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

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7.
Raise the output to one half scale on the unit meter. Adjust R4 as required.
8.
Check calibration at full scale and on the high range at both half and full scale. If the customer
facility calibration certification requires more points of reference, follow those procedures instead
of these.
9.
Calibration must then be verified with the panel in the horizontal operating position to check for
any meter balance affect on the calibration.
Current Meter Re-calibration
10.
Locate the unit in a position that will allow easy reading of the meters.
11.
Remove the current meter panel screws and support the panel vertically to gain access to the
calibration pot on the back of the current meter.
12.
Zero the meter movement using the zero adjustment below the scale window.
13.
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.
14.
Set the CURRENT RANGE to X1 position.
15.
Connect the output cable to a calibrated reference meter with ability to read 1mA ac. Use a
series resistance or capacitance to allow for precise resolution when calibrating. Be sure to
connect the low side of the reference current meter to LOAD RETURN and place the RETURN
MODE switch in GUARD position.
16.
Raise the output to one half scale on the unit meter. Adjust R4 as required.
17.
Check calibration at full scale. If the customer facility calibration certification requires more points
of reference, follow those procedures instead of these.
18.
Calibration must then be verified with the panel in the horizontal operating position to check for
any meter balance affect on the calibration.
19.
Check other ranges to verify accuracy. 1% range resistors should not require any adjustment on
higher ranges. The output current can only be run to full output current with a capacitive load.
Resistive loads are limited to about 1/2 rated current.