Ametek CSW5550 User Manual page 114

User Manual
5.3.5 External Gain Control (RPV)
The External Gain Control is also referred to as the RPV function. This function takes a 0 to 7.07 VDC
input signal to adjust the output voltage from 0 to a full-scale output voltage, 156 or 312 Vrms. The
output waveform is programmed by the internal signal generator. Follow the steps in Paragraph 6.3.4 as
described below. The RPV input is applied to the same connector pins as described for the External
Signal input in Paragraph 6.3.4.These connections are repeated below. The connections are made
through a 16-pin, D-Sub connector, J32 on the rear panel of the power source. Refer to Table 6-2 for the
connector pin connections. The A, B and C inputs will be tied together for the same input signal.
1. Connect the external AC signal to the A, B and C inputs. Use pin 10 for the common
connection.
2. Program the ALC OFF and the High Voltage range. Do not close the output relays.
3. Press the MENU key to select UTILITY then VOLT/CURR CONTROL. Program VOLT REF to
RPV.
4. Again press the MENU key to select EXTERNAL CALIBRATION. This screen will show four
values to be calibrated:
a) The ZERO DC must have the value 0 entered with the output relays open. This value must
be entered even though it already shows the zero value. Perform this operation for all three
phases. This calibration must also be repeated for the RPV mode of operation.
b) FS OUT is the nominal output calibration value. This value must be between 0 and 4095.
Start with a value of 1000. Close the output relays with the ALC OFF. Apply and External
Input signal of 5.000 ± 0.005 volts. If necessary adjust the FS OUT value for an output of
62.4 times the exact value of the input signal. Repeat this calibration for all three phases.
This procedure must also be repeated for the RPV mode but the exact same value may be
programmed for the respective phase.
c) ZERO RMS This value is not used for the CSW.
d) FS ADC is the Full-scale calibration value. Turn OFF the ALC. Apply an External Input of
7.070 VDC ± 0.005 volts. Select the phase for calibration. Enter the value of 312.0 or 62.5
times the External input if it isn't exactly 7.070 volts. Repeat for all phases.
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California Instruments
CSW Series