B&K Precision 1620A-1623A - Manual - Manual (Page 14)

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7.3. VOLTAGE CALIBRATION
1. Connect the multimeter to measure the DC voltage across the
power supply (+) and (–) output terminals.
2. Turn on the power supply, and turn the panel VOLTAGE
adjustment knob fully clockwise (maximum output).
3. Adjust trimmer VR11 for a reading (Vmax. +0.5) ±0.1 volts
on the multimeter. Vmax is the maximum normal output of
the specific model under calibration.
7.4. VOLTAGE ALIGNMENT
1. Set the output voltage to about half the maximum allowable
output for respective model.
2. Align the voltmeter reading with the multimeter reading.
For BK Precision Analog series, adjust the trimmer VR-6 on
the main PCB.
For BK Precision Digital series, adjust the trimmer VR-1 on
the back of meter PCB.
7.5. CURRENT CALIBRATION
1. Connect the 0 – 50ohm / 250W resistive load in series with
the multimeter to measure the DC output current terminals.
2. Adjust trimmer VR-5 fully anti-clockwise (referring to the
component side).
3. Adjust the output voltage to the maximum allowable
output for respective model.
4. Adjust the variable resistive load to obtain (Imax +0.1)
±0.02 Ampere on the multimeter. Imax is the maximum
nominal allowable output current of resistive model.
5. Adjust trimmer VR-5 clockwise slowly until the limiting
point is just reached and the C.C. LED lights up at the
same time.
7.6. AMMETER ALIGNMENT
1. Adjust the output voltage to half of its maximum allowable
output voltage for respective model.
2. Adjust the variable resistive load to obtain half of its
maximum allowable current for respective model.
3. Align the ammeter reading with the multimeter reading.
For BK Precision Analog series, adjust the trimmer VR-7
on the main PCB.
For BK Precision Digital series, adjust the trimmer VR-2
on the back of meter PCB.