beautypg.com

Detection system, Sensor the infrared ch – RKI Instruments 35-3010RKA-07 User Manual

Page 9

background image

35-3010RKA-07 Sample-Draw Detector • 5

Flow Blocks

Both flow blocks are located in the lower right corner of the sample-draw detector. The
oxygen and H

2

S sensors are installed in the larger flow block. The smaller flow block

houses the IR CH

4

sensor. The flow blocks route the sampled air to each sensor.

EXHAUST Fitting

The EXHAUST fitting on the bottom of the housing allows the gas sample to exit the
sample-draw detector. The EXHAUST fitting accepts 1/4 in. rigid tubing. See
“Installation” on page 9 to connect tubing to the EXHAUST fitting.

Detection System

The detection system consists of the gas sensors, LEL and oxygen transmitters, preamp
circuit board, and the main circuit board.

IR CH

4

Sensor

The infrared CH

4

sensor is installed in the smaller flow block in the lower right corner. A

small circuit board with a cable mates to it and retains it in the block. The cable is wired to
the main PCB.

Oxygen Sensor

The oxygen sensor is installed in the lower right of the larger flow block. It consists of a
cylindrical body which houses the detection elements and a cable which terminates in a
round 7-pin male connector. The sensor connector mates to a 7-position socket that is
wired to the main PCB.

Carbon Monoxide Sensor

The CO sensor position in the flow block is occupied by a plastic dummy plug in the
35-3010RKA-07.

Hydrogen Sulfide Gas Sensor

The hydrogen sulfide gas sensor is installed in the upper right side of the flow block. It
has 4 pins which mate with sockets in the preamp circuit board.

Figure 3: LEL & Oxygen Transmitters

BATT

24 V

Test Point TP-

Sensor Terminal
Strip

Oxygen
Transmitter

FB

+

+

TOXIC

OXY

G

Transmitter Type Selector,
Set To OXY

Interconnect
Terminal Strip

Span Pot

Zero Pot

TP

+

TP

-

4/2 0

TOXIC

Test Point TP+

RD

B K

W

OXY

SPAN

LEL Transmitter

Interconnect

Terminal Strip

Test Point TP-

Span Pot

Zero Pot

ZERO

Test Point TP+