Procedure For Verifying Calibration Of Digital Meters - ESAB ESP-400C Installation, Operation And Maintenance Manual

SECTION 6
Three Leads

6.4.4 Procedure For Verifying Calibration Of Digital Meters.

Clear Insulation
Two Leads
ESP 400C and 600C Plasma Power Sources
•
It is important to have the barrels of the black
and clear insulated wires, from the three lead
cable, be pointing in opposite directions.
•
The third wire attaches to the bus bar on the left
with the shunt mounting hardware. Orientation
of this wire is not critical.
Voltmeter
1. Connect a digital meter known to be calibrated
to the positive and negative output bus bars.
2. Compare the power source voltmeter reading to
the calibrated meter reading. Readings should
match within ± 0.75%
Ammeter
1. External to the power source, connect a
precision shunt in series with the work lead(s).
The best shunt is one with a value of 100 µΩ
(50mV/500A or 100mV/1000A) and a calibrated
tolerance of ± 0.25%.
2. Use a calibrated 4 ½ digit meter to measure the
output of the shunt. The amperage indicated
with the external shunt and meter should match
power source ammeter to within ± 0.75%.
Troubleshooting
6-19