TM 5-3805-280-24-1
Tests
HIGH AND LOW PRESSURE SWITCH TEST
SPECIFICATIONS
345 35 kPa (3.45 0.3 bar) (50
Low Pressure Switch (Normally
5 psi)
Open) Closes on Increasing
Pressure
173 35 kPa (1.73 0.3 bar) (25
Low Pressure Switch (Normally
53 psi)
Open) Opens on Decreasing
Pressure
2760 138 kPa (27.6 1.38 bar)
High Pressure Switch (Normally
(400 20 psi)
Closed) Opens on Increasing
Pressure
1310 138 kPa (13.11 1.38
High Pressure Switch (Normally
bar) (190 20 psi)
Closed) Closes on Decreasing
Pressure
SERVICE EQUIPMENT AND TOOLS
Volt-Ohm-Amp Meter
JT02051 3-Gauge Manifold w/Hose And Quick Coupler
NOTE: The line that attaches the high and low pressure
switch has a valve installed to prevent discharging
the air conditioning system when switch is
removed. The high pressure switch is normally
closed when removed from the machine. It does
not open when installed in the A/C system until
pressure exceeds specification.
1. Remove high and low pressure switch.
2. Connect a portable pressure source, such as a
hydraulic hand pump, to high and low pressure switch.
9031
3. Using an ohmmeter measure continuity between
25
terminals A and B until low pressure switch pressure
6
increases to switch closing pressure specification.
Low Pressure Switch (Normally Open)--Specification
Closes on Increasing Pressure ............ 345 35 kPa (3.45 0.3 bar) (50
5 psi)
Low Pressure Switch (Normally Open)--Specification
Opens on Decreasing Pressure ........... 173 35 kPa (1.73 0.3 bar) (25
53 psi)
Continued on next page
CED,TX14795,4346
1904MAR981/2
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