Detcon DM-100 - Manual (Page 17)

Model DM-100
DM-100 Instruction Manual Rev. 3.3 Page 13 of 40
2.7.2 O
2
Deficiency Sensors
Upon completion of all mechanical mounting and termination of all field wiring, apply system power in the
range of 11-30VDC (24VDC typical) and observe the following normal conditions:
If the sensor has a loop power display installed, the display should read close to 20.9%. If a DVM is used to
measure the 4-20mA output, set the DVM to measure millivolts and connect the leads across TP1 and TP2 on
the terminal board. The DVM should read 173.7±2mV.
The reading should stabilize within 1 to 2 minutes of power-up (assuming a ‘normal’ ambient O
2
concentration).
Initial Operational Tests
After a warm-up period of 5 minutes the sensor should be checked to verify response to O
2
deficiency.
Material Requirements
 Detcon PN 613-120000-700 700 Series Splash Guard with integral Cal Port and Calibration Wind
Guard (P/N 943-000000-000) -OR-
 Detcon PN 943-000006-132 Threaded Calibration Adapter - OR -
 Detcon PN 943-01747-T05 Teflon Calibration Adapter for highly reactive gases
 Detcon Zero Gas: 100% N2 at fixed flow rate of 200-500cc/min
 DVM (if a loop powered display is not installed)
NOTE
The cover of the junction box will need to be removed if there is not a loop powered
display. The area may need to be de-classified.
1. Attach the calibration adapter to the threaded sensor housing or connect tubing to the integral cal port.
Apply the test gas at a controlled flow rate of 200-500cc/min (500cc/min is the recommended flow).
2. If the sensor has a loop power display installed, the display reading should drop to "0". If a DVM is
used to measure the 4-20mA output, set the DVM to measure millivolts and connect the leads across
TP1 and TP2 on the terminal board. The DVM should read 40±2mV.
3. Remove test gas and calibration adapter. If the sensor has a loop power display installed, the display
should return to a reading of 20.9%. The DVM should return to a reading of 173.7mV (17.37mA).
Initial operational tests are complete. DM-100 O
2
deficiency sensors are factory calibrated prior to shipment,
and should not require significant adjustment on start up. A complete calibration test and adjustment should be
performed 16 to 24 hours after power-up. Refer to zero and span calibration instructions in Section 3.3,
Calibration.