Controls Test - Carrier PIC 5+ User Manual

Then Protective Limit Alarm evaporator freeze will be
displayed, the unit will shut down, if chiller is in recycle mode
then it will transition to TRIPOUT, and the CHILLED
WATER PUMP will remain on. The alarm will be clearable
when evaporator saturated refrigerant temperature,
evaporator refrigerant temperature, Leaving chilled water
temperature and entering chilled water temperature rise 5^F
(2.8^C) above the EVAP REFRIG TRIPPOINT.
Condenser Pump Control
The chiller will monitor the condenser pressure and may turn
on the condenser pump
If the condenser pressure is greater than or equal to the
COND PRESS OVERRIDE, and the entering condenser
water temperature is less than 115 ° F (46.1 ° C), the
condenser pump will energize to try to decrease the pressure
and alert 157 will be generated. The pump will turn off when
the condenser pressure is 3.5 psi (24.1 kPa) less than the
pressure override and the condenser refrigerant temperature)
is less than or equal to the entering condenser water
temperature plus 3^ F (1.7^ C).
NOTE: COND PRESS OVERRIDE is found in the
CONFIGURATION MENU/ PROTECTIVE LIMIT
CONFIG screen. The default value is 140 psig (965 kPa)
for 185PSI condenser and 250 psig (1724 kPa) for 300PSI
condenser; default value is 10 psig (137.9kPa) for 44PSI
condenser and 55 psig (379.2 kPa) for 72PSI condenser.
Condenser Freeze Prevention — This control helps prevent
condenser tube freeze-up by energizing the condenser pump
relay. The 19 Series PIC 5+ controls the pump and, by starting
it, helps to prevent the water in the condenser from freezing.
When the chiller is off and condenser saturated refrigerant
temperature is less than or equal to the condenser freeze
point, the condenser water pump will be energized (Alarm
State 262, PROTECTIVE LIMIT - CONDENSER
FREEZE). The fault state will clear and the pump will turn
off when the condenser saturated refrigerant temperature is
more than 5^ F (2.7^ C) above the condenser freeze point
and the entering condenser water temperature is greater than
the condenser freeze point. If the chiller is in recycle
shutdown Mode when the condition occurs, the controls will
transition to a non-recycle shutdown.
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5.19 - Controls Test

This function is used to test all controlled outputs except
compressor output. The test function will only be allowed to
run when the unit is Off.
User password is required to active this test function. All
control test parameters shall be accessible in the table
"QCK_TEST" . To perform the control test function, the first
item "Quick Test Enable" in the "QCK_TST" table shall be
set to enable. The "Quick Test Enable" item will be
automatically disabled in one hour in order to make the
controls go back to normal if someone forget to disable it.
Unless otherwise noted, all protective limits shall remain
active during Controls Test.
5.19.1 - Discrete Outputs
When control test is enabled, the following discrete outputs
can be enabled to be forced to ON by setting the according
points to Yes in the quick test table.
Guide Vane Increase, Guide Vane Decrease, Oil Pump Relay,
Oil Heater Relay, EC Valve Open, EC Valve Close,
Economizer Damper Valve Open, Economizer Damper Valve
Close, Alarm relay, Alert relay and Refrigerant Pump relay.
NOTE: the following outputs cannot be force to ON at the
same time
Guide Vane Increase and Guide Vane Decrease;
EC Valve Open and EC Valve Close;
Economizer Damper Valve Open and Economizer Damper
Valve Close
For oil pressure, a value >= 18 psi within 40 seconds after oil
pump is turn ON will indicate a confirmation of pressure (Oil
Pres Test Passed=YES).
For Refrigerant Pump, a value >=10 psi within 15 seconds
after refrigerant pump is turn ON will indicate a confirmation
of pressure.
5.19.2 - Analog Output
When control test is enabled, the following analog outputs
can be enabled to be driven to the commanded positions
which input in the quick test table.
Head Pressure Valve, Diffuser Actuator, Oil EXV and chiller
status output (Q_CHST)
5.19.3 - Guide Vane Calibration
Guide vane position should be calibrated before startup
chiller.
Guide vane calibration can be started by setting "Quick Test
Enable" to Enable and "GV1 calibration Enable" to Enable.
If the actuator type is digital, then
- The fully closed guide vane feedback resistance will be
in the range of 62.5 Ohms to 688 Ohms
- The fully opened guide vane feedback resistance will
be in the range of 6190 Ohms to 11496 Ohms
Else if the actua.tor type is analog, then
- The fully closed guide vane feedback mA value will be
in the range of 3mA to 5mA
- The fully opened guide vane feedback mA value will
be in the range of 19mA to 20.8mA
When chiller type is 19DV, guide vane 2 also need calibration,
same as guide vane 1.