Issue: 1016th September 2015

BA427Eintrinsically safe2-wire 4/20mA

manual set pointstation.

For instruments with firmware 1.04and later. Issued June 2015.

Issue 10

1. Description

2. Operation2.1 Controls – two handed2.2 Controls – one handed2.3 Displays

3. Intrinsic Safety Certification3.1 ATEX gas certification3.2 Zones, gas groups & T rating3.3 Special conditions for safe use3.4 4/20mA output3.5 Certification label information

4. System Design for Hazardous Areas 4.1 4/20mA loop using Zener barriers4.2 4/20mA loop using Galvanic

Isolators.

5. Installation5.1 Location5.2 EMC5.3 Installation procedure5.4 Scale card

6. Configuration and Calibration 6.1 Summary of configuration functions6.2 Adjustment resolution6.3 Position of decimal point6.4 Calibration of display using external

meter.6.5 Calibration of display using internal

reference.6.6 High & low current output limits6.7 Pre-set outputs6.8 Maximum output rate of change6.9 Function of P push button in operating

mode.6.10 Encoder6.11 One or two handed operation6.12 Security code6.13 Reset to factory defaults

7. Maintenance 7.1 Fault finding during commissioning7.2 Fault finding after commissioning7.3 Servicing7.4 Routine maintenance7.5 Guarantee7.6 Customer comments

8. Accessories 8.1 Scale card8.2 Tag information8.3 Display backlight

8.3.1 Loop powering the backlight8.3.2 Separately powering the

backlight.8.4 Rotary encoder

Appendix 1 Dust certification

Appendix 2 IECEx certification

Appendix 3 ETL / cETL certification

The BA427E is CE marked to show compliance with the European Explosive Atmospheres Directive 94/9/EC

and the European EMC Directive 2004/108/EC

CONTENTS

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1. DESCRIPTIONThe BA427E is an intrinsically safe, loop powered,panel mounting Set Point Station which enables thecurrent flowing in a 4/20mA loop to be manuallyadjusted from within a hazardous process area viathe front panel push buttons, or an optional externalrotary control. The BA427E output is adjustablebetween 3 and 22mA but the output range may berestricted if only limited adjustment is required. Inaddition to the output being continuously variable,five pre-set output currents may be configured andsubsequently selected from the front panel pushbuttons. To minimise plant disturbance themaximum output rate of change may be defined.

Adjustment of a plant parameters represented by a4/20mA current is the main application for BA427ESet Point Stations. A controller set point, actuatorposition or any 4/20mA variable may be manuallyadjusted.

The BA427E incorporates a 5 digit display and a 31segment bargraph which may be calibrated todisplay the 4/20mA output current in any linearengineering units. An optional factory fittedbacklight, which may be loop or separately powered,enables this display to be read in all lightingconditions.

All BA427E Set Point Stations and the optionalbacklight have been certified intrinsically safe for usein gas and dust hazardous areas by Notified BodyIntertek Testing and Certification Ltd. Thiscertification has been used to confirm compliancewith the European ATEX Directive 94/9/EC.

For international applications the BA427E has IECExcertification which is described in Appendix 2.

For use in the USA and Canada the BA427E carriesthe ETL/cETL Mark, this certification is described inAppendix 3.

2. OPERATIONThis instruction manual describes ATEX systemdesign and installation for use of the BA427E in agas hazardous area. Please refer to Appendix 1 fordetails of ATEX dust certification and to Appendix 2for IECEx certiification.

Fig 1 shows a simplified block diagram of theBA427E manual Set Point Station. The 4/20mAcurrent flowing in the loop may be manually set atany value between approximately 3 and 22mA usingthe front and panel push buttons. Initially theoutput current changes slowly, but after the buttonhas been pressed for five seconds the rate ofchange accelerates to allow large changes to bemade quickly.

The five pre-set outputs, which are selectable via theinstruments front panel push buttons, allow theoperator to quickly select frequently used plant setpoints.

To prevent plant disturbance the maximum rate ofoutput current change initiated by operating the frontpanel push buttons, switching between pre-setoutputs or using an optional external encoder maybe defined.

The output resistance of the BA427E is very high,within the specified operating voltage range, the loopcurrent will therefore be unaffected by changes in thesupply voltage.

CautionThe BA427E output should not be used for

critical safety applications.

Versatile calibration facilities allow the 5 digit internaldisplay to show the 4/20mA output current in linearengineering units. For example, in an applicationwhere the BA427E is being used to adjust the setpoint of a speed controller, the internal indicator maybe calibrated to display the required speed in RPM.

For applications in poorly illuminated areas a factoryfitted green backlight is available which may be loopor separately powered. When loop powered thebacklight produces background illumination enablingthe display to be read at night or in poor lightingconditions. No additional power supply, intrinsicsafety interface or field wiring are required, but theSet Point Station voltage drop is increased. Whenseparately powered, the backlight is brighter but anadditional intrinsic safety interface and field wiringare required.

Fig 1 Simplified block diagram of BA427E

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2.1 Controls - two handedThe BA427E Set Point Station is controlled andconfigured via four front panel push buttons locatedbelow the display. In the operating mode i.e. whenthe Set Point Station is controlling the loop currentand the display is showing the output in engineeringunits, these push buttons can have two alternativesets of functions depending upon if the Set PointStation has been configured for two or single handedoperation..

Two handed operation is the default configurationwhich minimises the possibility of accidentaladjustment. of the output current by requiring that theE button be pressed at the same time as the ▼ or ▲button to make an adjustment. :This configurationalso prevents the optional external encoder fromadjusting the output current unless the E button isoperated.

E + ▼ Output current slowly decreases. After fiveseconds the rate of change accelerates sothat large changes may be made quickly. .

E + ▲ Output current slowly increases. After fiveseconds the rate of change accelerates sothat large changes may be made quickly.

E Continuously pushing this button for 5seconds allows the Set Point Station outputto be entered in engineering units digit bydigit using the ▲ or ▼ push button toadjust the flashing digit and the P button tomove control to the next digit. When setas required, pressing the E button will enterthe new set point.

P While this button is pushed the BA427ESet Point Station will display one of threealternatives depending upon how theinstrument has been configured:

Output current mA without bargraph

Output as a % of span

Pre-set outputs in engineering unitsThe display will flash. While continuing topress the P button, operating the ▼ or ▲button will show the identification of thepre-set closest to the present Set PointStation output, followed by the pre-setvalue. Operating the ▼ or ▲ button willscroll through the five pre-sets and an‘Abort’ position.Releasing both buttons will leave theselected pre-set value or ‘Abort’ legendflashing for ten seconds, during which timeoperating the E button will update the SetPoint Station output to the displayed pre-set value. If the E button is not operatedduring this period, the Set Point Stationoutput will not be changed and the originalengineering display will be shown.

