A common question that comes up when working on filter monitoring applications is
“Can I just use two separate pressure transducers to measure the pressure differential?”
The answer is yes, two separate pressure transducers can be used to measure the differential pressure of a filter application. However, there are some potential issues that first need to be considered.
The first issue has to do with compounded inaccuracies. If you are using two pressure transducers, each with a ± 0.5% accuracy, your potential inaccuracy is doubled to ± 1%. If you were to instead use the CS14 Differential Pressure Transducer, you would only need to consider the accuracy of the single transducer, in this case ± 0.25% BFSL (± 0.5% for 2 PSI & below).
Also, while we temperature condition every sensor during the manufacturing process, it is possible for each transducer to behave differently in varying temperature conditions. For example, if the ambient temperature of the application goes from room temperature to 55°C, the upstream transducer could have a TC Span error of -0.5% while the downstream transducer has a TC Span error of +0.5%. Using a dedicated differential pressure transducer would eliminate this compounded inaccuracy potential.
The second issue is potential user error. When two single pressure transducers are used, customers will need to create a program or manually calculate the difference in readings from the upstream and downstream transducer. This introduces the potential for a mistake to be made which, if not caught early, could result in damage to equipment due to lack of flow in the system post filter or contamination of the system’s media due to a overly clogged filter. Our differential pressure transducers automatically calculate the difference in pressure from P1 to P2 and transmit a linear output signal to your PLC or control panel.