Welch Allyn Spot Vital Signs 4400, Service Manual

Page: 36 / 132

CAUTION
To avoid mismatching screws and holes, keep the screws for each
piece with that piece as you remove modules and circuit assemblies. It is possible
to mistakenly install machine screws in locations intended for plastite screws.
Plastite screws have a Torx-pan head.
Required tools and equipment
• Phillips #0 screwdriver
• Phillips #1 screwdriver
• T-10 Torx screwdriver
• 3/8" socket
Torque value table
Use this table to determine how much torque to apply to screws by type and location when
reassembling the device.
Description Torque specification Bit type Where used
NUT, 5/16-32. THIN PROFILE 3.0 +/-0.5 in-lbs 3/8" hex Power harness
SCR,4-20X.31 PLASTITE PH TORX 4.5 +/-0.5 in-lbs T-10 Torx SpO2 insert - Rear housing
SCR,4-20X.31 PLASTITE PH TORX 4.5 +/-0.5 in-lbs T-10 Torx Pneumatic & Sensor assy
SCREW 4-40 .250 PAN PHILLIPS
STEEL ZINC
4.5 +/-0.5 in-lbs #0 Phillips SpO2 sensor & SpO2 adapter
PCBA
SCREW, M4 X 10 PAN HEAD W
NYLOC
7.5 +/-0.5 in-lbs #1 Phillips Rear - Front housings
SCR, M4 PAN HD, PHD,
SHOULDER
4.5 +/-0.5 in-lbs #1 Phillips Battery Door
SCR, 4-20X.31 PLASTITE PH TORX 4.5 +/-0.5 in-lbs T-10 Torx Pneumatic & Sensor assy
SCREW, M4 X 10 PAN HEAD W
NYLOC
7.5 +/-0.5 in-lbs #1 Phillips Rear and Front housings
Connector types
Disassembly and repair procedures require that you disconnect and reconnect the following
connector types inside the device:
•
Locking (squeeze-release)
: Locking connectors use a latching mechanism to prevent
accidental disconnection during assembly and use. The latch is located on one end of a tab so
it may flex and lock into place when coupled with its matching connector. The tab provides a
lever to release the latch. Some connectors have multiple latches that require you to press
multiple tabs to release.
32 Disassembly and repair