▼ While this button is pushed the Set PointStation will display the numerical value andanalogue bargraph the Set Point Stationhas been calibrated to display with a 4mA*output. When released the normal displayin engineering units will return.

▲ While this button is pushed the Set PointStation will display the numerical value andanalogue bargraph the Set Point Stationhas been calibrated to display with a20mA* input. When released the normaldisplay in engineering units will return.

* If the Set Point Station display has beencalibrated using the CAL function,calibration points may not be at 4 and20mA.

P + ▼ Firmware number followed by version.This manual applies to firmware version1.04 and above.

P + E Access to configuration menu via optionalsecurity code.

2.2 Controls - single handedThe BA427E Set Point Station is controlled andconfigured via four front panel push buttons locatedbelow the display. In the operating mode i.e. whenthe Set Point Station is controlling the loop currentand the display is showing the output in engineeringunits, these push buttons can have two alternativesets of functions depending upon if the Set PointStation has been configured.

For single handed operation only the ▲ or ▼ pushbutton has to be pressed to adjust the output currentas shown below. This configuration also allows theoptional external encoder to adjust the output currentwithout the E button being operated.:

▼ Output current slowly decreases. After fiveseconds the rate of change accelerates sothat large changes may be made quickly.

▲ Output current slowly increases. After fiveseconds the rate of change accelerates sothat large changes may be made quickly.

E Continuously pushing this button for 5seconds allows the Set Point Stationoutput to be entered in engineering unitsdigit by digit using the ▲ or ▼ push buttonto adjust the flashing digit and the P buttonto move control to the next digit. Whenset as required, pressing the E button willenter the new set point.

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P While this button is pushed the BA427ESet Point Station will display one of threealternatives depending upon how theinstrument has been configured:Output current mA without bargraph

Output as a % of span

Pre-set outputs in engineering unitsThe display will flash. While continuing topress the P button, operating the ▼ or ▲button will show the identification of thepre-set closest to the present Set PointStation output, followed by the pre-setvalue. Operating the ▼ or ▲ button willscroll through the five pre-sets and an‘Abort’ position.Releasing both buttons will leave theselected pre-set value or ‘Abort’ legendflashing for ten seconds, during which timeoperating the E button will update the SetPoint Station output to the displayed pre-set value. If the E button is not operatedduring this period, the Set Point Stationoutput will not be changed and the originalengineering display will be shown.

P + ▼ Firmware number followed by version.This manual applies to firmware version1.04 and above.

P + E Access to configuration menu via optionalsecurity code.

2.2 DisplaysThe BA427E Set Point Station has a 5 digit displayplus a 31 segment bargraph.

The digital display may be calibrated using the ‘CAL’or ‘5Et’ functions to display the engineering variablerepresented by the Set Point Station’s 4/20mAoutput, such as temperature, pressure or speed.

The digital display shows the requested Set PointStation output in engineering units, the digital displaywill flash until the Set Point Station output is thesame as the requested output.

The bargraph, which is not adjustable, always showsthe actual Set Point Station output. The bargraphstarts and finishes at the two currents at which thedigital display was calibrated, usually 4 and 20mA.See sections 6.4 and 6.5.

3. INTRINSIC SAFETY CERTIFICATIONAll BA427E Set Point Stations have ATEX andIECEx gas and dust intrinsic safety certification.This section of the instruction manual describesATEX gas certification. ATEX dust and IECExapprovals are described in Appendixes 1 and 2.

3.1 ATEX gas certificationNotified Body Intertek Testing and Certification Ltdhave issued the BA427E Set Point Station with anEC-Type Examination Certificate numberITS12ATEX27718X. This confirms compliance withharmonised European standards and it has beenused to confirm compliance with the European ATEXDirective for Group II, Category 1G equipment,Ex ia IIC T5 Ga Ta = -40 to +70ºC. The Set PointStation carries the community mark and subject tolocal codes of practice may be installed in any of theEuropean Economic Area (EEA) member countries.ATEX certificates are also acceptable forinstallations in Switzerland.

This section of the instruction manual describesATEX installations in explosive gas atmospheresconforming with EN60079-14 Electrical Installationsdesign, selection and erection. When designingsystems for installation outside the UK the localCode of Practice should be consulted.

3.2 Zones, gas groups and T ratingThe BA427E Set Point Station has been certifiedEx ia IIC T5 Ga. When connected to a suitablesystem the Set Point Station may be installed in:

Zone 0 explosive gas air mixturecontinuously present.

Zone 1 explosive gas air mixture likelyto occur in normal operation.

Zone 2 explosive gas air mixture notlikely to occur, and if it does will only exist for a short time.

Be used with gases in groups:Group A propaneGroup B ethyleneGroup C hydrogen

Having a temperature classification of:T1 450oCT2 300oCT3 200oCT4 135oCT5 100oC

At ambient temperatures between -40 and +70oC.

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This allows the BA427E Set Point Station to beinstalled in all gas Zones and to be used with mostcommon industrial gases except carbon disulphideand ethyl nitrite which have an ignition temperatureof 95ºC.

3.3 Special conditions for safe useThe BA427E ATEX certificate has an ‘X’ suffixindicating that special conditions apply forinstallations in IIIC conductive dust atmospheres.No special conditions apply for installations in gas orin IIIA and IIIB dust atmospheres. See Appendix 1for information about use in dust atmospheres.

3.4 4/20mA output Input safety parameters for the 4/20mA output,terminals 1 and 3 are:

Ui = 30V dcIi = 200mAPi = 0.84W

Equivalent maximum capacitance and inductancebetween the two 4/20mA output terminals 1 and 3 is:

Ci = 2.2nFLi = 0.01mH (8µH)

Maximum permitted loop cable parameters can becalculated by adding these figures to Ci and Li ofother instruments in the loop and subtracting thetotals from the maximum cable capacitance Co andcable inductance Lo permitted for the Zener barrier,galvanic isolator or associated apparatus poweringthe loop.

3.5 Certification label informationThe certification information label is fitted in a recesson the top outer surface of the instrument enclosure.It shows the ATEX, IECEx and ETL certificationinformation, instrument serial number, year ofmanufacture plus BEKA associates name andlocation.

BA427E certification label

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4. SYSTEM DESIGN FOR HAZARDOUS AREAS

4.1 4/20mA loop using Zener barriersFig 2 illustrates a typical application in which aBA427E Set Point Station mounted in a hazardousarea is being used to adjust the setpoint of a speedcontroller located in a safe area. To enable thenegative side of both the speed controller and thepower supply to be connected together and earthed,a Zener barrier is required in series with both theoutgoing and return wires connected to the BA427ESet Point Station.

