Emerson AC4 user manual 7.6.2Define Operating or Standby Mode

System and Control Options

7.6.2Define Operating or Standby Mode

Each output may be defined as Operating (OP), Standby (ST), or Not Used (NU). This setting takes precedence over any setting in the override menu (see 7.9 Override Output).

Default settings are:

•Outputs 1, 2 and 3 are in Operating (OP) mode

•Output 4 is in Standby (ST) mode

To change the mode:

•From the Setup Outputs Menu, shown at right, use the arrows ↑↓ to choose Mode for the selected output and press Enter ↵.

•To change the output’s mode, use the arrows ↑↓ to choose one of these options:

•OP (Operating)

•ST (Standby)

•NU (Not Used)

•Press Enter ↵.

7.6.3Enable or Disable an Output Device in Alarm Status

You may choose whether to Enable or Disable an output when the connected device is in alarm status. The default setting for all output points is Enabled.

•From the Setup Outputs Menu, choose In Alarm, as shown at right, and press Enter ↵.

•To make a change, use the arrows ↑↓ to choose E (Enable) or

D (Disable) to determine what happens when an alarm is detected in the device.

•Press Enter ↵.

7.6.4Configure Output for Loss of Power (“Fail-Safe”)

Setup Outputs Menu

SETUP DEVICE_1 NORM OPEN/CLOSE: NO

>MODE: OPERATING

↑↓=NEXT ↵=SELECT IN ALARM: ENABLE

Set Mode

SET MODE: OP

↑↓=OP/ST/NU ↵=EDIT

Setup Outputs Menu

SETUP DEVICE_1 NORM OPEN/CLOSE: NO MODE: OPERATING ↑↓=NEXT ↵=SELECT

> IN ALARM: ENABLE

Change State in Alarm

STATE OF DEVICE IN ALARM: DISABLE

↑↓=E/D ↵=EDIT

Each output has an associated jumper that can help prevent undesired effects when the controller board loses power. For example, without the proper fail-safe jumper setting, a loss of power might close a switch that is Normally Open (NO)—perhaps shutting off an environmental unit or a fan or closing a valve.

This fail-safe jumper setting is unrelated to configuring an output as Normally Open (NO) or Normally Closed (NC), as described in 7.6.1 Define Output as Normally Open or Normally Closed.

To configure a digital output jumper for a loss of power:

•Set the jumper in the “OFF” position (factory default) to make the output Normally Open (NO).

•Set the jumper in the “ON” position to make the output Normally Closed (NC).

For more information, see 3.2.3 Setting the Digital Output Jumpers.

35 Liebert® AC4™