Verification Of The Power Input Circuitry; Verification Of The Ac Input Voltage Using An Ac Voltmeter - Thermal Arc 160 TS ARCMASTER Service Manual

ARCMASTER 160TS
11.05 Verification of the Power Input Circuitry
Before performing any portion of the procedure below, make certain the unit is placed in the
initial set up condition as described in section 11.04.1 "Preparation"
1. Verification of the AC input voltage using an AC voltmeter.
a) Verify input voltage (Phase-to Phase) using an AC voltmeter. (The capability of the voltmeter
should be more than 600VAC). Measure the point between lines U1 and V1 on the input
switch, S1. The location of points U1 and V1 on switch S1 are indicated in Figure 11-7.
b) If the input voltage is out of the operating range of the unit, which is ± 10% (187 ~ 253VAC) of
the rated voltage (208-230V), verify the available power capacity at the installed site. If the
input voltage is within the operating range, recheck the input voltage while welding, as welding
may cause the input voltage to decrease to a value below the operating range of the unit.
c) Verify input voltage after the input switch (S1) using an AC voltmeter. (The capability of the
voltmeter should be more than 600VAC.)
Using an AC voltmeter, measure between the points U2 and V2 on the input switch, S1.
The location of points U2 and V2 on switch S1 are indicated in Figure 11-7.
d) If this voltage is out of the operating range, which is ± 10% (187 ~ 253VAC) of the rated
voltage (208-230), replace S1 following the process in section 12.3.14.
e) Verify the rectified output voltage of the primary diode, D1 using a DC voltmeter. (The
capability of the voltmeter should be more than 400VDC.) Using a DC voltmeter, measure
between the points "+" [+] and "-" [-] on D1. Points "+" and "-" are on PCB1 (WK-5466). See
Figure 11-8. The measured voltage should be approximately 1.4 times larger than input voltage
CAUTION
Figure 11-7: Check points U1, U2, V1 and V2
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