The Zener barrier(s) should be ATEX certified withcombined output parameters equal to or less thanthe maximum BA427E input safety parameters.Most Zener barriers are certified Ex ia IIC allowingthem to be connected to equipment located in anyZone and to be used with any gas group thussimplifying selection.

For this application a wide range of devices may beused. A 28V; 93mA positive polarity device in theoutgoing wire and a diode return barrier in the returnwire are industry standard devices which areavailable from most barrier manufactures oftenhoused in a single package.

The maximum permitted cable parameters are thosespecified by the Zener barrier certificate, less thesum of equivalent input capacitance and inductanceCi & Li of all the other instruments in the loop, in thisexample just the BA427E.

When designing the loop it is necessary to establishthat the maximum voltage drop caused by the SetPoint Station, both Zener barrier channels, the load(speed controller input) and the cable resistance isalways less than the minimum power supply voltage.

Fig 2 Typical application using barriers

In this example:

Minimum operating voltage of BA427E 6.1V

Maximum voltage drop caused by 28V 6.8V93mA Zener barrier(340 end-to- end resistance x 20mA)

Maximum voltage drop caused by 1.3Vdiode return barrier

Maximum voltage drop caused by 5.0Vspeed controller input.(250 x 20mA)

Maximum voltage drop caused by 0.2Vcable resistance(10 x 20mA)

______Total maximum voltage drop 19.4V

The minimum power supply voltage must thereforebe above 19.4V, but below 25.5V which is themaximum working voltage of a typical 28V Zenerbarrier.

If the BA427E Set Point Station includes an optionalbacklight which is loop powered, the minimumoperating voltage of the instrument increases from6.1 to 10V. See section 8.3.1

4.2 4/20mA loop using Galvanic IsolatorsGalvanic isolators, although more expensive thanZener barriers, do not require a high integrity earthconnection. For small systems where a high integrityearth is not already available, the use of galvanicisolators often reduces the overall installation cost.

The example described in section 4.1 can besimplified by the use of a galvanic isolator as shownin Fig 3.

Fig 3 Typical application using a galvanic isolator

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Any 4/20mA ATEX certified 4/20mA galvanic isolatorwith output safety parameters equal to or less thanthe maximum BA427E certified input parametersmay be used.

The maximum permitted cable parameters are thosespecified on the galvanic isolator certificate, less thesum of equivalent input capacitance and inductanceCi & Li of all the other instruments in the loop, in thisexample just the BA427E.

When designing the loop it is necessary to ensurethat the supply voltage between terminals 1 & 3 ofthe BA427E Set Point Station always exceeds 6.1Vwhich is the minimum operating voltage. If the BA427E Set Point Station includes an optionalbacklight which is loop powered, the minimumoperating voltage of the instrument increases from6.1 to 10V. See section 8.3.1

5. INSTALLATION

5.1 LocationThe BA427E Set Point Station has a robust glassreinforced modified PPO enclosure with a toughenedglass window. The front of the instrument has IP66protection and a gasket seals the joint between theSet Point Station enclosure and the panel. The rearof the instrument has IP20 protection.

Installation may therefore be in any panel providingthat the operating temperature is between –40ºC and+70ºC and intrinsic safety requirements are satisfied.

Fig 4 shows the overall dimensions of the BA427Etogether with the recommended panel cut-outdimensions and terminal identifications. To achievean IP66 seal between the instrument enclosure andthe instrument panel an aperture with therecommended tolerance should be used.

The BA427E certification label carries a warning:

‘Potential electrostatic charging hazard clean only with a damp cloth’

Care should be taken when cleaning the front of theinstrument, although the warning only applies to thecase as the glass window and keypad will notsupport a static charge.

Cut-out dimensionsRecommended for all installations.

Mandatory to achieve an IP66 seal between theBA427E Set Point Station and the instrument panel

90 +0.5/-0.0 x 43.5 +0.5/-0.0mm

Fig 4 BA427E dimensions

CautionAlthough the front of the Set Point

Station has IP66 protection, it should beshielded from direct sunlight and severe

weather conditions.

5.2 EMC BA427E Set Point Stations comply with therequirements of the European EMC Directive2004/108/EC. For specified immunity all wiringshould be in screened twisted pairs, with the cablescreen earthed at one point within the safe area.

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5.3 Installation Procedure

a. Cut the specified aperture in the panel. Toachieve an IP66 seal between the instrumentenclosure and the instrument panel theaperture must have the dimensions specifiedin Fig 4.

b. Slide the gasket over the body of the Set PointStation before inserting the instrument into thepanel aperture.

c. Firstly ensure that both the panel mountingclamps are closed by turning the knurledscrews fully anti clockwise until the two pips inthe clamp foot align with holes in the clampbody.

d. Place a clamp in the recess on each side ofthe Set Point Station, pulling gently to slide itonto the dovetail as shown in Fig 5. Push theknurled screw slightly forward to engage thethread and tighten by turning clockwise until itis just finger tight. When both clamps are fittedensure that the gasket behind the front panelbezel is correctly positioned before fullytightening the clamps to secure the instrument.The maximum recommended clamp tighteningtorque is 22cNm (1.95 lbf in) which isapproximately equivalent to finger-tight plusone half turn. Do not over tighten.

e. Connect the panel wiring to the rear terminalblock(s) as shown in Fig 4. To simplifyinstallation, the terminals are removable so thatthe panel wiring can be completed before theinstrument is installed. Wiring should besecured to prevent vibration damage.

Fig 5 Fitting panel mounting clamps

5.4 Scale cardThe engineering units of measurement represent bythe Set Point Station’s 4/20mA output current maybe shown on a printed scale card in a window at theright hand side of the display. The scale card ismounted on a flexible strip that is inserted into a slotat the rear of the instrument as shown in Fig 6. Thusthe scale card can easily be changed withoutremoving the Set Point Station from the panel oropening the instrument enclosure.

New instruments are supplied with a printed scalecard showing the requested units of measurement, ifthis information is not supplied when the instrumentis ordered a blank card will be fitted.

A pack of self-adhesive scale cards printed withcommon units of measurement is available as anaccessory from BEKA associates. Custom printedscale cards can also be supplied.

To change a scale card, unclip the end of the flexiblestrip that is accessible from the rear of theinstrument by gently pushing the strip upwards andpulling it out of the enclosure. Peel the existing scalecard from the flexible strip and replace it with a newprinted card, which should be aligned as shown inFig 6. Do not fit a new scale card on top of anexisting card.

Install the new scale card by gently pushing theflexible strip into the slot at the rear of the Set PointStation, when it reaches the internal end-stop secureit by pushing the end of the flexible strip downwardsso that the tapered section is held by the rear panel.

Align the self-adhesive printedscale card onto the flexible stripand insert the strip into the SetPoint Station as shown below.

Fig 6 Inserting flexible strip carrying scale cardinto slot at the rear of Set Point Station.

