42
HELIX™ Manual
(P/N 26291)
Chapter 3: System Design
Rev A (February 2018)
HELIX™ PCU
Fire Suppression System
3.6.2 Detection Circuit Design
The Amerex STRIKE ECS supports up to two detection circuits. Each detection circuit may utilize
Linear Heat Detectors (LHD) as a detection device. The length of Linear Heat Detection (LHD)
required in a system will depend on the size of the PCU. Multiple detection devices may be used in
a single circuit and can be connected in series. Each detection circuit is limited to 100 feet (30.5 m),
including installed LHDs, unless the circuit utilizes only a Communication Cable (P/N 25264
-
XX)
(See Figure 3.6.1c and 3.6.1d). An EOL (P/N 23474) is always required at the end of each circuit
and is included with each STRIKE Unit.
Linear Heat Detectors (LHD) are preset (356ºF/180ºC) heat sensing devices capable of sensing an
overheat condition at any point along its routed path. Features and limitations for LHDs are:
•
Preset device with 356ºF (180ºC) set point
•
Maximum ambient operating temperature: 250ºF (121ºC)
•
One time use device and must be replaced after sensing an overheat condition
•
Flexible (2.5” [64 mm] min. bend radius) for continuous routing along a desired path
•
Suitable for detection over large areas using single LHD
•
Available in various lengths
•
Installed using Quik Seal (P/N 24737) or Compression Seal (P/N 26427) for bulkhead
penetration and LHD Support Clips (P/N 23524)/Split Tubing (P/N 24539) or P
-
Clamps (P/N
18720
-
R) for support at a min. of every 24” (0.61 m)
A typical LHD installation circuit is shown in the following figures (See Figure 3.6.2a & Figure 3.6.2b):
AIR FLOW
Figure 3.6.2a
LHD
(P/N 24744
-
XX)
INSTALLED BEHIND
LAST FILTER BANK
(DOWNSTREAM)
