ESAB EPP-400 Manuel D'instructions page 304

section 6
three leads
6.4.4 procedure for verifying calibration of digital meters.
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 (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%.
clear insulation
two leads
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troubleshootinG
• 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.