High Voltage PFT Series, Safety, Operation, And Procedure Instructions

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12
PERFORMING SPECIAL OPERATIONS
The following section contains information on the care and upkeep of your new PFT SERIES Power
Frequency AC Test Set. 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 PFT SERIES of hipots use 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. Adjustment of potentiometer (R4) on the voltmeter and current
meter 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.
Set the VOLTMETER RANGE to LOW position.
6.
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