GRAPHTEC midi LOGGER GL240 - Noise Countermeasures

2-21
CHAPTER 2 Checks and Preparation
2.13 Noise Countermeasures
•
Be sure to connect the chassis GND of the measurement object.
It may become effective by ensuring that the chassis GND wire of the measurement object is connected
to a good ground.
Z3
GL240
Z1 Z2
+
-
Vin
R1
R2
•
Connect the signal chassis GND to the measurement device chassis ground.
Use a short, thick lead to connect the chassis GND of the measurement object to the GL240’s chassis
GND. It will become even more effective if the ground potentials are the same.
GL240
GND GND
Measurement device chassis
•
Noise countermeasures
If measured values uctuate due to extraneous noise, conduct the following countermeasures.
(Results may differ according to noise type.)
Ex 1 : Connect the GL240’s GND to ground.
Ex 2 : Connect GL240’s GND to measurement object’s GND.
Ex 3 : In the AMP settings menu, set lter to any setting other than “OFF”.
Ex 4 : Set the sampling interval which enables GL240’s digital lter.
Use the “OTHER” menu to set the commercial power frequency you use.
Refer to "3.4 Setting Menus" for details.