DM-634C Oxygen Sensor Assembly
DM-634C O2 Sensor Instruction Manual Rev. .066
Page 4 of 25
3.2
Application
Model DM-634 MicroSafe™ sensors are designed to detect and monitor oxygen deficiency in ambient air in
the range of 0-25%. Minimum sensitivity and scale resolution is 0.1%. Operating temperature range is -4° F.
to +122° F. While the sensor is capable of operating outside these temperatures, performance specifications
are verified within the limit.
3.2.1
Sensor Placement/Mounting
Sensor location should be reviewed by facility engineering and safety personnel. Area leak sources and
perimeter mounting are typically used to determine number and location of sensors. The sensors are generally
located 2 - 4 feet above grade.
3.2.2
Interference Data
Table 1
Interference Data
Methane
100% = 0
Hydrocarbons
100% = 0
Hydrogen
100% = < 2%
Carbon Monoxide
20% = < 0.5%
3.3
Specifications
Method of Detection
Air battery diffusion/adsorption
Electrical Classification
Class I; Groups B, C, D; Div. 1.
Response Time (T90)
T90 < 20 seconds
Clearing Time
90% < 20 seconds
Repeatability
± 2% FS
Range
0-25% O2
Operating Temperature
-
4° to +122° F
Accuracy
± 2% FS
Sensor Warranty
2 year conditional
Power Consumption
Normal Operation = 28mA (<3/4 watt); Full Alarm = 85mA (2 watt)
Output
3 relays (alarm 1, alarm 2, and fault) contact rated 5 amps @ 250VAC
5 amps @ 30VDC; Linear 4-20mA DC; RS-485 Modbus™
Input Voltage
22.5-28 VDC