KEPCO MST Series - Manual (Page 42)

3-10
MST SERIES 061813
2. If the CURRENT MODE indicator is on, issue a command from the host computer to set the
UUT to Voltage mode. Verify that VOLTAGE MODE indicator is on.
3. Issue a command from the host computer to reset the UUT. This causes the UUT to be pro-
grammed to zero volts.
4. Connect the voltmeter to test connector J5, pins 1 (REF) and 6 (GND) (see Figure 2-4) and
verify meter reads between 5.00000V ± 500 µV volts. If meter reading is outside these limits,
adjust potentiometer R49 for reading of +5.00000V ± 50 µV.
3.8.3 OUTPUT VOLTAGE (E
O
) ZERO ADJUST (R11)
This procedure adjusts the offset of the voltage comparison amplifier to be zero for a pro-
grammed output voltage of zero.
1. Configure DC OUTPUT connector as shown in Figure 2-3 and close S1.
2. With the load disconnected, issue a command from the host computer to enable the output
(output relays closed). Verify OUTPUT ENABLED and VOLTAGE MODE indicators are on.
3. Connect DVM to DC output connector (see Figure 2-3) pin 5, Sense 1 (+) and pin 2, Sense 2
(–) and verify that output is 0V ± 500 µV.
4. If the measured output is outside these limits adjust potentiometer R11 for reading of
0.00000V ± 50 µV.
3.8.4 CURRENT SENSE ZERO ADJUST (R50)
This procedure adjusts the current sensing amplifier to zero with no current flowing through the
current sensing resistor.
1. Issue command from the host computer to reset the UUT.
2. Verify VOLTAGE MODE indicator is on.
3. Connect voltmeter to test connector J5, pins 4 (CSNS - Current Sense) and 6 (GND) and
verify meter reads 0.00000V ± 500 µV. If meter reading is outside these limits, adjust potenti-
ometer R50 for 0.00000V ± 50 µV.
3.8.5 OUTPUT CURRENT I
O
ZERO ADJUST (R51)
This procedure adjusts the offset of the current comparison amplifier to be zero for a pro-
grammed output current of zero.
1. Issue commands from the host computer to set the UUT to Current Mode, program output
current to 0.0A, voltage limit to E
MAX
and disable the output.
2. Verify CURRENT MODE indicator is on and OUTPUT ENABLED indicator is off.
3. Connect voltmeter to test connector J5, pins 4 (CSNS - Current Sense) and 6 (GND) and
verify voltmeter reads 0.0000V ± 500 µV. If voltmeter reading is outside these limits, adjust
potentiometer R51 for 0.0000V ± 100 µV.