Safety, Operation, and Procedure Instructions for the VLF Series of AC Hipots ***** Caution- High Voltage ***** This Operator Manual contains instructions for the operation of a High Voltage power source. The operator of this equipment must use good judgement and follow all safety precautions noted in this guide to ensure the protection of himself and others in close proximity to the test area. Failure to follow the instructions could result in injury or death. Proper grounding of the test set must be done prior to connecting this unit to a power source. Min e VL F SERIES
Transcript
Safety, Operation, and Procedure Instructions for the VLF Series of AC Hipots
***** Caution- High Voltage ***** This Operator Manual contains instructions for the operation of a High Voltage power source. The operator of this equipment must use good judgement and follow all safety precautions noted in this guide to ensure the protection of himself and others in close proximity to the test area. Failure to follow the instructions could result in injury or death. Proper grounding of the test set must be done prior to connecting this unit to a power source.
Last saved 8/21/2014 T:\DOCUMENTS\Manuals\VLF\archive\MANvlf2.doc
Table of Contents
About the Operator Manual 1
S E C T I O N 1
General Information 2
Features and Specifications 2-4
Controls and Indicators 5-7
List of Components 7
S E C T I O N 2
Setting up the Equipment 8,9
Typical VLF Connection Scheme 10
Operating the Equipment 11-13
Blank Page for Notes 14
S E C T I O N 3
Performing Special Operations 15
Voltmeter Re-calibration 15,16
Miscellaneous 16 Packing the cables 16
O P E R A T O R M A N U A L
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About the Operator Manual
Important
This Operator Manual describes the features and safe operation of a High Voltage AC Test Set. The instructions are intended to be clear and simple, but the operator must be trained and qualified according to the customer’s established procedures for the use of this type of equipment.
This Operator Manual is organized to provide information on the VLF Series in steps that familiarize the new operator with the entire scope of operation of this test set.
Section 1: Specifications and Controls.
Section 2: Setup and Operation.
Section 3: Performing Special Operations.
The Functions, Features, and Specifications of the VLF Series of AC Hipots are also discussed in the VLF
Brochure available from High Voltage, Inc.
O P E R A T O R M A N U A L
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General Information This section familiarizes the operator with the features and specifications of the
VLF Series of Portable AC Hipots manufactured by HIGH VOLTAGE, INC.
Features and Specifications The VLF Series of hipot test sets provide true sine wave AC output voltage for the test of high voltage cables and other capacitive loads.
Standard features of the VLF Series of AC Hipots
Sine wave output, 0.1, 0.05 and 0.02 Hz frequencies standard.
Continuously adjustable output voltage
Continuous duty rating
Fixed thermal circuit breaker overload
“Zero Start” and External Interlock provision
Single-range voltmeter
Two piece portable design
Transit protected meter prevents damage between test sites
Ground stick provided for increased operator safety. Can be used to safely connect the unit and the test load to ground before and after test
Output limit resistor
10 ft. input line cord
10 ft. interconnect cable with grounds
SECTION
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20 ft. RG8/U output cable(VLF-4022), 12 ft. shielded X-Ray output cable(VLF-6022)
Hook type output connector
Alligator clip type output connector
WARNING
DO NOT OPERATE THE VLF HIPOT SET IF THE HIGH VOLTAGE TANK IS 5 OR MORE FROM LEVEL.
IF THE UNIT IS OPERATED OUT OF LEVEL, OVERHEATING AND INTERNAL ARCING MAY OCCUR.
DO NOT STORE OR TRANSPORT VLF HIGH VOLTAGE SECTION
ON IT’S SIDE
O P E R A T O R M A N U A L
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MODEL VLF AC HIPOT SPECIFICATIONS
VLF-4022( 40 kV,2.2 F)
Part No. VLF-1034S(115V)
Part No. VLF-1041S(F-230V)
VLF-6022(60 Kv,2.2f)
Part No. VLF-1033S(115V)
Part No. VLF-1032S(F-230V)
Input 120 V, 50/60 Hz, 10 A peak, 5 A avg.
