Current Limit Control Specifications - Pacific UPC-32 Operation Manual

2.1.2.1 CSC (CONTINUOUS SELF CALIBRATION) SPECIFICATIONS
The UPC includes a user selectable "Continuous Self Calibration" function. When active, this function
maintains a constant output voltage amplitude at the metering sense point, comparing the metered
voltage at that point to the set value and correcting for any difference. Accurate calibration of the voltage
metering function is essential for CSC to operate accurately.
When INT SENSE is chosen, CSC attempts to precisely maintain accurate COMMAND (program)
voltage at the input side of the Output Relay of the power source.
To compensate for load voltage drops due to distribution losses, CSC can be effectively used to maintain
COMMAND (program) voltage very precisely at the load by selecting EXT sense with sense leads
connected at the load and having CSC enabled.
Basic properties of the CSC function are:
1. Voltage level held to ± 0.05% of the program voltage referenced to the internal voltmeter with
CSC enabled.
2. Response time varies anywhere from 1 ms. to 1 second and only responds while the UPC is
metering, not while in Program Edit or Setup mode.
3. CSC operates independently of selected waveform, does not increase distortion and is stable
into any PF load.
4. Automatically switches between internal and remote voltage sensing as the metering function is
switched between INT and EXT.
5. The CSC circuit does NOT function during transients.
6. CSC will only correct the Output Voltage by ± 10%. If the sense voltage is not within ± 10% of the
COMMAND voltage, CSC will become disabled until the Output Voltage is back within ± 10% of
the COMMAND voltage. Each phase operates independently.

2.1.3 CURRENT LIMIT CONTROL SPECIFICATIONS

Current limit is provided for all phases through a single RMS current value. The range of this value is
equal to the ammeter range, as set by the AMPS TO VOLTS RATIO (see section 2.2.2). This function is
an average responding, RMS-programmed function with a response time of approximately 100-200 mS.
Range:
Resolution:
Accuracy:
Amps to Volts ratio x 10 (divide by 3 for 3Φ power form)
(divide by 1.5 for single phase power sources containing 2 power amps).
Range/2000 (.05%)
±1% of full scale over the full range of ambient conditions
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SECTION 2 SPECIFICATIONS