Detcon FP-524D-HRT - Manual (Page 11)

Model FP-524D-HRT
FP-524D-HRT Instruction Manual Rev. 0.1 Page 7 of 48
the active detector’s catalytic ability and cause a permanent reduction in the span sensitivity. Examples of
typical poisons are: silicone oils and greases, siloxanes (HMDS), H
2
S, anti-knock petrol additives, and
phosphate esters. Activated carbon filters can be used to provide additional protection from poisoning in most
cases.
The presence of such inhibitors and poisons in an area does not preclude the use of this sensor technology,
although it is likely that the sensor lifetime will be shorter as a result. Use of this sensor in these environments
may require more frequent calibration checks to ensure safe system performance.
2.4 Mounting Installation
The FP-524D-HRT should be vertically oriented so that the sensor points straight downward. The explosion-
proof enclosure or junction box would then typically be mounted on a wall or pole (See Figure 9). Detcon
provides a selection of standard junction boxes in both Aluminum and Stainless Steel.
NOTE: Do not use Teflon Tape or any other type of Pipe Thread material on the ¾” threads
unless the unit is mounted in a severe or harsh environment. Metal-on-metal contact must be
maintained to provide a solid electrical ground path. If Teflon Tape is used the Sensor must be
externally grounded using a ground strap.
When mounting on a pole, secure the Junction Box to a suitable mounting plate and attach the mounting plate
to the pole using U-Bolts. (Pole-Mounting brackets for Detcon Junction Box’s are available separately.)
8-32 tapped
ground point
4.6"
3
4 NPT Ports
6.125"
5.5"
6.985"
1
4 " mounting holes
5.25"
W
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LEL Sensor
Splash Guard
2"
0.5"
Cal Port
2.1"
Figure 9 Typical Outline and Mounting Dimensions