Surge Arrester Fed by a Breaker

[Electriman]

Greetings,

Has any body seen that a surge arrester (TVSS) in switchboard is fed by a breaker? Is it common? if so how do I need to size the breaker? I had seen them directly connected to main bus without a breaker in between.

 

[LarryFine]

Every one I've seen came with instructions to use a breaker, and mentioned the breaker size range.

What code-compliant connection allows direct connection, and how did you select conductor size?

 

[topgone]

Greetings,

Has any body seen that a surge arrester (TVSS) in switchboard is fed by a breaker? Is it common? if so how do I need to size the breaker? I had seen them directly connected to main bus without a breaker in between.

Breaker size is determined by the size of wire connecting the TVSS. Breakers are used as disconnect when servicing.

 

[Electriman]

Every one I've seen came with instructions to use a breaker, and mentioned the breaker size range.

What code-compliant connection allows direct connection, and how did you select conductor size?

Thanks. I had seen it directly connected to bus. I was just wondering which one is code compliant. Thanks

 

[qcroanoke]

Article 285 part III covers connecting SPD's

 

[petersonra]

not all SPDs require OCPD. Some have it built into the device itself.

also breaker size is determined not by the wire size on the SPD but by the manufacturer's instructions.

also TVSS and surge suppressor are older terminology and no longer in the code.

there still are such things as lightning arrestors but they are different animals.