Liebert POWER PROTECTION STATIC TRANSFER SWITCH User Manual

The service terminal interface parameters are the following settings and cannot be changed.

The STS2 is configured to allow the unit’s electronics to be bypassed to either input source for mainte-

nance without interruption of power to the load. 
The STS2 is furnished with key-interlocked maintenance bypass breakers to configure the bypass.
STS2 units have all electronics isolated from the input, output, and bypass connections to allow safe 

servicing of any components without access to hazardous voltages when the unit is in maintenance 

bypass.
See 10.4 - Maintenance Bypass on page 67 for instructions using the Color LCD Graphical Display 

unit and 14.2.3 - Maintenance Bypass on page 107 for instructions using the LED units.

All STS2 units are fuseless and are UL rated for use with upstream circuit breakers only. 

The following options are available for the STS2:

See 6.0 - Options for more information.

Interface 

RS-232 Using EIA Voltage Levels

Baud Rate 

9600

Parity None
Number of Data Bits 

8

Number of Stop Bits 

1

Hardware Flow Control 

Off

Terminator <CR> 

<LF>

Handshaking Not 

supported

Structure Full 

duplex

Local Echo 

Off

Optimized Transfer

LED Display

Redundant Output Breaker

Network Interface Card (NIC)

Distribution Cabinet With I-Line Panelboard

Seismic Floor Stand - 18", 24", 30" and 36"

Input Junction Boxes and Cable

Export Crating

Comms Board w/SiteScan and Modem Interface

Internal Modem

Input Contact Isolator Board

Remote Source Selection

Programmable Relay Board

Key Lockout Switch