KEPCO BOP 5-20DL, Operator'S Manual

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BOP 5-20DL 081915
4-5
4.2.7 CURRENT CHANNEL ZERO ADJUSTMENT (A1R83)
1. At rear panel, apply positive voltage between pins 2 and 3 (return) of the OUTPUT ON-OFF
port (2, Figure 2-2) to enable (turn on) the output. Refer to Table 1-7 for signal requirements.
2. With the unit turned off, connect a precision current measuring shunt, rated for the unit's
nominal output current (20A for BOP 5-20DL) to the output.
3. Connect DVM to the shunt's sensing terminals.
4. Set MODE switch to CURRENT and CURRENT CONTROL switch to OFF.
5. Place a short circuit across the front panel CURRENT PROGRAMMING INPUT terminals.
6. Locate the Io COMP AMP ZERO control (see Figure 4-2, A1R83), then turn on BOP and
adjust control for 0A ±(0.005% of I
O
nom), as read on DVM. For BOP 5-20DL, I
O
nom is 20A
and the adjustment range is ±1mA.
4.2.8 CALIBRATION OF I
O
FULL SCALE OUTPUT CURRENT (A3R316) AND FRONT PANEL
AMMETER (A7AR3B)
1. Turn BOP off and remove the cover (see Figure 4-2).
2. Connect either a precision ammeter or a precision current-measuring shunt resistor to the
output of the power supply. If a shunt is used, connect a DVM to the shunt’s sensing termi-
nals.
3. At the rear panel, apply a positive voltage between pins 2 and 3 of the OUTPUT ON-OFF
port (2, Figure 2-2) to turn the output ON (refer to Table 1-7 for detailed signal requirements).
4. Set BOP MODE switch (6, Figure 2-1) to CURRENT mode operation.
5. Set BOP CURRENT control (8) switch to OFF.
6. Using the CURRENT PROGRAMMING INPUT terminals (11, Figure 2-1), program the unit
by using an accurate and precise DC voltage source. Set DC programming source to +10V
±0.1mV for full scale output current.
7. Turn BOP power supply on.
8. Adjust A3R316 (see Figure 4-2 for location) until current reading displayed by ammeter or by
the shunt’s DVM exactly matches the BOP rated output current with 0.005% tolerance (-20A
±1mA for BOP 5-20DL). The current reading will show negative polarity due to the default
inverting configuration of the unit.
9. Adjust A7R3B until the front panel digital ammeter shows -20.0 Amperes.