230 V, 50/60 Hz, 5 A peak, 2.5 A avg.
120 V, 50/60 Hz, 15A peak, 7.5 A avg.
230 V, 50/60 Hz, 8 A peak, 4 A avg.
Output Sinusoidal 0-40 kVac peak, 0.1, .05, and .02 Hz frequency
Sinusoidal 0-60 kVac peak, 0.1, .05, and .02 Hz frequency
Duty Continuous Continuous
Test Capacitance 1.1 F @ .1 Hz, 2.2F @ .05 Hz, 5.5 f @ .02 Hz
Kilovoltmeter 3.5 in. , 0-40 PEAK KILOVOLTS 3.5 in. , 0-60 PEAK KILOVOLTS
Control Case Size
High Voltage Tank size
19w x 11d x 15.5 high
13.5w x 8.5d x 19 high
19w x 11d x 15.5 high
14.4w x 10.25d x 21.5 high
Control Case Weight
High Voltage Tank Weight
50 lbs. (22kg)
72 lbs. (31kg)
55 lbs. (25kg)
100 lbs. (45kg)
Interconnect cable length
Output cable length
10 ft.
RG8/U 20 ft.
10 ft.
Shielded X-Ray 12 ft.
Table 1 VLF Series Specifications.
O P E R A T O R M A N U A L
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Figure 1 VLF Series front panel controls.
I N P U T P O W E R The INPUT POWER connector accepts most standard line/extension cords. The power supplied to the input connector must be from a grounded source rated to match the input power specifications noted in Table 1.
M A I N P O W E R The MAIN POWER pushbutton switch provides the power to the control and power circuits. The neon lamp in the switch will light when the power is on and voltage is available through input line cord. The INPUT FUSE located electrically before the MAIN POWER switch provides input line protection for the unit.
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E X T . I N T L K ( E X T E R N A L I N T E R L O C K ) The Ext. Intlk. connector is provided to allow for a normally open safety interlock switch to control the energizing of the high voltage output.
H V O V E R L O A D The HV OVERLOAD circuit breaker protects the variable transformer output control brush. Its thermal characteristics allow for the short term overload of the variable transformer while still providing proper protection.
H I G H V O L T A G E O N / O F F The HIGH VOLTAGE ON (OFF) pushbuttons activate (de-activate) the high voltage power circuits. The LED indicators provide long life positive indication of the circuit status. The RED (ON) LED lights when high voltage is energized, the GREEN (OFF) LED lights when the high voltage is de-energized.
O U T P U T C O N T R O L The OUTPUT control variable transformer adjusts the output voltage. The 0-10 markings on the knob indicate the low to high setting. The control must be at ZERO (0) to energize the high voltage circuits. The output control must always be returned to zero at the completion of testing, prior to de-energizing the output , allow the unit to cycle for 60 seconds to assure full discharge of the load.
V O L T M E T E R The KILOVOLT METER allows for accurate output voltage readings. 1-% precision resistors minimize the need for re-calibration due to aging shift. See Voltmeter Re-calibration in Section 3 for details on calibration.
S C O P E O U P U T The SCOPE OUTPUT allows for accurate output voltage monitoring. This connector can be fed into an oscilloscope for the looking at the actual output wave shape. The peak to peak voltage representing 40 kVac is 8 volts peak/peak. (On the VLF-6022, 60 kVac is 6 volts peak/peak.)
O U T P U T F R E Q U E N C Y The OUTPUT FREQUENCY switch adjusts between calibrated frequencies for testing loads larger than normal .By allowing slower frequencies the output waveshape is maintained. Output frequency choices are .1 Hz for 1.1 F, .05 Hz for 2.2 F, and .02 Hz for 5.5 F.
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Operation of the Timer In the VLF Hipot The Dwell Timer included in our VLF Series of AC Hipots will function as an end of test alarm only. The timer will start upon initiation of the high voltage. The timing function will count up to the preset value. Upon reaching the dwell time, an alarm will sound indicating the need to return the Output Control to zero. Turn off the high voltage, as noted later n the Operating Manual, by allowing the output discharge solenoids and polarity solenoids to cycle at least ten more seconds (one full cycle). To set the timer. Place the left digit to 'J' mode. This sets the timer up to count down and hold the count if the output should arc and shut down. The right digit is for setting the time increments. Settings from .1 second to 10 hour multipliers are possible. The CO and CR timer functions are not used for the dwell timing functions.
