User's Manual for CM6G - Yokogawa

6.3 Differential Pressure Detection Part 6-5In order to calculate the differential pressure correction value, the flow rate is acquired from theorifice as a differential pressure and converted to an electrical signal using the differential pressuretransmitter. The orifice is housed in a constant temperature chamber (orifice assembly), thetemperature of which is maintained at approximately 50°C by the temperature controller, to preventthe temperature drift of the actual flow rate.When the temperature exceeds 90°C, the safety thermostat is activated to shut off the heater powersupply. When the temperature falls after the power supply is shut off, the alarm thermostat is activatedto provide an alarm (closed contact) output.WARNINGPower is supplied to the differential pressure transmitter and the temperature controller from thecalorie detector. To operate the transmitter and the controller, turn on the calorie detector switch of theswitch box and the POWER switch on the front panel of the calorie detector.MAIN PANELORIFICE ASSEMBLYTEMPERATURECONTROLLERDIFFERENTIAL PRESSURETRANSMITTERFigure 6.5 Differential Pressure Detection EquipmentIM 11R02A01-02E