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6. CONFIGURATION AND CALIBRATIONSet Point Stations are configured and calibrated viathe four front panel push buttons. All theconfiguration functions are contained in an easy touse intuitive menu that is shown diagrammaticallyin Fig 7.

Each menu function is summarised in section 6.1and includes a reference to more detailedinformation.

Throughout this manual push buttons are shown asP, E, ▼ or ▲ and the Set Point Station displaylegends are shown within inverted commas e.g.'CAL' and 'CodE'.

Access to the configuration menu is obtained byoperating the P and E push buttons simultaneously.If the Set Point Station security code is set to thedefault 0000 the first parameter 'rE5n' will bedisplayed. If a security code other than the defaultcode 0000 has already been entered, the Set PointStation will display 'CodE'. Pressing the P buttonwill result in ‘0000’ being displayed with one digitflashing. To gain access the four digit security codeshould be entered using the ▲ and ▼ push buttonsto set the flashing digit and the P button to movecontrol to the next digit. When the correct four digitcode has been entered, pressing E will cause thefirst parameter 'rE5n' to be displayed. If the code isincorrect, or a button is not pressed within twentyseconds, the Set Point Station will automaticallyreturn to the operating mode.

Once within the configuration menu the requiredparameter can be reached by scrolling through themenu using the ▲ or ▼ push buttons as shown inFig 7. When returning to the operating modefollowing recalibration or a change to any function,the Set Point Station will display ‘dAtA’ followed by‘SAVE’ while the new information is stored inpermanent memory.

All new Set Point Stations are supplied calibrated asrequested at the time of ordering. If calibration is notrequested, instruments will be supplied with thefollowing default configuration:

Default Configuration

Resolution ‘rE5n’ 10Display at 4mA output ‘2ero’ 0.00Display at 20mA output ‘5PAn’ 100.00Output current limits ‘H - - L’ 03.000 & 22.000Maximum output rate of change 000P button in operating mode ‘P.Fn’ PCPulses per rev of external encoder ‘EnC’ 12One or two handed operation 'Hnd' '2 H'Security access code ‘CodE’ 0000

Default configuration can easily be changed on-site.

6.1 Summary of configuration functionsThis section summarises each of the configurationfunctions and includes a cross reference to a moredetailed description. Fig 7 illustrates the location ofeach function within the configuration menu.

Display Summary of function

'rE5n' Adjustment resolutionDefines the adjustment resolution of thefront panel ▲ and ▼ buttons and theoptional external rotary control whenadjusting the output current with the SetPoint Station in the operating mode. Maybe set to ‘1’, ‘10’ or ‘100’ least significantdigits of the display.See section 6.2

'dP' Decimal pointPositions a dummy decimal pointbetween any of the displayed digits orturns it off.See section 6.3

‘ CAL’ and ‘SEt’ are alternative ways ofcalibrating the Set Point Station digital display.

'CAL' Calibration of the digital display usingan external current meter.Preferred method of calibrating the digitaldisplay which enables the zero and spanof the Set Point Station display to becalibrated to show the engineering unitsrepresented by the 4/20mA output.Calibration may be performed at anyoutput current providing the points are atleast 4mA apart. Requires an accurateexternal current meter.See section 6.4

'5Et' Calibration of digital display usinginternal references.Using the Set Point Station’s internalreference, this function enables thedigital display to be calibrated to show theengineering units represented by theoutput current at 4mA and 20mA. Unlikethe ‘CAL’ function, an accurate externalcurrent measuring instrument is notrequired and the Set Point Station doesnot have to be disconnected from theloop, but calibration can only beperformed at 4 and 20mA.See section 6.5

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Display Summary of function

'H - - L' High & low current output limitsDefines the lower ‘Lo’ and upper ‘Hi’4/20mA Set Point Station output currentlimits.See section 6.6

'P5Et' Pre-set outputsThe values of the five pre-set currentoutputs are defined by this function. Thepre-set output currents are identified‘5Et1’ to ‘5Et5’ and are displayed inengineering units.This function only appears in theconfiguration menu when ‘P5Et’, whichallows pre-set values to be viewed andselected in the operating mode, isselected in the ‘P.Fn’ function.See section 6.7

'rAtE' Maximum output rate of changeEnables the maximum rate of change ofthe 4/20mA output current to be defined.Adjustable between approximately 1 and100 seconds for full scale output travel.0 disables this rate of change limit.See section 6.8

'P.Fn' Function of P push button inoperating mode.The Set Point Station may be configuredto display the output current in milliamps,the output current as a percentage or toprovide access to the five pre-set outputswhen the P push button is pressed in theoperating mode.See section 6.9

Display Summary of function

'EnC' EncoderIn addition to the Set Point Station4/20mA output being adjusted by thefront panel push buttons, an externalquadrature encoder may be connected toprovide control via a rotary knob. Thisfunction allows the number of pulses perrevolution of the knob to be entered.See section 6.10

'Hnd' One or two handed operationAllows the Set Point Station outputcurrent to be adjusted by the front panel▲ or ▼ push button and by the optionalexternal encoder with or without the Ebutton be pressed at the same time.See section 6.11

'CodE' Security codeDefines a four digit numeric code thatmust be entered to gain access to theconfiguration menu. Default code 0000disables this security function and allowsunrestricted access to all conditioningfunctions.See section 6.12

'r5Et' ResetReturns the Set Point Stationconfiguration to the default condition. Toprevent accidental use, reset must beconfirmed by entering ‘5urE’ before it willbe executed. See section 6.13

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6.2 Adjustment resolution: ‘rE5n’This function enables the adjustment resolution ofthe front panel ▲ and ▼ buttons and the optionalalternative external rotary control to be defined. Oneof three different resolutions may be selected ‘1’, ‘10’or ‘100’ least significant digits of the Set Point Stationdisplay. If ‘10’ is selected the least significantdisplayed digit will always be zero and the secondleast significant digit will change when the front panelE button plus the ▲ or ▼ button are pressed in theoperating mode, or the optional external rotarycontrol is turned. Similarly, if ‘100’ is selected theleast two significant displayed digits will always bezero and the third least significant digit will changewhen the front panel buttons are operated, or theoptional external rotary control is turned.

To define the adjustment resolution select ''rE5n'from the configuration menu and press P which willreveal the current adjustment resolution. To changethe resolution press the ▲ or ▼ button to select 1,‘10’ or ‘100’, followed by the E button to enter theselection and return to the configuration menu.

Notes:a. This function does not affect the resolution of

adjustments made within the configurationmenu.

b. If a pre-set output has a finer resolution than theselected adjustment resolution, the finerresolution will be used to determine the pre-setoutput, but the selected resolution will berestored when the output is adjusted using theE button plus the ▲ or ▼ button in theoperating mode.

