Liebert POWER PROTECTION STATIC TRANSFER SWITCH User Manual

Page of 152
STS2 Touch Screen Display
97
Configuring the Programmable Relay Board Settings
The STS2 can contain up to two Programmable Relay Boards (PRB) that can trigger an external 
device when an event occurs in the static transfer switch. For example, if Source 1 fails, an external 
light flashes.
See 6.1 - Programmable Relay Board for more information on the PRBs.
The Programmable Relay Board dialog box with two options: STANDARD SET and USER DEFINED 
SET. The STANDARD SET are the factory-configured settings.
The STANDARD SET for the Programmable Relay Board settings are:
The USER DEFINED SET allows you to assign faults and alarms to each contact on the relay boards.
Utilizing the USER DEFINED SET, you can also select Input Contact Isolators to associate with a 
programmable relay. 
In addition individual events, three other assignment choices are available:
• SELECT ALL sends a summary event to the selected relay whenever any event occurs. If this set-
ting is selected for a relay, no other event needs to be assigned for that relay.
• ON SOURCE 1 or ON SOURCE 2 can be assigned to a relay to send a notification when that 
source is being used by the load.
Once configured, the static transfer switch continuously checks the status of the items defined for 
each contact and updates the state of the relay.
To configure your programmable relay boards for user defined settings:
1. Select PROG. RELAY BOARD # x from the Comm Options dialog box, where x is the 
corresponding board number.
The Prog. Relay Board dialog box is displayed.
Table 15
Standard Settings for Programmable Relays
Relay
Setting
Definition
1
SOURCE 1 FAIL
Source 1 failure.
2
SOURCE 2 FAIL
Source 2 failure.
3
BYPASS CB4 CLOSED
Switch (CB4) is closed, Source 1 is bypassed.
4
BYPASS CB5 CLOSED
Switch (CB 5) is closed, Source 2 is bypassed.
5
TRANSFER INHIBIT
A transfer between Source 1 and Source 2 is being restrained.
6
OUT OF SYNC
The phase difference between sources 1 and 2 exceeds the 
allowable threshold for transfer,
7
EQUIP OVER TEMP
The ambient temperature of the STS2
 
exceeds the 
recommended threshold for operation.
8
blank
No setting.