Lincoln Electric 11519 Service Manual page 98

F-52
MAIN TRANSFORMER AND OUTPUT CHOKE
REMOVAL AND REPLACEMENT (continued)
LEAD
X1
OUTPUT
CHOKE
POSITIVE
LEAD
MAIN
TRANSFORMER
PROCEDURE
1. Disconnect main input power to the machine.
2. Remove the case side panels using a 3/8 in.
nutdriver.
3. Test that the capacitors are discharged using a
volt ohmmeter. Polarity must be observed.
4. Remove lead X1 from the left side SCR heat
sink assembly using a 1/2 in. socket wrench,
extender and universal adapter.
F.17.
5. Remove lead X4 from the right side heat sink
assembly using a 1/2 in. socket wrench, exten-
der and universal adapter.
6. Remove the two transformer secondary leads
X2 and X3 (braided copper strap) from the neg-
ative capacitor bank buss bar using two 1/2 in.
open end wrenches.
TROUBLESHOOTING AND REPAIR
FIGURE F.17 — MAIN TRANSFORMER REMOVAL
LEADS
X2 AND X3
See Figure
Power MIG® 255XT
OUTPUT
CHOKE
LEAD
NOTE: PLUG-IN LEADS ARE
NOT SHOWN FOR
CLARITY.
LEAD
X4
POWER
ENHANCEMENT
CHOKE
7. Disconnect and label all transformer leads
from the reconnect panel using a 3/8 in. open
end wrench.
8. Disconnect and label all leads from the input
power switch.
9. Remove the power switch.
10. Disconnect thermostat leads #320 and #320B
from the SCR Rectifier.
F-52