Relay Switching and contact burning

[ElecDesigner]

Anyone know if smaller relays such as this one

G6K-2F-Y DC5 | Omron Surface Mount Signal Relay, 5V dc Coil, 1A Switching Current, DPDT | RS

uk.rs-online.com

suffer from contact bounce.

Got a problem where there appear to be burn marks and deposits on one of the contacts of a relay. The only significant current that can flow on the damaged contact is just after switch TO the damaged contact (i.e. it looks like it might be being damaged during a "make"). I just wonder if contact bounce would also cause a problem with arcing. I.E. if there is contact bounce, should we adhere to the "break" specs on make as the relay is actually making and breaking a few times before settling.

 

[barry]

You say nothing about your voltage or your load, which are kind of very important pieces of information....

 

[ElecDesigner]

I thought my questions might be general enough to get a response without specifics but here goes:

Something like:
A few kHz at a couple of 100V, not driven at this point but the source is essentially a ringing complex impedance. Load is bog standard resistive.

 

[barry]

At 200V, the maximum current this can switch is about 180mA, based on the 37.5VA rating. But I would be concerned about the arcing at such a high voltage, although there is no spec for the relay contact voltage. Maybe contact the manufacturer.

 

[dick_freebird]

Every relay has some bounce, mercury wetted ones "submerge" it but mechanically it's a sprung mass and elastic collision.

Bounce may extend an arc duration but this is really more about a decent snubber to quench.

 

[cupoftea]

A few kHz at a couple of 100V,

..that relay is rated up to 60VDC, and i'm sure you shouldnt switch 100V with it, let alone at several kHz.
You should be using a semiconductor switch i think.

Most realys are rated to 24vdc max, since switching DC with relays is problematic...AC isnt too bad as it goes to zero every period. Cars still have 12VDC because of the difficulty of switching higher DC voltages with relays.

 

[barry]

..that relay is rated up to 60VDC, and i'm sure you shouldnt switch 100V with it, let alone at several kHz.
You should be using a semiconductor switch i think.

Most realys are rated to 24vdc max, since switching DC with relays is problematic...AC isnt too bad as it goes to zero every period. Cars still have 12VDC because of the difficulty of switching higher DC voltages with relays.

MOST relays are NOT rated to 24VDC max. There are plenty of relays capable of high voltage DC switching. But that's irrelevant since OP stated that it's AC.

An SSR might be MORE problematic since there's the dv/dt issue with triacs.

Cars still have 12VDC because there's really no reason to change from what's been used for 100 years, not because of "the difficulty of switching higher DC voltages". SSRs are cheap and plentiful, so relays can't be the reason there's been no change. But, again, OP is switching AC.