Verification Of The Secondary Diode (D2, D3); Verification Of The Primary Igbt (Q1A-Q4C) - Thermal Arc ARCMASTER 200 S Service Manual

11
200S ADVANCED TROUBLESHOOTING
5.5 Verification of the secondary
Diode (D2, D3)
CAUTION
Before performing any portion of the procedure
below, make certain the unit is placed in the initial
set up condition as described in section 11.4.1
"Preparation" on page 11-6.
1) Verify the characteristic of the secondary
diode, D2 and D3, using a diode tester.
2) Refer to Table 11-5 and Figure 11-14 for
the checkpoints on D2 and D3.
COMPONENT
TESTED
Diode 1 of D2,
and D3,
Diode 2 of D2,
and D3,
Table 11-5: Tester checkpoints for D2 and D3
Cathode
Figure 11-14: Tester checkpoints for D2 and D3
TERMINALS
ACCEPTABLE
Positive Negative
VALUE
lead lead
Anode Cathode 0.2 to 0.3V
Cathode Anode Open
Anode Cathode 0.2 to 0.3V
Cathode Anode Open
Cathode
Anode
Anode
5.6 Verification of the primary
IGBT (Q1A-Q4C)
CAUTION
Before performing any portion of the procedure
below, make certain the unit is placed in the initial
set up condition as described in section 11.4.1
"Preparation" on page 11-6.
1) Check whether there are any abnormalities on
the appearance of PCB6 and PCB7.
2) Verify the characteristic of the primary IGBT
(Q1A-Q4C), using a diode tester.
3) Refer to Table 11-6 and Figure 11-15 for
the checkpoints on PCB6 and PCB7.
COMPONENT
TESTED
Collector-Emitter
of Q1A~Q2C with
PCB6
Collector-Emitter
of Q3A~Q4C with
PCB7
Table 11-6: Tester checkpoints for Q1A-Q4C
E C
E C
E C
E C
Figure 11-15: Tester checkpoints for Q1A-Q4C
11 – 11
TERMINALS
ACCEPTABLE
Positive Negative
VALUE
lead lead
C CE Open
CE C 0.2 to 0.5V
CE E Open
E CE 0.2 to 0.5V
PCB6
E C
E C
E C
E C
E C
PCB7
E C
E C
E C