TVSS

[sam34]

I'm working on a project that required a TVSS to be installed in a 2000A/208V/3phase/4W switchgear. I'm using 6-circuit breakers (NO main), and one of those CB I'm using for the TVSS. I have been told to consider the TVSS as a load which will take one main breaker. My understanding the TVSS is not a load,please if someone will comment on this issue.
Thank you,

Sam

 

[charlie b]

Re: TVSS

I think the NEC is unclear on this issue. The Washington State Administrative Code (WAC) made it clear for its purposes by stating that you could have six disconnects in addition to having a disconnect that serves the TVSS.

 

[cpal]

Re: TVSS

Are you asking if the disconnect for the TVSS is considered as one of the 6 limited by 230. 72


Charlie P

 

[al hildenbrand]

Re: TVSS

In the 2005 NEC, the last sentence of:
230.71 Maximum Number of Disconnects.
(A) General.
has been tweaked to include TVSS.

It now reads:

For the purpose of this section, disconnecting means used solely for power monitoring equipment, transient voltage surge suppressors, or the control circuit of the ground-fault protection system or power-operable service disconnecting means, installed as part of the listed equipment, shall not be considered a service disconnecting means.

 

[sam34]

Re: TVSS

Thank you all for replying. It looks like NEC/2005 answered it clear that TVSS doesn't consider the TVSS as one of the 6-limited disc. means. But it looks like I have to check with AHJ to see what they have got to say.Thanks again