Honeywell UDC2500 manual Control and Alarm Relay Contact Information, Control Relays, Alarm Relays

Installation

2.4 Control and Alarm Relay Contact Information

Control Relays

ATTENTION

Control relays operate in the standard control mode (that is, energized when output state is on).

Table 2-2 Control Relay Contact Information

Unit Power	Control Relay	Control Relay	Output #1 or #2
	Wiring	Contact	Indicator Status
Off	N.O.	Open	Off
	N.C.	Closed
On	N.O.	Open	Off
		Closed	On
	N.C.	Closed	Off
		Open	On

Alarm Relays

ATTENTION

Alarm relays are designed to operate in a failsafe mode (that is, de-energized during alarm sate). This results in alarm actuation when power is OFF or when initially applied, until the unit completes self diagnostics. If power is lost to the unit, the alarms will de-energize and thus the alarm contacts will close.

Table 2-3 Alarm Relay Contact Information

Unit	Alarm Relay	Variable NOT in Alarm State
Power	Wiring
		Relay	Indicators
		Contact
Off	N.O.	Open	Off
	N.C.	Closed
On	N.O.	Closed	Off
	N.C.	Open

Variable in Alarm State

Relay	Indicators
Contact
Open	Off
Closed
Open
	On
Closed

14 UDC2500 Universal Digital Controller Product Manual 4/07