Bonding Bushings on eccentric KO's

[Carultch]

this question just came up on my job so I searched and found this thread.

So over 250v with eccentric requires a bond bushing right?

my example is a 480v, 30a service disconnect feeding an exhaust fan.

 

[infinity]

this question just came up on my job so I searched and found this thread.

So over 250v with eccentric requires a bond bushing right?

my example is a 480v, 30a service disconnect feeding an exhaust fan.

Yes, disconnect switches with concentric or eccentric KO's are not listed like most boxes are.

 

[Carultch]

Yes, disconnect switches with concentric or eccentric KO's are not listed like most boxes are.

Both concentric and eccentric KO's remaining require bonding bushings, when the system is >250V to ground nominal, unless otherwise listed for bonding at the higher voltages. Or other substantial bonding means to bypass the path through the knockout rings, such as bonding hubs with jumpers or bonding locknuts with jumpers

 

[infinity]

Both concentric and eccentric KO's remaining require bonding bushings, when the system is >250V to ground nominal, unless otherwise listed for bonding at the higher voltages. Or other substantial bonding means to bypass the path through the knockout rings, such as bonding hubs with jumpers or bonding locknuts with jumpers

That's pretty much what I said no? Most boxes are listed for bonding over 250 volts, disconnect switches aren't.

 

[hacim23]

Yes, disconnect switches with concentric or eccentric KO's are not listed like most boxes are.

How do you find the UL listing? Ive seen 'UL Listed' on things but how would you know referring to grounding/bonding.

 

[infinity]

How do you find the UL listing? Ive seen 'UL Listed' on things but how would you know referring to grounding/bonding.

You can start with the UL "white book".

https://www.google.com/url?sa=t&rct...5UKoZVKlEjf6ke8oA&sig2=bn8qyLcs3sifDueBgsR0pQ