Differential Pressure Sensing

Available on the E306 monitor

The E306-P000 monitor is equipped with the differential sensing that will sense the difference in air pressure between two areas.  To monitor differential pressure the two sensing tubes need to be placed in areas with different pressures, such is an opposites sides of a baffle, above and below a raised floor, or inside and outside of a server rack. Always make sure that the high pressure line is place in the area with higher pressure and the low pressure line is placed in the area with lower pressure.                                    

Monitoring Differential Pressure

By placing one tube in direct path of the flow (i.e. at the base of a server cabinet by the air intake) and the second tube in the ambient area with little air flow (i.e. the top exterior of the server cabinet), the resulting pressure differential will reflect the level of air flow.  Note: This is not a measurement of specific air flow rate, but rather a relative indication. A lower differential pressure will indicate a lower air flow rate, and a higher pressure value a higher flow rate.

The area monitoring the higher pressure (or faster air flow) should use the tube marked with the positive (+) symbol. The area with the lower pressure or slower flow should use the tube marked with the negative (-) symbol. The differential pressure is expressed in Pascals (±500 Pa in 0.2Pa, or ±3% accuracy). 

Server Rack Flow Sensing: In the above application, the differential pressure will increase as the air flow speed increases.

The data for the differential pressure can be viewed on the LCD Display of the E306 module, as well as a Modbus register and SNMP MIB. Pressure data can also been seen on the EMX portal.