Heater Relay- 2.0.0 Isolate Diode 17 (D17) - Fresenius Medical Care 2008K2 Troubleshooting Manual

HEATER RELAY- 2.0.0 ISOLATE DIODE 17 (D17)

A bad diode 17 (D17) destroys Power Logic Boards. See parts a THROUGH h below:
a) Turn the power off and unplug the machine!
b) Per Figure 111 below, open the power supply to see the component side of the Power Control board.
IMPORTANT!
c) The twenty (20) and nine (9) pin* cables MUST be unplugged! *BEFORE unplugging
the nine pin cable NOTE its polarity (i.e. orange wire on the right)!
Figure 111 – Power Control Board (Diode 17)
IMPORTANT! Set your volt meter to
d)
RESISTANCE (Ω)!
g) Per Figure 111, check diode 17 (D17) by placing one
meter lead on one side of it and the other lead on the
other side.
h) Figure right, reading the meter's numeric AND units display,
TWO (2) possible scenarios:
IF (and ONLY if) between 900 and 1500 Ω! (0.900 and 1.5 KΩ):
1)
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Proceed to
2) IF less than 900 Ω (0.900 KΩ) OR more than 1500 Ω (1.5 KΩ):
Perform parts a THROUGH e below:
IMPORTANT!
a)
good! To LOCATE the Power Logic board refer to
Parts b through e next page
Caution!
, procedure number
BOTH
Replace the Power Control AND Power Logic boards with known
2008K/K2 Troubleshooting Guide
P/N 507298 Rev. H
Electrocution hazard if not unplugged!
HEATER RELAY- 2.0.1
Figure 4A (page 9).
Diode 17 is good!
.
Diode 17 is bad!
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