User guide
               DM-534C Oxygen Sensor Assembly 
DM-534C O2 Sensor Instruction Manual    Rev. 1.4  Page 3 of 18 
Figure 4 Explosion proof enclosures 
2.0  PRINCIPLE OF OPERATION 
Method of detection is by a controlled rate of diffusion. Air and gas diffuse through a sintered stainless steel 
filter and a diffusion barrier. As oxygen is adsorbed into the electrolyte solution a current is generated between 
the cathode and anode electrodes. This current output rises with increases in oxygen concentration and 
reverses with lower concentrations. The quick response of the cell results in continuous monitoring of ambient 
air conditions. 
Figure 5 Functional Block Diagram 
3.0   APPLICATION 
Model DM-534C 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. 
3.1   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. 










