Carrier 30XW150-400 specifications 4 to 20 mA Demand Limit Capacity, mA Demand Limit Signal

	100
	90
	80
	70
Limit	60							mA For 0% Demand Limit,
									DMZE
Demand	50
	40
%
	30
	20				mA For 100% Demand Limit,
						DMMX
	10
	0
	0	2	4	6	8	10	12	14	16	18	20
					mA Demand Limit Signal						a30-4831

Fig. 24 — 4 to 20 mA Demand Limit (Capacity)

To configure this option with the Navigator display:

ITEM	ITEM EXPANSION	PATH	VALUE
DMDC	Demand Limit	Configuration→ RSET	4-20MA INPUT
			Default =
	Select		NONE
DMMX	mA for 100%	Configuration→ RSET	Default =
	Demand Lim		0.0 mA
DMZE	mA for 0%	Configuration→ RSET	Default =
	Demand Limit		10.0 mA
CUR.S	Current Limit	Configuration→ OPTN	YES
	Select		Default: NO
CUR.F	Current Limit	Configuration→ OPTN	Default =
	at 100%		2000

In the following example, a 4 mA signal is Demand Limit for compressor current is 2000 amps and a 20 mA Demand Limit signal corresponds with a compressor current of 0 amps. The 4 to 20 mA signal is connected to TB6-1 and TB6-2. The demand limit is a linear interpolation between the two values entered. If the machine receives a 12 mA signal, the machine controls will limit the total compressor current capacity to 1000 amps. See Fig. 25.

CCN LOADSHED CONTROLLED DEMAND LIMIT — To configure Demand Limit for CCN Loadshed control, the unit Operating Type Control must be in CCN control. With the Touch Pilot™ display, the machine must be started with CCN Control. For the Navigator™ display, the Operating Control Type (I/O Button, OPER) must be CCN CONTROL.

The unit must be controlled by a Chillervisor module. The Chillervisor module can force the demand limit variable and directly control the capacity of the machine. Additionally, the unit’s set point will be artificially lowered to force the chiller to load to the demand limit value.

Ice Storage Operation — Chiller operation can be configured to make and store ice. The energy management module and an Ice Done Switch are required for operation in the Ice Mode. In this configuration, the machine can operate with up to three cooling set points: Cooling Set Point 1 (Cool- ing Setpoint 1, CSP.1) is used during the Occupied period; Cooling Set Point 2 (Cooling Setpoint 2, CSP.2) is used dur- ing the Unoccupied period when the ice build is complete (Ice Done Switch is closed); and Cooling Ice Set Point (Cooling

Ice Setpoint, CSP.3) is used during the unoccupied period while ice is building (Ice Done Switch is open).

To configure this option with the Touch Pilot display:

DISPLAY NAME	PATH	LINE NO.	VALUE
Ice Mode Enable	Config→ USER	42	Yes

To configure this option with the Navigator display:

ITEM	ITEM EXPANSION	PATH	VALUE
ICE.M	Ice Mode Enable	Configuration→ OPTN	ENBL

A power cycle is required for the values to take effect.

Broadcast Configuration — The 30XW chiller is ca- pable of broadcasting time, date, and holiday status to all ele- ments in the CCN system. In the stand-alone mode, broadcast must be activated to utilize holiday schedules and adjust for daylight saving time. If the chiller is to be connected to a CCN system, determine which system element is to be the network broadcaster to all other system elements. Broadcast is activated and deactivated in the BRODEFS Table. It is accessible from Touch Pilot display (Config→ BRODEFS) or through Network Service Tool. It is not accessible through Navigator display.

Only one element should be configured as a broadcaster. If a broadcast is activated by a device that has been designated as a network broadcaster, then broadcasted time, date, and holiday status will be updated over the CCN system. If broadcast is en- abled, a broadcast acknowledger must also be enabled. The ac- knowledger cannot be the same machine as the broadcasting machine.

ACTIVATE — The Activate variable enables the broadcast function of the ComfortLink controls. If this variable is set to 0, this function is not used and holiday schedules and daylight savings compensation are not possible. Setting this variable to 1 allows the machine to broadcast and receive broadcasts on the network. The following information is broadcast: the time with compensation for daylight savings, date, and holiday flag.

41