Carrier 30XW150-400 specifications Enable-Off-Remote Contact Switch SW1, Energy Management Module

Enable-Off-Remote Contact Switch (SW1) —

This switch is installed in all units and provides the owner and service person with a local means of enabling or disabling the machine. It is a 3-position switch and it is used to control the chiller. When switched to the Enable position, the chiller will be under its own control. When switched to the Off position, the chiller will shut down. When switched to the Remote Con- tact position, a field-installed dry contact can be used to start the chiller. The contacts must be capable of handling a 24-vac, 50-mA load. In the Enable and Remote Contact (dry contacts closed) positions, the chiller is allowed to operate and respond to the scheduling configuration, CCN configuration, and set point data.

For units with a Touch Pilot™ display, the position of the Enable/Off/Remote contact switch is ignored except when the Remote Mode operating type is selected. Refer to the Machine Control Methods section on page 20 for more details.

Emergency On/Off Switch (SW2) — This switch is installed in all units. The Emergency On/Off switch should only be used when it is required to shut the chiller off immedi- ately. Power to all modules is interrupted when this switch is off and all outputs from these modules will be turned off.

Energy Management Module (EMM) — The EMM is available as a factory-installed option or as a field-installed accessory. See Fig. 12. The EMM receives 4 to 20 mA inputs for the temperature reset, cooling set point and demand limit functions. The EMM also receives the switch inputs for the field-installed second stage 2-step demand limit and ice done functions. The EMM communicates the status of all inputs with the MBB, and the MBB adjusts the control point, capacity limit, and other functions according to the inputs received. See Table 9.

CAUTION

Care should be taken when interfacing with other manufac- turer’s control systems due to possible power supply differ- ences, full wave bridge versus half wave rectification, which could lead to equipment damage. The two different power supplies cannot be mixed. ComfortLink™ controls use half wave rectification. A signal isolation device should be utilized if incorporating a full wave bridge rectifier sig- nal generating device is used.

J9B J9A

221 221

221 221

100K

100K

-	G +	-	G +
LEN IOS		LEN IOS
			7
	100K		CH
			100K

CH 5CH 6

J8

J7B

100K

CH CH CH CH CH 15 1 2 3 4

CH 14

CH 13

CH 12

J7A

J6

12	24
11	VAC

CH 11b

J5

CH	CH CH		CH	CH	CH	CH	CH	CH	CH
	17	16	17	18	19	20	21	22	23

J1 J2A J2B J3 J4

Fig. 12 — Energy Management Module

a30-4911

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