Carrier AquaForce B Series - Page 43

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4 TO 20 MA TEMPERATURE RESET
The control system is also capable of temperature reset based
on an externally powered 4 to 20 mA signal. The EMM is re-
quired for temperature reset using a 4 to 20 mA signal.
To use 4 to 20 mA Temperature Reset, four variables must be
configured: Cooling Reset Select, Current No Reset Value
(milliamp signal at which no temperature reset is required),
Current Full Reset Value (milliamp signal at which full tem-
perature reset is required), and Cooling Reset Deg Value (the
maximum amount of temperature reset desired).
To configure this option with the Carrier Controller display:
In the example in Fig. 41, at 4 mA no reset takes place and at
20 mA, 5°F (2.8°C) chilled water set point reset is required.
SPACE TEMPERATURE RESET
The control system is also capable of temperature reset
based on space temperature. The EMM and accessory sen-
sor (P/N 33ZCT55SPT) are required for temperature reset
using space temperature. This sensor measures the space
(room) temperature for the purpose of set point reset. Only
units with the optional energy management module are fit-
ted with this sensor.
To use Space Temperature Reset, four variables must be con-
figured: Cooling Reset Select, Space T No Reset Value (space
temperature at which no temperature reset is required), Space T
Full Reset Value (space temperature at which full temperature
reset is required), and Cooling Reset Deg Value (the maximum
amount of temperature reset desired).
To configure this option with the Carrier Controller display:
In the space temperature reset example in Fig. 42, a reset of
6°F (3.3°C) is applied when the space temperature is 68°F
(20.0°C) and no reset takes place when the space temperature
is 72°F (22.2°C).
Fig. 41 — Example: 4 to 20 mA Temperature Reset
CAUTION
Care should be taken when interfacing with other control
systems due to possible power supply differences such as a
full wave bridge versus a half wave rectification. Connection
of control devices with different power supplies may result in
permanent damage. Carrier Controller controls incorporate
power supplies with half wave rectification. A signal isola-
tion device should be utilized if the signal generator incorpo-
rates a full wave bridge rectifier.
DISPLAY NAME PATH VALUE
Cooling Reset
Select
Main Menu

Configuration Menu 
Reset Configuration
Default = 3
0=None,
1=OAT
2=Delta T,
3=4 to 20mA control
4=Space Temp
Current No
Reset Value
Default = 0mA
Range 0 to 20mA
Current Full
Reset Value
Default = 0mA
Range 0 to 20mA
Cooling Reset
Deg Value
Default = 0°F (0°C)
Range –30 to 30°F
(–16.7 to 16.6°C)
DISPLAY NAME PATH VALUE
Cooling Reset
Select
Main Menu

Configuration Menu 
Reset Configuration
Default = 4
0=None,
1=OAT
2=Delta T,
3=4 to 20mA control
4=Space Temp
Space T No
Reset Value
Default = 14°F (7.8°C)
Range 14 to 125°F
(7.8 to 69.4°C)
Space T Full
Reset Value
Default = 14°F (7.8°C)
Range 14 to 125°F
(7.8 to 69.4°C)
Cooling Reset
Deg Value
Default = 0°F (0°C)
Range –30 to 30°F
(–16.7 to 16.6°C)
0
1
2
3
4
5
6
0241010
mA Signal
Degrees Reset (deg F)
2
Cooling Reset
Deg. Value
(cr_deg)
Current No Reset Va lue
(v_hr_no)
Current Full Reset Value
(v_hr_fu)
46 8
12 16 18
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