Liebert CHALLENGER 3000 - Manual (Page 51)

Component Operation and Maintenance
43
Firestat
The optional firestat is a bimetal operated sensing device with a normally closed switch. This device
will shut down the entire unit when the inlet air temperature exceeds a preset point. It is connected
between terminals 1 and 2 at plug P39.
Smoke Detector
The optional smoke detector power supply is located on the base of the upflow units, and at the top of
downflow units. It is constantly sampling return air through a tube. No adjustments are required.
Water Detection Sensor
The optional water detection devices available are a point leak detection sensor and a zone leak detec-
tion kit.
Figure 7 Liebert leak detection units
The point leak detection sensor provides leak detection at a critical point. A simple two-wire connec-
tion signals the alarms at a Liebert environmental unit or at a monitoring panel. Run wires to the
Liebert unit and connect them to terminals 24 and 51, 55 or 56. Use NEC Class 2, 24V wiring. The
sensor contains a solid state switch that closes when water is detected by the twin sensor probes. The
sensor is hermetically sealed in all thread PVC nipple and is to be mounted where water problems
may occur. The sensor should be located 6-8 feet (2-2.5m) from the environmental control unit in a
wet trap or near a floor drain. It should not be mounted directly under the unit.
Figure 8 Recommended liquid sensor locations
!
CAUTION
Do not use near flammable liquids or for flammable liquid detection.
Liquitect Point Leak
Detection Sensor
LT460 Zone Leak
Detection Kit
Recommended
Liquitect location
Liebert unit
Floor drain