Carrier 30XW150-400 Item Expansion Path Value Crst, CRT1, CRT2, Dgrc, CRS1, CRS2, CRV1, CRV2

To configure this option with the Touch Pilot™ display:

DISPLAY NAME	PATH	LINE NO.	VALUE
Cooling Reset	Main		Default =0
		19	(No Reset)
Select	Menu→ Config→ USER
			2 (Delta T)
Delta T No	Main	7	Default =
Reset Temp	Menu→ Setpoint→ SETPOINT		0 F (0 C)
Delta T Full	Main	8	Default =
Reset Temp	Menu→ Setpoint→ SETPOINT		0 F (0 C)
Cooling Reset	Main	13	Default =
Deg. Value	Menu→ Setpoint→ SETPOINT		0 F (0 C)

To configure this option with the Navigator™ display:

ITEM	ITEM EXPANSION	PATH	VALUE
CRST	Cooling Reset	Configuration→ RSET	Default =
			No Reset
	Type
			Delta T Temp
CRT1	Delta T No	Setpoints→ COOL	Default =
	Reset Temp		0 F (0 C)
CRT2	Delta T Full	Setpoints→ COOL	Default =
	Reset Temp		0 F (0 C)
DGRC	Degrees Cool	Setpoints→ COOL	Default =
	Reset		0 F (0 C)

In the example in Fig. 21 using Return Water Temperature Reset, the chilled water temperature will be reset by 5° F (2.8° C) when the Fluid Temperature Difference is 2° F (1.1° C) and 0° F (0° C) reset when the Temperature Difference is 10° F.

SPACE TEMPERATURE RESET — The control system is also capable of temperature reset based on space temperature (SPT). An accessory sensor must be used for SPT reset (33ZCT55SPT). The Energy Management Module (EMM) is also required for temperature reset using space temperature.

To use Space Temperature Reset, four variables must be configured. Cooling Reset Type (Cooling Reset Select, CRST) must be enabled. The space temperature at which no tempera- ture reset is required, Space T No Reset Temp (Space T No Reset Value, CRS1) must be set. The space temperature at which full temperature reset is required, Space T Full Reset Temp (Space T Full Reset Value, CRS2) must be set. Finally, the amount of temperature reset desired, Degrees Cool Reset (Cooling Reset Deg. Value, DRGC), must be set.

To configure this option with the Touch Pilot display:

DISPLAY NAME	PATH	LINE	VALUE
		NO.
Cooling Reset	Main Menu		Default =0
		19	(No Reset)
Select	→ Config→ USER
			4 (Space Temp)
Space T No	Main Menu	11	Default =
Reset Value	→ Setpoint→ SETPOINT		14 F (–10 C)
Space T Full	Main Menu	12	Default =
Reset Value	→ Setpoint→ SETPOINT		14 F (–10 C)
Cooling Reset	Main Menu	13	Default =
Deg. Value	→ Setpoint→ SETPOINT		0 F (0 C)

To configure this option with the Navigator display:

ITEM	ITEM EXPANSION	PATH	VALUE
CRST		Configuration→ RSET	Default =
	Cooling Reset Type		No Reset
			Space Temp
CRS1	Space T No Reset	Setpoints→ COOL	Default =
	Temp		14 F (–10 C)
CRS2	Space T Full Reset	Setpoints→ COOL	Default =
	Temp		14 F (–10 C)
DGRC	Degrees Cool Reset	Setpoints→ COOL	Default =
			0 F (0 C)

In the space temperature reset example in Fig. 22, 0° F (0° C) chilled water set point reset at 72 F (22.2 C) space temperature and 6° F (3.3° C) reset at 68 F (20.0 C) space temperature.

4-20 mA TEMPERATURE RESET — The control system is also capable of temperature reset based on an externally pow- ered 4 to 20 mA signal. The Energy Management Module (EMM) is required for temperature reset using a 4 to 20 mA signal.

To use 4-20 mA Temperature Reset, four variables must be configured. Cooling Reset Type (Cooling Reset Select, CRST) must be enabled. The milliamp signal at which no temperature reset is required, Current No Reset Value (Current No Reset Value, CRV1), must be set. The milliamp signal at which full temperature reset is required, Current Full Reset Value (Cur- rent Full Reset Value, CRV2), must be set. Finally, the amount of temperature reset desired, Degrees Cool Reset (Cooling Reset Deg. Value, DRGC), must be set.

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. Connec- tion of control devices with different power supplies may result in permanent damage. The ComfortLink™ controls incorporate power supplies with half wave rectification. A signal isolation device should be utilized if the signal gen- erator incorporates a full wave bridge rectifier.

To configure this option with the Touch Pilot™ display:

DISPLAY NAME	PATH	LINE NO.	VALUE
Cooling Reset			Default =0
	Main Menu	19	(No Reset)
Select	→ Config→ USER		3 (4-20mA
			Control)
Current No	Main Menu	9	Default = 0.0
Reset Value	→ Setpoint→ SETPOINT
Current Full	Main Menu	10	Default = 0.0
Reset Value	→ Setpoint→ SETPOINT
Cooling Reset	Main Menu	13	Default =
Deg. Value	→ Setpoint→ SETPOINT		0.0 F (0.0 C)

To configure this option with the Navigator™ display:

ITEM	ITEM EXPANSION	PATH	VALUE
CRST	Cooling Reset	Configuration→ RSET	Default =
			No Reset
	Type
			4-20mA Input
CRV1	Current No	Setpoints→ COOL	Default = 0.0
	Reset Temp
CRV2	Current Full	Setpoints→ COOL	Default = 0.0
	Reset Temp
DGRC	Degrees Cool	Setpoints→ COOL	Default = 0.0
	Reset

In the example in Fig. 23, at 4 mA no reset takes place and at 20 mA, 5° F (2.8° C) chilled water set point reset is required.

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