Nellcor N-180, Manual

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N-180 Pulse Oximeter Service Manual
6-8
b. Connect blue wires to CPU PCB connector CN5 (item 5 in the
illustration).
c. Connect yellow wires to CPU PCB connector CN7 (item 4 in the
illustration).
11. Position AC filter ground-wire on the rear-most transformer bracket
stud (item 1 in the illustration).
12. If there is a green and yellow wire (item 3 in the illustration) on the
replacement transformer position the corresponding lug on the front
transformer bracket stud.
13. Fasten wire leads 1 and 3 to transformer bracket studs using two 6
millimeter hex nuts.
AC Filter Removal and Replacement
The AC filter is part of the AC inlet and control assembly. To remove and
replace the AC filter:
1. Gain access to the AC filter by following the instructions in this section
for gaining access to components.
2. To remove AC inlet assembly (that includes AC filter):
a. Remove screw holding AC inlet assembly to right side member of
the rear panel assembly.
b. If required, remove 6 mm hex nut on the rear most transformer
bracket stud (some monitors do not have a ground wire from the AC
inlet assembly to the transformer stud).
c. Lift out left side of rear panel assembly and attached AC power
inlet and control assembly (they are attached with a single screw).
3. Inspect replacement AC inlet filter for a ground wire on the bottom
ground lug. If a ground wire is not soldered to the lug, solder a ground
wire to the lug (a 2-inch length of wire is included in the replacement
kit).
4. Position AC filter ground-wire on the rear-most transformer bracket
stud (item 1 in the illustration) while simultaneously sliding AC inlet
filter into position on the bottom assembly.
5. Fasten right side member of rear panel assembly to AC inlet and control
assembly.
Battery Fuse
The battery fuse is in a fuse holder that is soldered to the CPU PCB. Once
you remove the top shield you can see the fuse beneath the connector that
routes between the CPU PCB and the oximetry module. To replace the fuse:
1. Disconnect the battery wire connector that connects to CN4 on the CPU
PCB.
2. Disconnect the ribbon cable between the CPU PCB and the oximetry
module.
3. Use a small flat blade screwdriver to gently pry the fuse from the holder.