6.3 Position of the decimal point: ‘dP’A dummy decimal point can be positioned betweenany of the displayed digits or it may be absent. Toposition the decimal point, select 'dP' from theconfiguration menu and press P. The decimal pointcan be moved by pressing the ▲ or ▼ push button.If a decimal point is not required it should bepositioned beyond the most or least significant digit.When positioned as required press the E button toenter the selection and return to the ‘dP’ prompt inthe configuration menu.

6.4 Calibration of the digital display using anexternal current meter: ‘CAL’This function is the preferred method of calibratingthe Set Point Station digital display to show theengineering units represented by the 4/20mA output.The function enables the Set Point Station outputcurrent to be set at two different values, Zero andSpan, measured by a calibrated external currentmeter and the corresponding Set Point Stationdisplay to be entered.

The bargraph is not displayed while using the ‘CAL’function.

Although calibration is normally performed at4.000mA and 20.000mA, other currents may beused providing they differ by more than 4mA.

To calibrate the Set Point Station display, select'CAL' from the configuration menu and press P toenter the ‘2Ero’ sub-menu used for calibrating thedisplay at the lower of the two output currents,usually 4.000mA. Pressing P again will result in‘Adj’ being displayed which is an invitation to adjustthe Set Point Station output current using the ▲ or▼ push button. Pressing either of these buttons willcause the output current to change, graduallyaccelerating as the button is held. Alternatively theexternal rotary encoder may be used. When theexternal current meter shows the required loweroutput current e.g. 4.000mA, press P to reveal theexisting Set Point Station digital display with one digitflashing. The flashing digit may be adjusted bypressing the ▲ or ▼ button, when this digit is set asrequired pressing P will transfer control to the nextdigit. When all the digits have been adjusted, pressE to enter the setting and return to the '2Ero' prompt.

Calibration of the Set Point Station display at theupper output current is performed in exactly thesame way using the ‘5PAn’ sub-menu which may beselected from the ‘2ero’ prompt using the ▲ or ▼button.

To obtain a reverse acting display i.e. the Set PointStation display decreases as the output currentincreases, the required display value entered into‘2Ero’ should be greater than that entered into‘5PAn’. The ▲ and ▼ buttons on the front of theinstrument always indicate which way the display willchange when the button is pushed.

The bargraph will start at the numerical displayentered for ‘2Ero’ calibration and finish at thenumerical display entered for ‘5Pan’ calibration,except for reverse acting calibration when thebargraph will also be reversed.

Note:a. If the specified ‘2Ero’ and ‘5PAn’ output currents

do not differ by 4 or more milliamps, they will notbe stored when the E button is pressed to returnthe Set Point Station to the operating mode.

6.5 Calibration of digital display using internalreference: ‘5Et’Using the Set Point Station’s internal reference, thisfunction enables the digital display to be calibrated toshow the engineering units represented by the outputcurrent at 4mA and 20mA.

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Unlike the ‘CAL’ function, an accurate externalcurrent measuring instrument is not required and theSet Point Station does not have to be disconnectedfrom the loop, however calibration can only beperformed at 4mA and 20mA. Although nottraceable to a calibrated standard, accuracy isadequate for many industrial applications.

To calibrate the Set Point Station’s digital displayselect 'SEt' from the configuration menu and pressP. The Set Point Station will display '4.000', pressingP again will reveal the calibrated display at 4mAoutput with one digit flashing. The flashing digit maybe adjusted by pressing the ▲ or ▼ buttons, whenthe flashing digit is correct pressing P will transfercontrol to the next digit. When all the digits havebeen adjusted, press E to return to the '4.000'prompt.

Calibration of the Set Point Station display at 20mAoutput is performed in exactly the same way usingthe ‘20.000’ sub-menu which may be selected fromthe ‘4.000’ prompt using the ▲ or ▼ button. Whenthe display corresponding to a 20mA output hasbeen entered pressing E twice will enter the settingand return to the ‘5Et’ prompt in the configurationmenu.

The bargraph is not displayed while using the ‘5Et’function

To obtain a reverse acting display i.e. the Set PointStation display decreases as the output currentincreases, the required display value entered into‘4.000’ should be greater than that entered into’20.000’. The ▲ and ▼ buttons on the front of theinstrument always indicate which way the display willchange when the button is pushed.

The bargraph will start at the numerical displayentered for 4mA output and finish at the numericaldisplay entered for 20mA output, except for reverseacting calibration when it will also be reversed.

6.6 High & low current output limits: ‘H - - L’The BA427E output is normally adjustable between 3and 22mA, but may be restricted by this function if alimited adjustment range is required. e.g. to preventa dangerously high and/or low temperature beingselected when used as the set point input for atemperature controller. When the Set Point Station’soutput current equals the high limit, ‘oVEr’ isdisplayed, similarly ‘undEr’ is displayed when theoutput current equals the low limit.

To restrict the Set Point Station’s output currentrange select 'H - - L' from the configuration menuand press P. Using the ▲ or ▼ button select ‘Lo’ toadjust the lower current output limit, or ‘Hi’ to adjustupper output current limit. Pressing E will display theselected output current limit in milliamps with onedigit flashing.

The flashing digit may be adjusted by pressing the ▲or ▼ button, when the flashing digit is correctpressing P will transfer control to the next digit.When all the digits have been adjusted press E toreturn to the 'Lo' or ‘Hi’ prompt followed by E to enterthe adjustments and return to the ‘H - - L’ prompt inthe configuration menu.

Notes:a. The Lo limit can not be adjusted to a value

above the present Set Point Station outputcurrent, and the Hi limit can not be adjusted to avalue below the present Set Point Station outputcurrent. The actual Set Point Station outputcurrent should therefore be adjusted to withinthe acceptable output range before the Lo andHi limits are adjusted.

b. If any of the five pre-set output currents are setbelow the Lo limit or above the Hi limit, they willnot be selectable and ‘oVEr’ or ‘undEr’ will bedisplayed.

6.7 Pre-set outputs: ‘P5Et’Up to five pre-set current outputs may be stored andrecalled from the front panel push buttons whichenables common output currents to be quicklyselected. e.g. frequently used operatingtemperatures when a BA427E is used as the setpoint input for a temperature controller.

To enter pre-set values select ‘P5Et’ from theconfiguration menu and press P which will result in‘5Et 1’, the first pre-set sub-menu being displayed,pressing P will then reveal the present value inengineering units with one digit flashing. The flashingdigit may be adjusted by pressing the ▲ or ▼ button,when the flashing digit is correct pressing P willtransfer control to the next digit. When all the digitshave been adjusted, press E to return to the '5Et 1'prompt from which any of the other four pre-setsmay be selected via the ▲ or ▼ button and adjustedin the same way as ‘5Et 1’.

