Product Manual

Wall Mounted Ultrasonic Flowmeter---User Manual
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(PT100 resistor wiring connection)
While prolong the wire of PT100 RTD, please try to use wire with thicker diameter,
and also ensure the same specification for 3 wires to connect PT100 RTD.
Please kindly note the thermal energy measurement circuit and flow measurement circuit are
common-ground.
5.3 Window Menus for Thermal Energy Measurement
Menu window M05: display energy rate (instantaneous Caloric) and total energy (Caloric).
Menu window M06: display the current temperature value of supply T1 and return T2 and their
corresponding resistor values.
Menu window M84: the thermal energy unit selection:
0. GJ (factory default) 1. KC 2.KWh 3. BTU
Menu window M85: select temperature sources 0.from T1,T2(factory default)
1. from AI3,AI4
Menu window M86: Select the Specific Heat Value.
Menu window M87: Turn on or turn off the Energy totalizer.
Menu window M88: Select thermal energy totalizer multiplying factor. Factory default is ‘1’.
Menu window M89:
1.Display the temperature difference
2. Window for entering the lowest temperature difference (temperature cutoff).
Menu window M8
.: Select to which pipe the heat meter is installed, the inlet or outlet pipe.
Menu window M95:
Display the positive and negative energy totalizers
Menu window M-8,M-9,M-A,M-B are used to calibrate temperature measurement system.
5.4 Calibrating Sub-system of Temperature Measurement
The accuracy of temperature measurement part is generally 0.5!"if without calibration. Thus, if
replace PT100 resistor or replace temperature measurement components, the accuracy will be
about 1!#"
In order to gain the accuracy of 0.1!, it is necessary to calibrate temperature measurement part.
It is usually calibrated by using thermostat.
The flow meters use two standard temperature point to calibrate: 50! and 84.5!.