Carrier TRANSICOLD 69NT20-274 Operation And Service page 25

to 1.3 Amps. The valve remains 100% open below 0.2 A
and is 0% open at 1.3 A.
Code 02 --- Quench Valve (Open or Closed)
Some Models have a thermostatic expansion
quench
APPLICABLE. To see which Models have a
solenoid quench valve refer to Section 5.
Modulating controllers shall also operate a Quench
solenoid valve (QV) to supply a minimum flow of
refrigerant to the compressor suction inlet to assure the
required motor cooling and maintain the compressor
discharge temperature below a maximum value.
The quench valve is opened whenever the suction
solenoid valve is closed and the suction modulation valve
is less than 40% open. If the suction modulation valve is
more than 60% open or the suction solenoid valve is
open, the quench valve is closed.
Code 03 --- Suction Solenoid Valve (Open or Closed)
Model (69NT40) will have a suction solenoid valve
(SSV) to provide maximum refrigerant flow to the
refrigeration system. This valve will always be open for
set points below
temperature pulldown periods unless current limiting
restricts its use.
Codes 04, 05 & 06 --- Line Current, Phase A, B & C
The container is supplied by a three-phase electrical
system, so there are three current sensors in the system.
The current draw is used for control and diagnostic
purposes.
For control processing, the largest of the three
current values is used for current limiting purposes.
For diagnostic processing, the current draws are used
to determine control unit operations. Whenever a heater
or a motor is turned ON or OFF, the current draw
increase/reduction for that activity is measured for all
three legs of the system. Each current draw is then tested
to determine if it falls within the expected range of values
for the respective unit. Failure of this test will result in a
pre-trip failure or a control alarm indication.
Code 07 --- Supply Voltage
The supply voltage will be a nominal 230 vac or 460
vac level, and will determine which set of current draw
values to use for testing. The voltage is constantly
monitored and a voltage level --- lower than 20% of its
proper voltage will result in "LO" being alternately
displayed with the set point.
Code 08 --- Supply Frequency
The value of the main power frequency is displayed
in Hertz.
Code 09 --- Ambient Air Temperature
The ambient sensor (AMBS) measures the
temperature outside the container. It is a factor in
determining which speed the condenser fans will use
(optional), and it is also used as a diagnostic factor for
determining the system load. For locations of sensor, see
Figure 1-3.
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NOTE
valve, so Code 02
---10_C (+14_F) and during
search engine
Code 10 --- Compressor Suction Temperature
Measured just prior to the compressor suction
service valve, the compressor suction temperature is used
for pre-trip diagnostics as an indicator of proper quench
operation. For location of compressor suction sensor
(CPSS), see Figure 1-3.
is NOT
Code 11 --- Compressor Discharge Temperature
The compressor discharge temperature is measured
near the compressor discharge valve. For location of
compressor discharge sensor (CPDS), see Figure 1-3.
Code 12 --- Saturated Condenser Temperature
The saturated condenser temperature is measured
on a condenser return bend. It is also used to calculate
discharge pressure. For location of condenser saturation
sensor (CSAS), see Figure 1-3.
Code 13 --- Compressor Discharge Pressure
Calculated
temperature.
Pressure is displayed in units of psig when code 27 is
set to _F and units of bars when code 27 is set to _C. "P"
appears after the value to indicate psig and "b" appears
after the value to indicate bars.
Code 14 & 15 --- Future Expansion
These codes are for future expansion.
Code 16 --- Compressor Motor Hour Meter
Records total hours of compressor run time. For
software revision number 106 or greater, records total
hours in increments of (10) ten hours (ie. 3000 hours
displayed as 300).
Code 17 --- Hours Since Last Trip Start
This is the total number of hours since the last trip
start. Up to 62 days can be recorded. A back-up battery
keeps the clock running when power is disconnected.
Code 18 --- Software Revision Number
The software revision number is displayed.
Code 19 --- Serial # (First 4 of 8)
The first 4 digits of the Serial number for the
Microprocessor are displayed.
Code 20 --- Serial # (Second 4 of 8)
The last 4 digits of the Serial number for the
Microprocessor are displayed.
Code 21 --- USDA #1 Probe Temperature
Displays the temperature of the #1 remote cold
treatment probe.
Code 22 --- USDA #2 Probe Temperature
Displays the temperature of the #2 remote cold
treatment probe.
1-17
(not applicable for some units)
(not applicable for some units)
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from the saturated
(not applicable for some units)
(not applicable for some units)
(not applicable for some units)
(not applicable for some units)
(not applicable for some units)
condenser