Notes:a. ‘P5et’ only appears in the configuration menu

when ‘P5Et’ is selected in the ‘P.Fn’ menuwhich defines the function of the P push buttonin the operating mode. see section 6.9.

b. Maximum adjustment resolution is alwaysavailable for inputting pre-set values and isused to determine the current output when thepre-set is selected, irrespective of theadjustment resolution selected in function‘rE5n’ – see 6.2

c. If, after calibration of the Set Point Stationdisplay, previously entered pre-set values areoutside the revised output current range, whenselected the pre-set value alternating with‘oVEr’ or ‘undEr’ will be displayed.

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6.8 Maximum output rate of change: ‘rAtE’To minimise plant disturbance when the Set PointStation output current is adjusted, the maximum rateof change is defined by this function. The maximumrate is adjustable between approximately 1 and 100seconds for full scale output travel from 4 to 20mA.If 0 seconds is selected the function is disabled.

To define the maximum rate of change of the SetPoint Station output select 'rAtE' from theconfiguration menu and press P which will reveal thepresent maximum rate of change in seconds withone digit flashing. The flashing digit may be adjustedby pressing the ▲ or ▼ buttons, when the flashingdigit is correct pressing P will transfer control to thenext digit. When all the digits have been adjusted,press E to enter the new value and return to theconfiguration menu.

When the output rate of change limitation isfunctioning, in the operating mode the Set PointStation digital display will show the requested outputand will flash until the requested output current isachieved. The bargraph display always shows theSet Point Station’s actual output.

Pressing the E button while the output is ramping toa new requested value will stop the output changing.

6.9 Function of the P push-button in operatingmode: ‘P.Fn’Using this function the Set Point Station may beconfigured to display the output current in milliamps,the output current as a percentage of the outputrange, or to provide access to the five pre-setoutputs when the P button is pressed in theoperating mode.

To check or change the function of the P push buttonselect 'P.Fn' from the configuration menu and pressP to reveal the present setting. Pressing the ▲ or ▼button will scroll the setting between:

'PC' Output as a percentage of output range.

'4-20' Output current in milliamps

‘P5Et’ Access to the five pre-set outputssee 6.7

When set as required, press E to return to the ‘P.Fn’prompt in the configuration menu.

6.10 Encoder: ‘EnC’For applications requiring the Set Point Station’s4/20mA output current to be controlled by a rotaryknob, an external three wire quadrature encoder maybe directly connected to terminals 5, 6 and 7.

The BEKA BA490 Is a panel mounting encoder thatgenerates 12 contact pulses per revolution whichcomplies with the requirements for simple apparatusand is intended for use with the BA427E. Otherencoders that produce a different number of contactpulses per revolution may also be used. So that allexternal encoders have a similar adjustmentresolution, the ‘EnC’ function enables the number ofpulses between 6 and 48 per revolution to bedefined.

To enter the number of pulses per revolution that theexternal encoder generates, select 'EnC' from theconfiguration menu and press P which will reveal theexisting setting with one digit flashing. The flashingdigit may be adjusted by pressing the ▲ or ▼ button,when the flashing digit is correct pressing P willtransfer control to the other digit. When both digitshave been adjusted press E to return to the ‘EnC’prompt in the configuration menu.

Section 8.4 contains information about the use of anexternal rotary encoder.

6.11 One or two handed operation: ‘Hnd’This function defines whether the front panel Ebutton has to be pushed at the same time that the ▲or ▼ button is operated, or the optional externalencoder is rotated to adjust the Set Point Station'soutput current. Selecting the two handed operationwhich requires the E button to be operated whichminimises the possibility of accidental adjustment.

To check or change the function select 'Hnd' fromthe configuration menu and press P to reveal theexisting setting. Pressing the ▲ or ▼ button willtoggle between the two setting:

'2 H' Output current can only be adjusted when the E button is pressed..

'1 H' Output current can be adjusted without pressing the E button.

When set as required, press E to return to the ‘Hnd’prompt in the configuration menu.

6.12 Security code: ‘CodE’Access to the instrument configuration menu may beprotected by a four digit security code which must beentered to gain access. New instruments areconfigured with the default security code 0000 whichallows unrestricted access to all configurationfunctions.

To enter a new security code select 'CodE' from theconfiguration menu and press P which will cause theSet Point Station to display the existing security codewith one digit flashing. The flashing digit can beadjusted using the ▲ and ▼ push buttons, when setas required operating the P button will transfercontrol to the next digit.

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When all the digits have been adjusted press E toreturn to the ‘CodE’ prompt. The revised securitycode will be activated when the Set Point Station isreturned to the operating mode. Please contactBEKA associates sales department if the securitycode is lost.

6.13 Reset to factory defaults: ‘rSEt’This function quickly returns to the BA427E Set PointStation to the factory default configurations shown insection 6.

To reset the Set Point Station select ‘rSEt’ from theconfiguration menu and press P. To preventaccidental resetting the request must be confirmedby entering ‘5urE’. Using the ▲ button set the firstflashing digit to ‘5’ and press P to transfer control tothe second digit, which should be set to ‘u’. When‘5urE’ has been entered pressing the E button willreset the configuration menus and return the displayto the ‘rSEt’ function in the configuration menu.

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7. MAINTENANCE

7.1 Fault finding during commissioningIf a BA427E Set Point Station fails to function duringcommissioning the following procedure should befollowed:

Symptom Cause SolutionNo loop current Incorrect wiring Check wiring

There should be 6.1 to 30V between terminals 1 & 3 with terminal1 positive. With an optional backlight which is loop powered, there should be 10V to 30V between terminals3 & 12 with terminal 12 positive.

No loop current0V between terminals 1 & 3 or between terminals3 & 12 if optional backlight is loop powered.

Incorrect wiring or no power supply

Check supply voltage and voltage drop caused by all the instruments in the loop.

Unable to adjust output current using ▲ or ▼ push buttons or the optional external encoder.

Instrument may be configured for 2 hand operation and require E button to be operated at the same time.

Check 'Hnd' function in configuration menu and change if necessary.

Unstable 4/20mA loop current.

Noisy power supply or insufficient voltage to powerall the instruments in the loop.

Eliminate ripple onpower supply or increase supply voltage.

Unable to enter configuration menu.

Incorrect security code entered.

Enter correct security code, or contact BEKA if the code has beenlost.

BA427E displays‘LP Lo’

Voltage betweenBA427E terminal 1 & 3 istoo low,

Increase 4/20mA loop supply voltage.

7.2 Fault finding after commissioning

ENSURE PLANT SAFETY BEFORESTARTING MAINTENANCE

Live maintenance is permitted onintrinsically safe equipment installedin a hazardous area, but onlycertified test equipment should beused unless a gas clearancecertificate is available.

