35-3001-13-02 Carbon Dioxide/Oxygen Sample-Draw Detector • 9
Main Circuit Board
The main circuit board includes the detector/amp terminal strip, interconnect terminal strip, oxygen sensor
terminal strip, pump connector, and flowmeter circuit board connector (see Figure 1).
Detector/Amp Terminal Strip
The detector/amp terminal strip is the upper twelve-point terminal strip in the bottom right corner of the main
circuit board. Use the detector/amp terminal strip to connect the carbon dioxide sensor to the main circuit board.
NOTE:
The carbon dioxide sensor is factory-wired to the main circuit board. See the “Installation” section on
page 11 for all wiring procedures related to the sample-draw detector.
Interconnect Terminal Strip
The interconnect terminal strip is the lower twelve-point terminal strip in the bottom right corner of the main
circuit board. Use the interconnect terminal strip to connect the sample-draw detector to a controller.
Oxygen Sensor Terminal Strip
The oxygen sensor terminal strip is a two-point terminal strip in the upper right corner of the main circuit board.
Use the oxygen sensor terminal strip to connect the oxygen sensor to the main circuit board.
NOTE:
The oxygen sensor is factory-wired to the main circuit board. See the “Installation” section on page 11
for all wiring procedures related to the sample-draw detector.
Pump Connector
The pump connector is the two-point connector below the oxygen terminal strip in the upper right corner of the
main circuit board. Use the pump connector to connect the pump to the main circuit board.
NOTE:
The pump is factory-wired to the main circuit board. See “Installation” on page 11 for all wiring
procedures related to the sample-draw detector.
Flowmeter Circuit Board Connector
The flowmeter circuit board connector is a six-position connector in the upper left corner of the main circuit
board. Use the flowmeter circuit board connector to connect the flowmeter circuit board to the main circuit
board.
NOTE:
The flowmeter circuit board is factory wired to the main circuit board. See “Installation” on page 11 for
all wiring procedures related to the sample-draw detector.
Flowmeter Circuit Board
The flowmeter circuit board is mounted to the left side of the main circuit board using standoffs. It includes the
flowmeter, sensor flow control valve, status LEDs, pressure switch, and pump reset switch.
Flowmeter
The flowmeter is mounted to the right side of the flowmeter circuit board. You can see it through the window in
the door. A ball in the flowmeter column indicates the flow rate to the sensor. The flowmeter measures the flow
in the range 0.2 to 2.0 SCFH (Standard Cubic Feet per Hour). The optimum flow rate is 1.0 SCFH.
Sensor Flow Control Valve
The sensor flow control valve is mounted to the flowmeter circuit board above the flowmeter. The sensor flow
control valve adjusts the flow rate to the detector. Turn the valve’s knob clockwise to increase the flow and
counterclockwise to decrease the flow.
