Troubleshooting & repair, Control board transformer (t3) test (continued), Warning – Lincoln Electric IDEALARC DC-655 User Manual
Page 73
F-31
F-31
IDEALARC DC-655
TROUBLESHOOTING & REPAIR
CONTROL BOARD TRANSFORMER (T3) TEST (continued)
TEST PROCEDURE
1.
Disconnect the main AC input power to the
DC-655 machine.
2.
Remove the case top and sides.
3.
Locate the control board transformer (T3)
mounted on the rear of the control box. See
Figure F.11.
4.
Locate the transformer (T3) primary leads
(#255 and $256). See Figure F.11 and the
Wiring Diagram. Also locate the secondary
leads (#281 and #282).
ELECTRIC SHOCK
can kill.
• Do not touch electrically hot parts.
5.
Apply the correct three-phase input power
to the DC-655 and turn the power switch
(SW1) to the ON position.
6.
Carefully check for 42 VAC at the secondary
leads (#281 to #282). If 42 VAC is present,
the control board transformer (T3) is good. If
42 VAC is missing or low, proceed to the
next step.
7.
Carefully check for 115 VAC at the primary
leads (#255 and #256). If the 115 VAC is
present but the secondary voltage (42 VAC)
is missing or low, the T3 transformer may be
faulty. Replace.
8.
If the 115 VAC is NOT present at the prima-
ry leads, check the associated switch (SW1)
and wiring. See the Wiring Diagram.
9.
Perform the Control Transformer (T2) Test.
FIGURE F.11 – CONTROL BOARD TRANSFORMER (T3) LEADS
PRIMARY LEADS
#255 AND #256
CONTROL BOARD
TRANSFORMER
(T3)
CONTROL
BOX
SECONDARY
LEADS #281
AND #282
WARNING