Emerson 1.6Controller Board Overview, Controller board components, Introduction, Liebert AC4

Introduction

1.6Controller Board Overview

The Liebert AC4 controller board has connectors for four digital inputs and four digital outputs, as shown below. The board comes complete with light emitting diodes (LEDs) to display the status of connected devices, a serial communications port, a power connection and other features necessary to control your operation.

A - Power	B - Audible
On/Off switch
	horn

P - 24VAC power connector

C - Audible horn D - Common Alarm

jumper connectors

E - Digital output status LEDs

O - LCD	F - Manual
contrast	Override Switch
adjustment	(outputs)
N - LCD	G - Digital output
	connectors
connector	H - Status LEDs
M - DIP	I - Digital output
switch 1	loss-of-power
	jumper
	J - Digital input
	connectors
L - Serial interface	K - Digital input
connector
(RS232/EIA574)	status LEDs

Table 1	Controller board components
	Item	Description	For more information, see:
A - Power On/Off		Power switch for the controller board.	2.4:	Connect Power to the Liebert
switch				AC4
B - Audible horn		Provides audible notification when an alarm occurs.	N/A
C - Audible horn		Jumper to disable the audible horn (factory default is	N/A
jumper		enabled).
		The two common alarm connections are used to connect to	3.0:	Wiring and Connections
		a secondary warning device such as a horn, light or
D - Common Alarm			3.3:	Connecting Common Alarm
		Building Management System (BMS). When an alarm is
				Outputs
connectors		present, the contacts close and the external warning device
			7.4:	Setup System - Setup Common
		is activated/notified. The common alarm contacts may be
				Alarm
		configured to be reset with the Silence button/command.
E - Digital output		Each output has an LED to indicate its status: ON/OFF	1.7:	LED Indicators
status LEDs		(energized/de-energized).
F - Manual Override		Placing the switch in the ON position will turn ON, or
		energize, all four outputs simultaneously. This switch	7.9:	Override Output
Switch (outputs)
		removes all automatic output control from the Liebert AC4.
		Each of the four output connections is a two-state point:	3.0:	Wiring and Connections
G - Digital output		ON/OFF (energized/de-energized).	3.2.2:	Connecting Digital Outputs
connectors		An example of a field digital output is a Liebert	5.5:	View Output Status
		Environmental unit’s remote shutdown input.	7.6:	Setup System - Setup Outputs
H - Status LEDs		Indicates the operational status of the controller board.	1.7:	LED Indicators

Liebert® AC4™ 4