ENMET ISA-RAL-M - Manual (Page 8)

ENMET Corporation ISA-RAL-M, ISA-RAH-M
4
3.3 Sample Head Assembly
The sample head connects to a compressed air line. This unit continuously monitors the respiratory lines for carbon
monoxide levels. Figure 4 illustrates this unit. Assembly parts are listed and defined below.
Pressure Regulator Reduces the pressure of a small sample of air from the compressed air line
before passing over the sensor. It includes a meter to measure the pressure in
pounds per square inch (psi) at the regulator exit.
Quick Release For quick connect/disconnect; fits into the port of an air line.
Pneumatic Fitting Air line filter unit and ENMET calibration adapter (03605-001). Air inlet
fitting is a Milton 727, compatible with Hansen 1000 series. If you substitute
other fittings, the calibration fixture must also be changed.
Humidifier Plastic bottle. This adds moisture to the air sample that passes over the sensor.
Metallic Oxide
Semiconductor
Sensor Solid-state gas sensing element contained in sensor housing. When the
amount of CO in the air passing over the sensor increases to a preset level, the
equipment alarms and relays activate.
Metering Orifice This replaceable assembly has a tiny orifice to ensure constant flow of air
between the humidifier and pressure regulator.
Hydrocarbon Filter To enhance low level calibrations by removal of hydrocarbon vapors from the
air sample. Supplied on ISA-RAL-M P/N 04526-001.
Figure 4: Sample Head Assembly
Quick Release
Fitting
Hydrocarbon Filter
Metallic Oxide
Semiconductor
Sensor
Pressure
Regulator
Humidifier
(Fill to Upper Water Level Mark)
Metering Orifice
Sensor Cable
See Cautions noted in
Section 4 Step 5