How to avoid Spark at relay contact ?

[binu G]

hi,
can any one suggest a solution for avoiding the spark at the relay contact for a AC inductor load ?

Thanks
Binu G

 

[dipal_z]

As far as i know you can prevent it by adding a capacitor across relay contacts but i don't have enough information about selecting its value.

Same technique is used in florescent tube light starters as well.

 

[IanP]

B) If you are using a relay to switch an AC-powered inductive load, put a
varistor in parallel with the load. The varistor voltage rating should be about
1.5 times the peak-to-peak steady-state voltage of the load.
C) Relays switching an inductive load may require a capacitor placed across
their contacts. 0.1ufd to 1.0ufd is a good starting point. If the relays are
switching an AC load, place a 100 ohm resistor in series with the capacitor.

Quoted from: **broken link removed**

Regards,
IanP

 

[hr_rezaee]

you must use a flywheel (protection) diode.
see power electronic books.

 

[Davood Amerion]

Use snabber :
connect (0.1uF-1.0uF series with 10-100 ohm) parallel with load or relay contacts.

 

[myacirkhan2]

should i connect capacitor and resistor on both phase and neutral ?

and it is necessary to use both neutral and phase through relay or only phase?

pls help

 

[kabiru]

You can connect it on the load to your relay contact.

 

[Slammer]

Snubber (R-C) is OK for most cases.
You can get better results with a transil or varistor across contacts.