GRAPHTEC MT100 - Noise Countermeasures

2-21
Checks and Preparation
2.14 Noise Countermeasures
Be sure to connect the chassis GND of the object to be measured.
It may become effective by ensuring that the chassis GND wire of the measurement object is
connected to a good ground.
Devicetobemeasured
Z 3
MT100
Z 1 Z 2
Thermocouples
＋
−
Vin
R1
R2
Inputterminal
Connect the signal chassis GND and the measurement device chassis ground.
Use a short, thick lead to connect the chassis GND of the measurement object to the MC100’
chassis GND. It will become even more effective if the ground potentials are the same.
Measurement device chassis MT100
GND GND
Connecttoground(protectiveground)
Connecttothechassistobemeasured
(functionalground)
Noise Countermeasure Examples
If the measured values fluctuate due to an external noise source, try taking the following
countermeasures (effects may vary according to the type of noise source).
Ex.1: Connect MT100's GND to ground.
Ex.2: Connect MT100's GND to measured object's GND.
Ex.3: In the AMP settings, set filter to value other than OFF.
Ex.4: Set a sampling interval that enables MT100's digital filter feature (500 ms or above).
In the [OTHR] menu, set the frequency of the AC line used.
Refer to page 3-39 for details.