Diagnostics; Electrical Requirements; Operating Characteristics - Carrier 30GTN Product Data

2. Safeties:
a. Unit shall be equipped with thermistors and all
necessary components in conjunction with the
control system to provide the unit with the
following protections:
1) Loss of refrigerant charge protection.
2) Low fluid flow detection.
3) Low chilled fluid temperature protection.
4) Low and high superheat protection.
5) Low control voltage (to unit) protection.
6) High-pressure switch.
7) Low oil protection for each compressor circuit
8) Ground current compressor protection.
b. Compressors shall be equipped with the following
manual-reset type protections:
1) Pressure overload.
2) Electrical overload through the use of definite-
purpose contactors and calibrated, ambient
compensated, magnetic trip circuit breakers.
Circuit breakers shall open all 3 phases in the
event of an overload in any one phase (single-
phasing condition).
c. Fan motors shall have inherent overcurrent
protection.

3. Diagnostics:

a. The diagnostic display module shall be capable
of indicating the safety lockout condition by
displaying a code for which an explanation may
be scrolled at the display. Information included
for display shall be:
1) Compressor lockout.
2) Loss of charge.
3) Low fluid flow.
4) Low oil pressure.
5) Cooler freeze protection.
6) High or low suction superheat.
7) Thermistor malfunction.
8) Entering and leaving-fluid temperature.
9) Evaporator and condenser pressure.
10) Electronic expansion valve positions.
11) All set points.
12) Time of day.
b. Display module, in conjunction with the
microprocessor, must also be capable of
displaying the output (results) of a service test.
Service test shall verify operation of every
switch, thermistor, fan, and compressor before
chiller is started.
I. Operating Characteristics:
1. Unit shall be capable of starting and running fully
loaded at outdoor ambient temperatures from 0° F
to 125 F (–18 to 52 C), without special controls.
2. Unit shall be capable of starting up with 95 F (35
C) entering-fluid temperature to the cooler.
3. Multi-step cooling capacity control shall be
accomplished through the use of unloaders and
compressor staging.
4. Two refrigerant circuits shall be provided to
protect against loss of total capacity.
5. Unit shall have automatic lead/lag feature to
automatically alternate the lead circuit to ensure
even compressor wear.
J. Motors:
1. Compressor motors shall be cooled by suction gas
passing around motor windings.
2. Condenser-fan motors shall be 3-phase type with
permanently lubricated bearings and Class B
insulation.
3. Fan motors are totally enclosed, air-over (TEAO)
type in accordance with IP-55.
K. Electrical Requirements:
1. Unit primary electrical power supply (3-phase)
shall be connected to a single location.
2. Unit control power (single-phase) shall be
connected to a separate entry point.
3. Unit shall be shipped with factory control and
power wiring installed.
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