List of included components with the VLF Hipot
� Ground stick with 20 ft. of ground wire
� Ext. Intlk. jumper plug
� 20 ft. long output cable RG8/U; VLF-4022 , 12 ft. long X-Ray cable; VLF-6022
� Limit Resistor
� Alligator clip and hook terminations
� 10 ft. input line cord
� 10 ft. interconnect cable with grounds
� BNC to BNC scope to panel interconnect coax cable
WARNING
DO NOT OPERATE THE VLF HIPOT SET IF THE HIGH VOLTAGE TANK IS 5 OR MORE FROM LEVEL.
IF THE UNIT IS OPERATED OUT OF LEVEL, OVERHEATING AND INTERNAL ARCING MAY OCCUR.
DO NOT STORE OR TRANSPORT VLF HIGH VOLTAGE SECTION
ON IT’S SIDE
O P E R A T O R M A N U A L
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SETTING UP THE EQUIPMENT
The setup of this equipment has been minimized by careful consideration of the operator during design. The VLF Series’ two-piece construction allows for convenient portability for AC testing in the field.
Select a location for the unit that will allow easy viewing of the control panel at a safe distance from the test object. Place the high voltage tank within 10 ft. of the control on a level area. The cooling and filter assembly of the VLF series will not operate properly if the high voltage tank is placed on uneven ground. A maximum angle for correct operation is 5. Blocking the tank to a level condition is acceptable.
1. Be sure that all the controls are off, in their de-energized or fully counterclockwise position.
2. Secure a ground test lead to the panel. The Ground post on the front panel should be used for that purpose. A black test lead with black boot has been provided for the ground connection. The clip end should be connected to a solid earth ground.
3. Secure a ground test lead to HV TANK. The Ground stud the top of the tank should be used for that purpose. A black test lead with black boot has been provided for the ground connection. The clip end should be connected to a solid earth ground. A second ground lead is provided for load return and should be connected to the cable shield under test.
4. Connect the ground stick to a solid earth ground.
5. Secure the interconnect cable to both the control and the high voltage tank. Be sure the free-hanging fan/pump connector is also connected to the side connector.
6. Insert the coaxial output cable into the high voltage output connector on the tank. Finger tighten the clamping nut securely.
7. Install the output limit resistor on the output cable. The alligator clip or hook connectors will screw into the limit resistor for connection to the load.
SECTION
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8. Insert the EXT INTLK plug into the socket on the panel. The plug may also be wired to a normally open contact of a safety switch for added protection.
The setup of the VLF AC Test Set does not address the need for proper safety grounding of the load (test sample or cable). The grounding requirements vary for different types of tests. Please consult the local codes where applicable or reference the guidelines for grounding found under OPERATING THE EQUIPMENT.
Operation of the Timer In the VLF Hipot(suffix 'T') The Dwell Timer included in our VLF Series of AC Hipots will function as an end of test alarm only. The timer will start upon initiation of the high voltage. The timing function will count up to the preset value. Upon reaching the dwell time, an alarm will sound indicating the need to return the Output Control to zero and turn off the high voltage, as noted in the Operating Manual, by allowing the output discharge solenoids and polarity solenoids to cycle at least ten more seconds (one full cycle). The timer supplied will be settable from .1 second to 10 hour increments. The timer will automatically reset when the high voltage turns off.
WARNING
DO NOT OPERATE THE VLF HIPOT SET IF THE HIGH VOLTAGE TANK IS 5 OR MORE FROM LEVEL.
IF THE UNIT IS OPERATED OUT OF LEVEL, OVERHEATING AND INTERNAL ARCING MAY OCCUR.
DO NOT STORE OR TRANSPORT VLF HIGH VOLTAGE SECTION
ON IT’S SIDE
O P E R A T O R M A N U A L
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Capacitance Frequency
1.1F or less .1Hz
2.2F or less .05Hz
5.5 F or less .02Hz
O P E R A T O R M A N U A L
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Operating the Equipment
This section provides step-by-step instruction on various test methods. Many facilities have their own in-house test procedures, and this manual is not to supercede these. The purpose of this section is to explain the capabilities of this test set in real-world applications.