If a BA427E Set Point Station fails after it has beenfunctioning correctly follow the procedure shown insection 7.1. If this does not reveal the cause of thefault, it is recommended that the Set Point Station isreplaced.

7.3 ServicingWe recommend that faulty BA427E Set PointStations are returned to BEKA associates or to ourlocal agent for repair.

7.4 Routine maintenenceThe mechanical and electrical condition of theinstrument should be regularly checked. Initiallyannual inspections are recommended, but theinspection frequency should be adjusted to suit theenvironmental conditions.

7.5 GuaranteeSet Point Stations which fail within the guaranteeperiod should be returned to BEKA associates or ourlocal agent. It is helpful if a brief description of thefault symptoms is provided.

7.6 Customer commentsBEKA associates is always pleased to receivecomments from customers about our products andservices. All communications are acknowledged andwhenever possible, suggestions are implemented.

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8. ACCESSORIES8.1 Scale cardThe BA427E Set Point Station has a window on theright hand side of the display through which the scalecard showing the units represented by the outputcurrent such as ºC or mBar can be seen. New SetPoint Stations are fitted with a scale card showingthe units specified when the instrument was ordered,if the units are not specified when the instrument isordered a blank scale card will be fitted. A pack ofscale cards pre-printed with common units ofmeasurement is available as an accessory. Thesecan easily be fitted to the Set Point Station withoutopening the instrument enclosure or removing it fromthe panel, See section 5.4 of this instruction manual.

Custom scale cards for applications requiring lesscommon units of measurement are also available.

8.2 Tag informationNew Set Point Stations can be supplied with tag orapplication information thermally printed onto therear panel adjacent to the terminals. This taginformation is not visible from the front of theinstrument after installation.

8.3 Display backlightThe BA427E Set Point Station can be supplied with afactory fitted green backlight that may be loop orseparately powered.

When loop powered the backlight producesbackground illumination enabling the display to beread at night or in poor lighting conditions. Noadditional power supply, intrinsic safety interface orfield wiring are required, but the Set Point Station’sminimum operating voltage is increased. Whenseparately powered the backlight is brighter, but anadditional intrinsic safety interface and field wiringare required.

Fig 8 Terminals for optional backlight

8.3.1 Loop powering the backlightThe backlight is loop powered by connecting it inseries with the Set Point Station’s 4/20mA output asshown in Fig 9, which increases the minimumoperating voltage to 10V.

Fig 9 Loop powered backlight

The input intrinsic safety parameters of thecombined Set Point Station and backlight are thesame as for the Set Point Station alone. Providingthe increased voltage drop can be tolerated, theintrinsic safety and system design described insections 3 and 4 of this manual remain valid with thebacklight loop powered.

8.3.2 Separately powering the backlightThe optional backlight may also be powered from aseparate safe area power supply via an intrinsicallysafe interface as shown in Fig 10.

Fig 10 Separately powered backlight

When separately powered the backlight draws aconstant current of 22.5mA at or above 9V. Belowthis voltage the backlight continues to function butwith reduced brilliance. Powering the backlight froman adjustable voltage supply allows the backlightbrilliance to be adjusted which is a useful featurewhen the operator’s night vision has to be preserved.

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Any certified Zener barrier or galvanic isolator maybe used to separately power the backlight, providingthe output parameters do not exceed:

Uo = 30V dcIo = 200mAPo = 0.84W

The internal capacitance Ci between terminals 12 &14 should be subtracted from Co of the intrinsicallysafe interface powering the backlight to determinethe maximum permissible cable capacitance.

Ci = 11nFLi = 0

Two separately powered BA427E Set Point Stationbacklights may be connected in parallel to a singlechannel 28V, 93mA Zener barrier or galvanic isolatorwith no noticeable reduction in brilliance whenpowered from a 24V dc supply.

8.4 External encoderFor applications requiring the output of the BA427ESet Point Station to be controlled externally,terminals 5, 6 and 7 enable a wide range of threewire quadrature encoders with switch contact outputsto be directly connected to the BA427E. Whetherthe E button must be operated to enable the encoderto adjusts the Set Point Station’s output isdetermined by the 'Hnd' function.. See section 6.11.

The Set Point Station’s output current can still becontrolled by the ▲ and ▼ buttons when an externalencoder is connected.

8.4.1 Intrinsic safetyThe intrinsic safety parameters for the externalencoder terminals 5, 6 and 7 are:

Ui = 30V dcIi = 200mAPi = 0.84W

Uo = 5.0V dcIo = 1.0mAPo = 1.25mW

Equivalent maximum capacitance and inductancebetween the three encoder terminals 5, 6 and 7 is:

Ci = 0Li = 0

These parameters are not restrictive and allow awide range of three wire quadrature encoders with aswitch contact output to be directly connected to theBA427E Set Point Station.

8.4.2 System design for hazardous areasThe external encoder must be certified intrinsicallysafe with input parameters equal to or greater than:

Ui = 5.0V dcIi = 1.0mAPi = 1.25mW

or output parameters equal to or less than:

Uo = 30V dcIo = 200mAPo = 0.84W

Alternatively, the encoder must comply with therequirements for simple apparatus as specified inClause 5.7 of EN 60079-11. Most encoderscomprising of just two mechanically activatedswitches will comply with these requirements. See8.4.3.

8.4.3 BEKA BA490 rotary encoderThe BEKA BA490 quadrature output RotaryEncoder has been designed to operate with aBA427E Set Point Station. It is an IP66 panelmounting device with a 20mm diameter control knobwhich complies with the requirements for SimpleApparatus. The two output waveforms are shown inFig 12.

Fig 12 BA490 rotary encoder output waveforms

Interconnections between the BA427E Set PointStation and the external BA490 Rotary Encoder areshown below.

BA427E BA490 Terminal Nos, Terminal Nos,

5 A6 B7 C

The BA490 Rotary encoder must be located in the same hazardous area as the BA427E Set Point Station and the wiring between them must have 500V ac insulation to earth.

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APPENDIX 1Dust certification

A1.0 ATEX dust certificationIn addition to ATEX certification permittinginstallation in explosive gas atmospheres which isdescribed in the main section of this instructionmanual, all BA427E Set Point Stations have ATEXcertification permitting installation in combustibledust atmospheres.

This appendix describes ATEX installations inexplosive dust atmospheres conforming withEN 60079-14 Electrical installations design, selectionand erection. When designing systems forinstallation outside the UK the local Code of Practiceshould be consulted.

The Set Point Station’s dust input and output safetyparameters are identical to the gas safetyparameters, so all the electrical circuits shown in themain section of this manual may also be used fordust applications.

A1.1 Zones, and Maximum SurfaceTemperature

The BA427E has been ATEX certified as Group II,Category 1D Ex ia IIIC T80ºC Da IP20 apparatus, Ta-40 to 70°C.

