What should be done about surge-absorbing circuits for AC-load Solid-state Relays?Last Updated: September 19, 2018
Measures against AC Switching Solid-state Relay Output Noise Surges
2.The following models have a built-in surge-absorbing varistor:
G3NA, G3S, G3PA, G3PB, G3NE, G3J, G3NH, G9H, G3DZ (some models), G3RZ, G3FM
3.Be sure to take measures against surge when switching an inductive load with an Solid-state Relay that does not have a built-in surge-absorbing element. (Refer to the following figure.)
Note:A separate varistor with a surge resistance higher than the built-in varistor must be mounted externally if influence is possible from noise that is not completely absorbed by the built-in varistor (surge resistance: 700 to 1000 A).
Select a surge-absorbing element that meets the conditions in the following table.
|Voltage||Varistor voltage||Surge resistance|
|100 to 120VAC||240 to 270 V||1,000 A min.|
|200 to 240VAC||440 to 470 V|
|380 to 480VAC||820 to 1,000 V|