IAI America ERC2 User Manual
Page 33

1. Overview
14
Diode
(2) Noise sources and elimination
Among the numerous noise sources, solenoid valves, magnet switches and relays are of particular concern
when building a system. Noise from these sources can be eliminated by implementing the measures
specified below.
[1] AC solenoid valves, magnet switches and relays
Measure: Install a surge absorber in parallel with the coil.
[2] DC solenoid valves, magnet switches and relays
Measure: Install a diode in parallel with the coil. Determine the diode capacity in accordance with the load
capacity.
In a DC circuit, connecting a diode in reverse polarity will damage the
diode, internal parts of the controller and/or DC power supply, so exercise
due caution.
m
Point
Install a surge absorber to each coil over a minimum wiring
length.
Installing a surge absorber to the terminal block or other part
will be less effective because of a longer distance from the coil.
Surge absorber