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2. Precautions on wiring
Precautions on wiring are described below. Observe them to maintain safety and reliability.
1) Feed power source
For the power source for the unit, use the single-phase power source with stable voltage and without
waveform strain to prevent malfunctions.
(1) Switch and overcurrent protective device
Add a switch and overcurrent protective device (250V, 3A) to the feed power source
to prevent an electric shock on wiring. The unit has no replaceable fuse.
(2) Connect after the power source is turned OFF
When performing power and input/output wiring, make sure to turn OFF the feed
power source to prevent an electric shock.
2) Separate from strong power circuits
For input/output wiring, avoid adjacency or parallel with strong power circuits such as power lines. Separate
50cm or more for adjacency or parallel.
3) Separate thermocouple input from heat sources.
To reduce reference junction compensation errors for thermocouple input, especially separate terminals
from heat sources (heating body). Also, avoid radiation such as direct sunlight.
4) Separate from noise sources.
Separate from noise sources as much as possible. Unexpected troubles may occur. If separation from
noise sources is disabled, implement countermeasures.
Main source
Countermeasures
Electromagnetic switch or others
Power line with distortion of wave
Inverter
Thyristor regulator
Insert noise filters between power source and input/output
terminals. CR filters are used in many cases.
!
Warning