Elcon HiD 2000 Series, User Instruction Manual

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9.2.3.4 TC Calibrator with auto internal RJ compensation Calibration
As in paragraph 9.2.3.3 above, no signal correction is necessary since the calibrator internally compensates for its
Reference Junction as well as the instrument.
9.2.3.5 TC Calibrator with auto remote RJ compensation Calibration
As in paragraph 9.2.3.4 above, no signal correction is necessary since the calibrator has no the thermoelectric
junctions and compensates for the emission of the converters compensating circuit.
All the configurations seen are equally useful but configuration given in paragraph 9.2.3.3 is the most accurate and
easy to handle.
Configuration 9.2.3.1 is the simplest to set-up but less accurate. It is difficult to exactly track input terminal
temperature and its fluctuations.
Note that in configuration 9.2.3.1 and in configuration 9.2.3.2 the Reference Junction potential subtraction
becomes a sum of values with a negative sign if the calibrating temperature [i.e. Vt(L)] is below zero.
After noting these necessary consideration on how to generate the calibration signals, the calibration check follows
the procedure:
Connect the TC Calibrator at the input terminals of the unit and the multimeter at the output terminals (current or
voltage mode dependent to the output type). Allow five minutes for warm-up the unit, then set the calibrator at low
end of scale signal and check the output value. It should also be at low end of scale. Adjust if necessary, ZERO
trimmer of the relevant channel.
Set the calibrator for full scale value, check the output value that must also be at full scale and adjust, if
necessary, the SPAN trimmer of the relevant channel.
Return to the low end of scale and check for shifting of calibrated value. If necessary re-adjust the output value
until it comply with the specified accuracy.
If a burnout feature is specified, open the measuring line and check that the output goes beyond full scale for UP
SCALE burnout or below low end of scale for DOWN SCALE burnout.
9.2.4 mV Input Range Calibration
Connect the mV Calibrator at the input terminals of the unit and the multimeter at the output terminals (current or
voltage mode dependent to the output type). Allow five minutes for warm-up the unit, then set the calibrator at low
end of scale signal and check the output value. It should also be at low end of scale. Adjust if necessary, ZERO
trimmer of the relevant channel.
Set the calibrator for full scale value, check the output value that must also be at full scale and adjust, if
necessary, the SPAN trimmer of the relevant channel.
Return to the low end of scale and check for shifting of calibrated value. If necessary re-adjust the output value
until it comply with the specified accuracy.