Manual
2 • 65-2442RK PPM Hydrogen Transmitter
Description
This section describes the ppm hydrogen transmitter’s components. It is a 4 to 20 mA type
detector head. It consists of the ppm hydrogen detector, amplifier, and junction box.
Figure 1: PPM Hydrogen Transmitter Component Location
PPM Hydrogen Detector
The ppm hydrogen detector is a MOS type (metal oxide semiconductor) detector
packaged in a 1/2 inch NPT nipple with a sintered metal flame arrestor on one end
allowing ambient air to diffuse into the detector. The flame arrestor also contains any
sparks which may occur within the detector. The 1/2 inch NPT mounting threads at the
top of the detector allow you to mount it into the bottom conduit hub of the junction box.
A rainshield screws onto the bottom of the detector (flame arrestor end). The rainshield
helps protect the detector from rain and debris in the monitoring environment. Three
color-coded leads extend from the top of the detector. The leads allow you to connect the
detector to the amplifier.
Mounting Screw
w/ flat and lock washer
Controller Terminal Strip
Detector Terminal Strip
Hydrogen Detector
J-Box
Amplifier
SPAN
ZERO
1-2 Hex
3-4 H2
G
as Select
1
3
4
2
Factory Use
Jumper Strip
Factory Adjust Pot
Load Voltage Pot
Factory Adjust Pot
Zero Pot
Span Pot
- Test Point, Black
Factory Use Jumper Strip
Gas Select Jumper,
In Hydrogen Position
Reducing Bushing,
3/4 NPT to 1/2 NPT
+ Test Point, Red
PWR / SIG
SWBR
DETECTOR










