Service manual

86 Repair Procedures Welch Allyn Propaq Encore Vital Signs Monitor
Replacing the SpO
2
Circuit Boards
This describes how to replace the two SpO
2
circuit boards in the SpO
2
module and in the
expansion module without a CO
2
option. To replace SpO
2
boards in an expansion module
with a CO
2
option, see “Replacing the MSP/SpO2 Circuit Boards” on page 87.
1. Open the SpO
2
module (“Opening the SpO2 Module” on page 85) or the expansion
module (“Opening the Expansion Module Rear Panel” on page 79).
2. Disconnect the cable(s) from the SpO
2
SCP board by carefully releasing the securing
clips and unplugging the connectors.
3. Disconnect the speaker cable from the SCP board.
4. Remove the speaker side panel from the chassis.
5. Remove the one or two screws securing the SCP board and SpO
2
board to the rear
panel.
6. Lift out the two circuit boards and patient connector side panel as a unit. (The side
panel easily slides out.)
7. Using equal pressure on both sides of the connector, disconnect the patient
connector side panel connector from the SpO
2
circuit board.
8. Disconnect the two circuit boards by gently pulling them apart.
When installing the SpO
2
circuit boards first, plug the two circuit boards together. Then:
• Connect the patient connector side panel connector to the SpO
2
circuit board.
• Set the two circuit boards and side panels in place, making sure that the boards
are seated on the support tabs.
• Torque screws to 4.75in-lbs to 5.25in-lbs (.54N-m to .59N-m).
• Reconnect the printer and expansion cables to the SCP board.
Caution When replacing the SpO
2
circuit boards, remove both circuit boards
with the patient connector side panel still connected. Attempting to disconnect
the patient connector side panel from the SpO
2
circuit board before removing
both circuit boards with the side panel can damage the flex-cable between the
side panel and the SpO
2
circuit board.
Caution In the next step, the connector securing clips are fragile and will break
if not handled carefully.