Led Definitions; Table 16 Leds-Defined - Liebert Static Transfer Switch 2 Installation, Operation & Maintenance Manual

14.1.3 LED Definitions

The following table defines what item that these LEDs monitor:
Table 16 LEDs—Defined
LED
IN1A
IN2A
CB1
CB2
IN1B
IN2B
STS1
STS2
LED_PREF1
LED_PREF2
NOXF
CB3
CB3A
CB4
CB5
OUT
Item Monitored
Source 1 input present
Source 2 input present
Circuit Breaker 1
Circuit Breaker 2
Source 1 parameters
Source 2 parameters
Source 1 SCRs
Source 2 SCRs
Source 1 as the preferred source
Source 2 as the preferred source
Transfer inhibited
Circuit Breaker 3
Circuit Breaker 3A
Circuit breaker 4
Circuit breaker 5
Power present to output load
Action
A green LED is lit if the Source 1
input power is present. This LED
only indicates that power is present
to the power supply; it does not
indicate if the power is within the
programmed tolerances of the unit.
A green LED is lit if the Source 2
input power is present. This LED
only indicates that power is present
to the power supply; it does not
indicate if the power is within the
programmed tolerances of the unit
A green LED is lit if CB1 is closed,
indicating power is flowing to the
static transfer switch from Source 1.
A green LED is lit if CB2 is closed,
indicating power is flowing to the
static transfer switch from Source 2.
A green LED is lit if Source 1 power
is within the programmed tolerance
for all phases.
A green LED is lit if Source 2 power
is within the programmed tolerance
for all phases.
A green LED is lit when the SCRs
for Source 1 are closed.
A green LED is lit when the SCRs
for Source 2 are closed.
A green LED is lit if the button has
been pushed to set Source 1 as the
preferred source.
A green LED is lit if the button has
been pushed to set Source 2 as the
preferred source.
A yellow (amber) LED is lit when
source transfers are inhibited
(locked out) by a hardware
condition. Connect a PC terminal to
the STS2 to locate the exact cause.
See Communication Interfaces
for PC terminal commands.
A green LED is lit if the output
breaker/switch is closed.
A green LED is lit if the output
breaker/switch is closed. CB3A is
installed on units with dual output
breakers.
A yellow LED is lit if the Source 1
bypass breaker/switch is closed.
A yellow LED is lit if the Source 2
bypass breaker/switch is closed.
A green LED is lit to indicate that
power is present on the output load.
Operating the LED Display STS2 101