Servomex SERVOTOUGH LaserExact 2950, Руководство оператора

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SERVOTOUGH LaserExact Monitor, Operator Manual 02950001A_1
SERVICE PROGRAM
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concentration through the ideal gas law. Therefore, correct setting of gas pressure
and temperature is important for the accuracy of the measurement.
Current
pressure and Current temperature are the values used for calculation at present.
These values are only downloaded from the instrument after an update of
parameters or explicitly after pressing <Reload readings (P, T, date)>.
Note that the gas pressure is always specified in bar
absolute . To convert
pressure from bar gauge to bar absolute use the following relation:
P(bara) = 1.013 + P(barg)
To convert pressure from Psig to bar absolute use the following relation:
P(bara) = 1.013 + P(psig)/14.5
Note that the gas temperature is always specified in Celsius. To convert
temperature from Fahrenheit to Celsius the following relation can be used:
T(C) = (T(F) – 32)/1.8
To convert temperature from Kelvin to Celsius the following approximate relation
can be used:
T(C) = T(K) - 273
Pressure and temperature input method
<Pressure/Temperature input method> defines if the values are fixed or read with
one of the following methods: Current loop, Internal, Spectral, and Serial.
If method “Current loop” is activated the values are input from the corresponding
4-20 mA current input. In this case the PLC 4 mA and PLC 20 mA values must be
specified.
Method “Internal” sets the gas pressure equal to the ambient pressure measured
by the internal pressure sensor (
Air pressure in Measurements menu). The gas
temperature is set equal to the average of the measured temperatures inside the
RU and TU (
TU and RU Temp in Measurements menu), which are offset
corrected to be approximately equal to the ambient temperature.
Method “Spectral” (only for temperature) sets the gas temperature equal to the
temperature measured spectroscopically. This method is only applicable for
instruments measuring gas temperature like the O
2
+Temperature monitor.
Method “Serial”: Pressure and temperature input through RS-232 or Ethernet
connector (requires special data packet, contact SERVOMEX for details).