Troubleshooting & repair, Main transformer removal & replacement (continued) – Lincoln Electric IDEALARC R3R-500 User Manual
Page 90
TROUBLESHOOTING & REPAIR
F-56
F-56
IDEALARC R3R
FIGURE F.34 – CHOKE REMOVAL
CHOKE
BOTTOM
"E" IRON
GLASTIC
STIFFENERS
THRU-BOLTS
(4)
MAIN TRANSFORMER REMOVAL & REPLACEMENT (continued)
REMOVAL OF CHOKE AND TOP
IRON ASSEMBLY
1. Remove the two (left and right) glastic stiffen-
ers connecting the negative rectifier plate
and choke assembly to the main transformer
thru-bolts. See Figure F.34.
2. Remove the top choke lead from the polarity
selector switch or the negative output termi-
nal.
3. Remove the bottom choke lead from the neg-
ative rectifier plate.
4. Label and cut the choke thermostat leads.
5. Using the 9/16” deep well socket wrench,
remove the four thru-bolts that clamp the top
“E” iron and choke assembly to the bottom
“E” iron. NOTE: for easier reassembly, clean
the threads.
6. Using a hoist, carefully lift the choke and top
iron assembly out and clear of the trans-
former coils.
NOTE: The coils may be “stuck” to the top iron
and may require some careful prying to
dislodge them. Depending upon which
coil(s) are to be replaced, it may be
advantageous to remove some of the
“stuck” coils with the top iron.
7. The leads from the coils that are to be
removed and/or replaced must be discon-
nected. See the Wiring Diagram.
When aluminum leads are re-connected, apply a
thin layer of Dow Corning 340 Heat Sink
Compound to mating surfaces.