Enabling And Disabling Compressors; Compressor Motor Protection; Compressor Circuit Breakers; Advanced Scroll Temperature Protection (Astp) - Carrier 38APS025 Manual

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ENABLING AND DISABLING COMPRESSORS —
Compressors in the 38AP units can be enabled or disabled in
the controls. To enable or disable a compressor, toggle the
value in the Configuration SERV menu for each individual
compressor.
COMPRESSOR MOTOR PROTECTION — Two types of
motor protection are used on the scroll compressors.
Compressor Circuit Breakers — Compressors have a man-
ual reset, calibrated trip, magnetic circuit breaker for overcur-
rent protection. Do not bypass connections or increase the size
of the circuit breaker to correct trouble. Determine the cause
and correct it before resetting the breaker.

Advanced Scroll Temperature Protection (ASTP)

non-digital Copeland compressors are equipped with advanced
scroll temperature protection (ASTP). A label located above
the terminal box identifies models that contain this technology.
See Fig. 158.
-30 -20 -10 0 10
Saturated Suction Temperature (°F)
Fig. 156 — Compressor Operating Envelope, °F
Saturated Suction Temperature (°C)
Fig. 157 — Compressor Operating Envelope, °C
— All
20 30 40 50 60
Fig. 158 — Advanced Scroll Temperature
Advanced scroll temperature protection is a form of internal
discharge temperature protection that unloads the scroll com-
pressor when the internal temperature reaches approximately
300 F (150 C). At this temperature, an internal bi-metal disk
valve opens and causes the scroll elements to separate, which
stops compression. Suction and discharge pressures balance
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a38-7307
Protection Label