SHIMPO DT-601CG - Manual (Page 53)

23. ABOUT NOISE PROTECTION
Refer to the following if there is problem of electronic noise.
If product has problem that is a display disapper/mis-display, Do the initialization.(Refer to P16)
Initialization makes every current set value to be reset. Record the current value prior to the initialization.
And do the following noise protection.
(1) Do not share power supply and power line directly.
When you use power line, Use isolation transformer and use secondary.
(2) Use three core shield line for sensor cord.
(3) Shorten sensor cord as much as possible.
(4) It is better not to connect machinery's ground wire with GND of meter.
(5) Use noise filter if there is a noise from power line. (Refer to following figure.)
(6) wired method of sensor cord
When the power cord passes near sensor cord, sensor cord must be wired with single.
(7) When the noise is generated around product, Use a spark killer.
Ex: Electromagnetic Contactor, Temperature Controller, Solenoid Valve, Relay, etc. )
Power Supply
Noise Filter
GND
Meter
Shorten and twist the code.
Sensor Cord
Do not wire with double.
Metal Piping
Power Line
GND
Spark Killer
Contact Actuator
P54