AC Insulation Testing 1. Ensure that all the steps listed in Setting up the Equipment have been accomplished. Take
special note to ground the control panel to a solid earth ground using the supplied black test lead. Then connect the GROUND HOOK to the same earth ground.
2. Prior to connecting the output cable to the test sample, ground the test sample using the GROUND STICK supplied with the VLF unit. Remove this ground prior to starting high voltage testing.
3. Connect the output lead to the test sample. Be sure that there is enough clearance to grounded objects for the expected test voltage. The minimum clearance in air is 10 kV ac/inch.
4. Connect the input power cord to a grounded 120 v, 50/60 Hz source(230 v on 'F' units). A generator is an acceptable power source. If the distance to a power source is greater than the cord provided, most standard grounded extension cords will fit the INPUT POWER connector.
5. An oscilloscope (optional) can be connected to the SCOPE OUTPUT for wave shape monitoring. The oscilloscope should be properly grounded and the input should be set to 1 volt/ division, the time base should be 5 seconds/division and the trigger should be set to roll display to view the wave shape. An oscilloscope with signal memory display is best used for this application. A BNC to BNC shielded jumper should be used for connection between the SCOPE OUTPUT and the oscilloscope. A digital meter can be used to monitor this connector. The voltage feedback calibration for this connector is 1 volt for 10 kV of output
* * * C A U T I O N * * *
P O T E N T I A L L Y L E T H A L V O L T A G E S M A Y B E P R E S E N T
O P E R A T O R M A N U A L
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6. With the OUTPUT control at zero (zero start interlock engaged), depress the HV ON
pushbutton. The HV ON light will glow. At this time the pump and fan on the high voltage section will also energize. Do not be startled if the pump makes some noise, this is normal.
7. Increase the output by rotating the OUTPUT control slowly clockwise until the desired output voltage is reached. Raising the output too fast may trip the output overload. Please recognize that the output cycle is 20 seconds for a full sine wave(.05 Hz). To set the output voltage you may need more than one cycle to read the output accurately. There are also .02 and .1 Hz frequency outputs.
8. Maintain the output voltage for the test time specified in your standard procedures.
9. After the test is complete, rotate the OUTPUT control to zero, allowing the load to return to zero and the unit to cycle for about 60 more seconds prior to depressing the HV OFF pushbutton. Allowing the unit to cycle for some time allows for the complete discharge of the load and avoiding the normal self recharge that capacitive loads will exhibit.
10. If the test sample fails during the test, the overload circuit will de-energize the high voltage. Should an overload occur, the normal sine wave cycle is interrupted and the load will bleed down much more slowly than when the unit is cycling normally.
11. Prior to removing the output cable from the load, observe that the output voltmeter is at zero, and then use the GROUND STICK to positively ground the test sample, by first touching the unit side of the output limit resistor, then the load side of the output limit resistor.
WARNING
DO NOT OPERATE THE VLF HIPOT SET IF THE HIGH VOLTAGE TANK IS 5 OR MORE FROM LEVEL.
IF THE UNIT IS OPERATED OUT OF LEVEL, OVERHEATING AND INTERNAL ARCING MAY OCCUR.
DO NOT STORE OR TRANSPORT VLF HIGH VOLTAGE SECTION
ON IT’S SIDE
O P E R A T O R M A N U A L
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AC Testing of High Voltage Cables When testing cables, either single or three phase, there are certain extra steps that must be observed to ensure safe operation.
1. Make sure that all insulators, stress cones, and pot heads are clean and free of moisture. This will prevent flashover and minimize leakage.
The shields of all cables must be securely tied to ground at the nearest end of the cable.
2. Isolate the far end of the conductors under test for the test voltage; that may mean separating some of the conductors in a multi-conductor cable from each other and their shields.
3. Any conductors or wires in the cable or the vicinity not being tested must be grounded to avoid a buildup of charge and possible shock hazard.
4. Voltage must be applied according to specifications from the cable manufacturer or any other applicable test standards.
