P- 2.0.3 Isolate 'Switched' 24 V-B - Fresenius Medical Care 2008K2 Troubleshooting Manual

P- 2.0.3 ISOLATE 'SWITCHED' 24 V-B

IMPORTANT! TURN THE MACHINE OFF!
a)
b) Figure below, locate the motherboard's nine (9) pin TEST connector.
Figure 129 – Card Cage / TEST Connector / 24V-B
c) TIGHTLY HOLD the red meter lead on the TEST connector's pin 8 (2
d) Looking for approximately 24.0 volts to momentarily pulse on and off more than once,
LOOKING AWAY FROM THE METER
(30) seconds!
e) FOUR (4) possible scenarios 1) or 2) or 3) or 4) below:
IF (and ONLY if) momentarily went to between 23.0 and 28.0 volts but after
1)
about thirty (30) seconds dropped to AND remained less than 3.0 volts:
procedure number
IF (and ONLY if) ALWAYS less than 3.0 volts i.e. NEVER more than 23.0 volts!
2)
Perform procedure number P- 2.0.3 once again just to be sure. If still always less than 3.0 volts,
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proceed to
Scenario #3 and #4 next page
, turn the machine ON (fan running) and watch for thirty
P- 2.0.4 (page 642).
, procedure number P-
2008K/K2 Troubleshooting Guide
P/N 507298 Rev. H
nd
pin from the right).
2.0.5.
WITHOUT
See
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