The term ?dissipation loss? can be found in the data sheet for a pressure sensor or pressure transmitter. Reject needs this specification in order to be able to protect the pressure sensor from overheating.
In case a pressure sensor is operated in a hot environment, it might be necessary to limit its electrical energy. If one neglects this aspect, one possibly risks an overheating and with this, in the worst case, a total failure of the instrument. Just how can the correct electrical connection be managed?
Determination of the correct electrical connection on the basis of the dissipation loss
First, the maximum permissible electrical power for the pressure sensor must be known. That is given in the data sheet as the dissipation loss. Please be aware that the dissipation loss can be dependent upon the maximum expected operating temperature of the instrument and must be calculated where necessary.
If the allowable dissipation loss has been determined correctly, then your actual maximum electrical energy for the pressure sensor that occurs can be determined. The determination can be executed expediently in two steps:
1. Determination of the voltage at the pressure transmitter using the following formula:
UPressure transmitter = UVoltage source ? RLoad � Imax. Current supply
2. Calculation of the maximum electrical energy for the pressure transmitter through the next equation:
PPressure transmitter = UPressure transmitter � Imax. Current supply
The maximum electrical energy for the pressure transmitter (PPressure transmitter), that is now known, should be smaller than the permissible dissipation loss. If this is actually the case, both the power supply (UVoltage source) and the load (RLoad) were properly calculated and the electrical energy of the pressure sensor will undoubtedly be within the permissible range under all operating conditions. Consequently, the pressure transmitter will not heat too strongly and will withstand the mandatory operating temperatures.
Note
Should you need any advice, your contact will gladly help you.