5. The WAVE SHAPING DISCHARGE SOLENIODS in the oil filled high voltage tank will support a discharge of a 2.2F capacitor (.05Hz). This may restrict the test of exceedingly long cable lengths (over 4 miles). Please use caution if you think the cable is approaching this length. Testing at lower voltages and observing the wave shape at the SCOPE connection will help determine if the internal wave shaping solenoids and resistors are not maintaining a sine wave output. If the cable is too long (load too large) the overload will trip soon after testing has begun.
* * * C A U T I O N * * *
P O T E N T I A L L Y L E T H A L V O L T A G E S M A Y B E P R E S E N T
STORED ENERGY LEVELS IN THE CABLE GREATLY INCREASE THE RISK OF FATAL INJURY IF CONTACT IS MADE WITH THE LOAD WHILE AT ANY VOLTAGE.
6. Always use the GROUND HOOK to ground the cable(s) prior to disconnecting the output cable.
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THIS PAGE LEFT BLANK FOR APPLICATION NOTES
O P E R A T O R M A N U A L
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PERFORMING SPECIAL OPERATIONS
The following section contains information on the care and upkeep of your new VLF SERIES AC Hipot. There are some notes on troubleshooting and service, which will save much time and money over the life of the unit.
Meter Re-calibration The VLF SERIES of AC hipots uses precision metal film resistors for measurement and calibration of the voltmeter. The use of these resistors in both the high voltage tank and the metering circuits has minimized circuit drift due to aging and temperature. But, a potentiometer (R4) on the voltmeter PCB can be used to correct for movement changes from the aging of the meter.
The certification of meters on a yearly basis is recommended to ensure accurate test results.
Voltmeter Re-calibration 1. Locate the unit in a position that will allow easy reading of the meters.
2. Remove the panel screws and support the panel vertically to gain access to the calibration pot on the back of the voltmeter.
3. Zero the meter movement using the zero adjustment below the scale window.
4. Perform the steps in Setting up the Equipment at the start of SECTION 2. Be sure to ground the front panel to a solid earth ground using the supplied black ground test lead prior to connecting the unit to input power.
5. Connect the output cable to a calibrated reference meter with ability to read to the full output voltage of the unit. Be sure to ground the low side of the meter.
SECTION
3
O P E R A T O R M A N U A L
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6. Raise the output to one half scale on the unit meter. Adjust R4 as required.
7. Check calibration at both half and full scale. If the customer facility calibration certification requires more points of reference, follow those procedures instead of these.
Miscellaneous
Note: During normal operation, the control panel will heat due to the variable transformer output control. The heat exhibited is normal and does not affect the operation of the test set at all.
Oil Insulated High Voltage Tanks The oil-filled tanks in all the VLF SERIES of hipots are field serviceable. The only requirement is that the tank must be oil filled under vacuum at re-assembly. The parts to service the tank are available from HIGH VOLTAGE, INC. at the address noted on the inside front cover of this manual.
The oil level in the tank should be .50 - .75 inches from the lid when the oil temperature is 20C.
Packing the Cables The cables pack neatly into the side storage compartments. The interconnect and input line cord should be inserted together with the input cord coiled inside the interconnect. The output cable coils into the opposite side of these cables. With the output cable, the output limit resistor, and the output terminations will store without forcing anything into place. The shorting stick will slide into the same side with the output cable. Be sure to coil the ground braid neatly before doing this.
Saved 2/1/2001 7:19:00 AM, T:\DOCUMENTS\Manuals\VLF\archive\pl_vlf6022v.doc, Page 1 of 3
J1 1 CONNECTOR, INPUT POWER, 120V, 25A , 2 POLE 3-WIRE GROUNDING, ARROW-HART#5278C J2 1 CONNECTOR, BULKHEAD, 2 SOCKET, CINCH # S302AB J3 1 CONNECTOR, BULKHEAD, CIRCULAR, 11 PIN, AMPHENOL # 97-3102A-20-33S J4 1 PART OF HIGH VOLTAGE TANK (J2) J5 1 PART OF HIGH VOLTAGE TANK (J1) J6 1 CONNECTOR, BNC, AMPHENOL # UG-1094A/U
