Pacific Power Source UPC-32, Руководство по эксплуатации

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SECTION 4 OPERATION
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4.6.3.1.1.1 PROGRAMMABLE OUTPUT IMPEDANCE CALIBRATION MENU
Press EDIT again, while the PROG. Zo menu is displayed to access the Prog Zo Calibration screens to enter
calibration values for the Prog Zo function.
NOTE: Each power source is pre-calibrated at the factory, but if the system configuration changes, re-
calibration of this function is desired, or if the RAM (memory) in the UPC has been lost or erased, use this
screen to enter new calibration values. The calibration procedure is listed below.
The Z direct and Z xfmr values calibrated at the factory are compensated for the power source impedance at
the output terminal of the power source. To compensate for additional wiring, fixtures, magnetics, etc.,
follow the calibration procedure and include the external devices in the measurements.
Ф
Z direct XFMR ratio Z xfmr
1 0.006 | 1.50 0.450
2 0.032 | 2.00 1.400
3 0.016 | 2.50 2.970 RESET
Ф
column: Indicates the Power Form of operation (1, 2 or 3 phase).
Z direct column: Accepts the Direct-coupled impedance of the power source (per phase) for each
Power Form listed on the far left. During DIRECT coupled operation, the proper Z
direct value is used to calibrate the PROG Zo function based upon the Power Form
selected in the Program being executed.
XFMR ratio column: Accepts up to 3 separate XFMR ratios. Typically only one will be entered.
Z xfmr column: Accepts the impedances of the XFMR listed in the XFMR ratio column. During
XFMR coupled operation, the proper Z xfmr value is used to calibrate the PROG
Zo function based upon the XFMR ratio selected in the Program being executed.
RESET: Restores system default values to all PROG Zo calibration entries
To reset Prog.Zo calibration values, press ENTER to position the cursor over RESET then EXECUTE .
WARNING: RECALIBRATION REQUIRED
PRESS "EXECUTE" TO RESET PROG Zo CAL
PRESS "CLEAR" TO CANCEL
Calibration values for Direct-Coupled (Z direct) operation may be established via the following procedure.

Turn CSC OFF. Disable PROG. Zo. Execute a program in Direct coupled mode.

Establish the difference in output voltage between no-load and full-load voltage.

Divide the voltage difference by the full-load current. The result is the direct- coupled impedance.

Use the result to enter in as Z-Direct for the power form used to perform this test.
Z =
V_no_load - V_full_load
I_full_load
Calibration values for XFMR-coupled (Z xfmr) output may be determined in the same manner, except the Z
direct value must be subtracted from the Z xfmr calculation prior to entering the Z XFMR value into the UPC.
A reasonable approximation of transformer impedance can be estimated by measuring the DC resistance of
each XFMR secondary tap. That value may be entered for Z XFMR as an alternative to using the above
procedure for measuring actual XFMR impedance.
NOTE: XFMR impedances may vary greatly with temperature and frequency of operation.