When connected to a suitable system the Set PointStation may be installed in:

Zone 20 explosive atmosphere in the form of acloud of combustible dust in air iscontinuously present, or for longperiods or frequently.

Zone 21 explosive atmosphere in the form of acloud of combustible dust in air islikely to occur occasionally in normaloperation.

Zone 22 explosive atmosphere in the form of acloud of combustible dust in air is notlikely to occur in normal operation, butif it does occur, will only persist for ashort period.

Be used with dust in subdivisions:

IIIA combustible flyings

IIIB non-conductive dust

IIIC conductive dust (For use with IIIC conductive dusts special conditions for safe use apply – see section A1.4)

Having a Minimum Ignition Temperature of:

Dust cloud 120°C

Dust layer on Set Point 155°CStation up to 5mm thick.

Dust layer on Set Point Refer toStation over 5mm thick. EN 60079-14

At an ambient temperature between -40 and +70°C

A1.3 Maintenance

ENSURE PLANT SAFETY BEFORESTARTING MAINTENANCE

Live maintenance is permitted onintrinsically safe equipment installed in ahazardous area, but only certified testequipment shall be used.

The BA427E Set Point Station has IP66 front ofpanel protection and a gasket is provided to seal thejoint between the instrument and the mounting panel,thus preventing dust ingress from the outside of themounting panel. The rear of the instrument is notsealed as the ATEX dust certification relies on theinternal conformal coating of the instrument. Dustingress to the rear terminals is acceptable except foruse in IIIC conductive dusts – see A1.4. However, itis good practice to minimise the amount of dustaccumulating on the rear of the instrument and theterminals.

A1.4 Special conditions for use in IIIC dustsThe BA427E Set Point Station ATEX certificate hasan ‘X’ suffix indicating that special conditions for safeuse are required for installion in IIIC dustatmospheres, the certificate states:

‘For use in Group IIIC conductive dustatmospheres, the Set Point Station shall bemounted such that the instrumentterminals have at least IP6X protection.’

To prevent the BA427E Set Point Station terminalsbecoming contaminated by conductive dust:

The BA427E must be installed in a panel,cubicle or enclosure providing a minimum ofIP6X protection.

The panel cut-out dimensions must be asshown in Fig 4 and the supplied gasket mustbe used.

Note: These special installation conditions only applyfor instruments exposed to IIIC conductive dustatmospheres.

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APPENDIX 2IECEx certification

A2.0 The IECEx Certification SchemeIECEx is a global certification scheme for explosionprotected products which aims to harmoniseinternational certification standards. For additionalinformation about the IECEx certification schemeand to view the BEKA associate certificates, pleasevisit www.iecex.com

A2.1 IECEx Certificate of ConformityThe BA427E Set Point Station and the optionalaccessories have been issued with an IECExCertificate of Conformity numberIECExITS12.0084X which specifies the followingcertification codes:

Ex ia IIC T5 GaEx ia IIIC T80ºC Da IP20Ta = -40ºC to 70ºC

The specified gas and dust intrinsic safetyparameters are identical to the ATEX safetyparameters described in this manual.

The IECEx certificate may be downloaded fromwww.beka.co.uk, www.iecex.com or requested fromthe BEKA sales office.

A2.2 InstallationIECEx and ATEX certificates specify identical safetyparameters and installation requirements for bothapprovals as defined by IEC / EN 60079-14. TheATEX gas and dust installation requirementsspecified in section 5 and Appendix 1 of this manualmay therefore be used for IECEx installations, butthe local code of practice should also be consulted.

A2.3 Special conditions for use in IIIC dustsThe IECEx certificate for the BA427E Set PointStation has an ‘X’ suffix indicating that specialconditions for safe use are required for installion inIIIC dust atmospheres, the certificate states:

‘For use in Group IIIC conductive dustatmospheres, the Set Point Station shall bemounted such that the instrumentterminals have at least IP6X protection.’

To prevent the BA427E Set Point Station terminalsbecoming contaminated by conductive dust:

The BA427E must be installed in a panel,cubicle or enclosure providing a minimum ofIP6X protection.

The panel cut-out dimensions must be asshown in Fig 4 and the supplied gasket mustbe used.

Note: These special installation conditions only applyfor instruments exposed to IIIC conductive dustatmospheres.

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Appendix 3cETL Mark for installations in USA and Canada

A3.0 cETL MarkFor installations in the USA and Canada, theBA427E Set Point Station has cETL intrinsic safetyand nonincendive approval, Control Number4008610. Copies of the Authorisation to Mark areavailable from the BEKA associates sales office andwww.beka.co.uk

A3.1 Intrinsic safety approvalThe US and Canadian standards used forassessment and certification of the BA427E arelisted on the ETL Authorisation to Mark.

Installations must comply with BEKA associatesControl Drawing CI400-12, which is attached to thisappendix, ANSI/ISA RP12.06.01 ‘Installation ofIntrinsically Safe Systems for Hazardous (Classified)Locations’ and with the National Electrical CodeANSI/NFPA70. Installations in Canada must complywith the Canadian Electrical Code C22.2

The front of the Set Point Station has IP66 (Type 4)protection. To obtain an IP66 seal between the SetPoint Station and the panel in which it is mounted,the installation must comply with note 7 of ControlDrawing CI400-12.

The BA427E has a T5 rating at ambienttemperatures between -40ºC and +70ºC and may beinstalled in the following Divisions and Zones andmay used with the following gases:

Intrinsic SafetyDivision 1 or 2

Class I Group A & B Group C Group D

Zone 0, 1 or 2Class I Group IIC Group IIB Group IIA

The ETL entity parameters are the same as theATEX and IECEx parameters, the systems shown insection 4 of this manual may therefore also be usedfor US and Canadian installations subject to localcodes of practice.

A3.2 Nonincendive approvalThe BA427E also has ETL nonincendive approvalallowing installation in Division 2 and Zone 2hazardous (classified) locations without the need forZener barriers or galvanic isolators. US installationsmust comply with the BEKA associates ControlDrawing CI400-13, which is attached to thisappendix, and with the National Electrical CodeANSI/NFPA70.

Canadian nonincendive installations must complywith BEKA associates Control Drawing CI400-13,which is attached to this appendix and the CanadianElectrical Code C22.2.

The front of all the BA427E has IP66 (Type 4)protection. To obtain an IP66 seal between the SetPoint Station and the panel in which it is mounted,the installation must comply with note 5 of ControlDrawing CI400-13.

The BA427E has a T5 rating at ambienttemperatures between -40ºC and +70ºC and may beinstalled in Division 2 or Zone 2 and used with thefollowing gases, dusts, fibres and flyings:

NonincendiveDivision 2

Class I Group A & B Group C Group D

Class II Groups E, F & G

Class IIIZone 2

Class I Group IIC Group IIB Group IIA

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