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I want a 7th handle in my service! Deal with it!

Merry Christmas
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George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
I needed to throw a little pizzazz in the title, this niche of the forum doesn't move much. :D

Situation: We have a service. A big one. It has six breakers installed (600, 400, 200, 200, 200, 200). The one-line shows a TVSS connected directly to the service busses and gives a part number.

Problem: The TVSS requires installation on a 30A circuit breaker, per it's instructions. Failure to do so voids the warranty, and also violates a little-known, scant-referenced code, 110.3(B).

There are spaces available in the MDP for more breakers.

What would you do? :)
 

ramsy

Roger Ruhle dba NoFixNoPay
Location
LA basin, CA
Occupation
Service Electrician 2020 NEC
Nice trick to get the EC to pay for the right part number, which mounts to the service, after the bid was partially based on that little shiznit part.
 

iwire

Moderator
Staff member
Location
Massachusetts
Take over one of the 200 amp breakers, install a 200 amp MLO feed through panel right beside the existing service fed from that breaker. Tie the original 200 amp feeder to the 'other' lugs on the feed through panel.

Add a 30 amp breaker to that panel to supply the TVSS

OR

Simple fill out an RFI and put this problem back on the person that created it in the first place.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
I don't see a problem. Just put the 30 amp breaker in and connect the TVSS.
230.71 Maximum Number of Disconnects
(A) General The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception Nos. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, or a combination of not more than six switches and sets of circuit breakers, mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. There shall be not more than six sets of disconnects per service grouped in any one location. 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.
Don

edited to fix quote
 
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iwire

Moderator
Staff member
Location
Massachusetts
Serves me right for not looking at the 2005.
icon11.gif


My 2002 does not include TVSS in the list.
 

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
don_resqcapt19 said:
I don't see a problem. Just put the 30 amp breaker in and connect the TVSS.
Don, I felt the same way, but the last sentence of the section troubles me.

...installed as part of the listed equipment...
What exactly does that mean?

The service's components are listed, from Square D.
The TVSS is listed, from Liebert.

This section does not mean that the service and TVSS have to be listed together to get a 7th handle, does it? That's what is concerning me at this point.

Thanks for all the replies. :)
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Semi-Retired Electrical Engineer
No worries, mate. It means that the seventh handle has to have been installed as part of the listed service equipment. The subject of that last sentence is "means," and it is the (disconnecting) means that has to be installed as part of the listed equipment.
 

rcarroll

Senior Member
ramsy said:
Nice trick to get the EC to pay for the right part number, which mounts to the service, after the bid was partially based on that little shiznit part.
Shiznit? That made me laugh. I now have a new word to use somewhere. Thanks. Ron
 

George Stolz

Moderator
Staff member
Location
Windsor, CO NEC: 2017
Occupation
Service Manager
Thanks, Charlie, that makes sense.

What's up Ron? Don't listen to much Snoop Dogg? Just be careful, "foshizzle my nizzle" does not mean "For sure, my neighbor. :D
 
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