Lincoln Electric POWER WAVE SVM156-A Service Manual page 88

F-42
NEGATIVE (-)
OUTPUT
TERMINAL
TEST PROCEDURE
1. Remove main input supply power to the
Power Wave 455/R.
2. Remove the case top and sides and perform
the Input Filter Capacitor Discharge pro-
cedure.
3. Using the 5/16" wrench, remove and insu-
late lead 202A from the negative output ter-
minal.
4. Remove any output load that may be con-
nected to the Power Wave 455/R.
5. With the analog ohmmeter, measure the
resistance between the positive and nega-
tive output terminals (NOT the STT termi-
nal). Refer to Figure F.15.
TROUBLESHOOTING & REPAIR
OUTPUT RECTIFIER TEST (CONTINUED)
FIGURE F.15 – OUTPUT RECTIFIER TEST
POWERWAVE 455/R
POWER WAVE 455/R
I ON
O OFF
STT OUTPUT
TERMINAL
POSITIVE (+)
OUTPUT
TERMINAL
IMPORTANT: The positive (+) meter probe
must be attached to the positive (+) output ter-
minal and the negative (-) meter probe must be
attached to the negative (-) output terminal.
6. If the reading is more than 200 ohms, the
output rectifier modules are not shorted. If
the reading is less than 200 ohms, one or
more of the rectifier modules are shorted.
Refer to the Output Rectifier Module
Replacement procedure.
7. Reconnect lead 202A to the negative output
terminal.
8. Replace the case top and sides.
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