing just

before, during and after a change in alarm status. This provides

important information to help understand what happened and

when it happened. Permanently installed transducers continuously

monitor bearing condition 24 hours a day, 7 days a week. All data

is stored locally. Should a change in condition occur and a pre-es-

tablished alarm level is entered, the system, via the plant’s Ethernet

will issue an alarm notification, enter data and sound samples into

DMS software until the alarm condition has been reversed. Learn

more by viewing this webinar.

http://www .uesystems .com/training/introduction-ue-systems-

4cast






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