SECTION 5
TROUBLESHOOTING
20
F. SCR1 Troubleshooting (See Figure 5-1)
Resistance Checks
SCR1-A
SCR1-K
5 ohms
If reads open, then replace R1
SCR1-G
SCR1-K
diode forward drop
(low impedance using diode scale)
Gate Lead from Inverter Control should be disconnected
If reads short, then replace SCR-1
Voltage Checks
SCR1-G
SCR1-K
0 V dc
Torch switch deenergized
0.6 V dc
Torch switch energized - if missing, check Inverter Control