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35827_A
Remove the Phillips screws that retain the cover and then remove the cover. Locate the diode
assembly at the rear of the case as shown highlighted in Figure 9A. Remove the 11/32” nuts
that retain the transformer output leads to the heatsink assembly and then position these leads
so that they are at least 1/4 inch away from any objects near them. The diodes must be
disconnected for the test to be valid.
Connect your meter clips as shown in Figure 9A. For this direction of polarity attach the red
positive (
+
) lead to the upper diode and attach the black negative (
-
) lead to the center DC
output terminal. Set your meter to the ‘diode check’ position as shown in Figure 9B.
Figure 9A
Figure 9B
The value you see should vary between .450 and .600 volts DC due to the variations in diodes
and test meters. If this diode had failed shorted the meter would display “.000” or sound an
audible beep to indicate ‘continuity’ exactly as it does when you touch the test probes of your
meter together. If this diode had failed open, this meter would display a
flashing
“3.000”, other
meters would display “OL”. An open diode will measure ‘open’ exactly as it does when you do
not touch the test probes of your meter together.
