Nellcor N-180, Manual

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N-180 Pulse Oximeter Service Manual
6-6
4. Rotate top shield being careful of transformer wires that enter notch
near the back; slide tabs out and lift free.
Screw, 2 places
CPU top shield (23)
Notch
Transformer (74) & (75)
and bracket (73)
28018A/40
Figure 6-4: Removing the Top Shield
Transformer Removal and Replacement
To remove and replace the transformer (figure 6-5, which also illustrates AC
filter details) follow these steps:
1. Gain access to the transformer by following the instructions in this
section for gaining access to components.
2. Remove top shield following instructions in this section.
3. Disconnect connector on CPU PCB connector CN5 (item 5 in
illustration).
4. Disconnect connector on CPU PCB connector CN7 (item 4 in
illustration).
5. Remove two 6 mm hex nuts holding transformer to transformer bracket.
6. Remove transformer.
7. Inspect AC filter and determine if a ground strap (item 1 in illustration)
is soldered to the bottom ground lug of the filter.
8. If the AC filter lacks a ground wire, remove the filter and solder a
ground wire on the filter lug (a 2-inch length of wire is included in the
AC filter replacement kit). Follow the instructions for removing and
replacing the AC filter as given in this section.