Furniture Systems

[Dustin Foelber]

I have a question in regards to prewired furniture systems. Typically all furniture whips come out with a similar 8 wire configuration. 2 Grounds 2 Nuetrals 4 Hots.
It is common practice for us to combine the Regular and IG grounds, nuetrals, phase conductors, etc when there is only a few circuits routed to 2-3 cubicles, No IG, etc.
Is this a code violation? Are you required to run all conductor to every furniture feed regardless of number of cubicles.

Any input is much appreciated. Thanks Gents.

 

[david]

I have a question in regards to prewired furniture systems. Typically all furniture whips come out with a similar 8 wire configuration. 2 Grounds 2 Nuetrals 4 Hots.
It is common practice for us to combine the Regular and IG grounds, nuetrals, phase conductors, etc when there is only a few circuits routed to 2-3 cubicles, No IG, etc.
Is this a code violation? Are you required to run all conductor to every furniture feed regardless of number of cubicles.


Any input is much appreciated. Thanks Gents.

You may be violating the 180 VA per REC. for the over all design not saying that you are.

Why would you not follow the electrical design for the furniture REC?

Also if you combine the IG equipment grounds with non IG equipment grounds are you not making the whole IG system a dirty ground?

 

[infinity]

It is common practice for us to combine the Regular and IG grounds, nuetrals, phase conductors, etc when there is only a few circuits routed to 2-3 cubicles, No IG, etc.
Is this a code violation? Are you required to run all conductor to every furniture feed regardless of number of cubicles.

No, you could feed it one circuit and splice all 4 circuits together in the splice box.

 

[Dustin Foelber]

Thanks for the feed back. We have no isolated ground for this system. Drawings do not call for one either. It is just the way the furniture whip is prewired. 8 Wire whip to each connection point. Just was not sure if this was an issue to combine these.

 

[iwire]

You may be violating the 180 VA per REC. for the over all design not saying that you are.

Why would you not follow the electrical design for the furniture REC?

Also if you combine the IG equipment grounds with non IG equipment grounds are you not making the whole IG system a dirty ground?

IMO the 180 VA rule does not apply here.

 

[jeremy.zinkofsky]

Make sure that each phase conductor that shares a common neutral has a means of disconnect that simultaneously opens per NEC rules for a multiwire branch circuit I.E breaker handle tie, 2-pole breaker, etc.

 

[GoldDigger]

Some furniture manufacturers explicitly identify one hot wire (phase line) as intended for computer connections and the second neutral wire is marked and identified to be used in conjunction with that one ungrounded lead. The stated justification for this is that computers form highly non-linear loads. (That was true once, but is not necessarily true anymore. In a typical cubicle system there is not much in the way of expected load other than computers and heaters.)
The receptacles actually plugged into the furniture bussing system enforce this rule.

 

[iwire]

In the past I used to do a lot of office building work. These furniture systems have many different circuit options. I have worked with them that have had one to six circuits to supply.

But how you supply them is up to the installer or engineer. If we could see it is a group of four cubes we know it does not need six circuits so we tie them together as appropriate.

 

[iwire]

Some furniture manufacturers explicitly identify one hot wire (phase line) as intended for computer connections and the second neutral wire is marked and identified to be used in conjunction with that one ungrounded lead. The stated justification for this is that computers form highly non-linear loads. (That was true once, but is not necessarily true anymore. In a typical cubicle system there is not much in the way of expected load other than computers and heaters.)
The receptacles actually plugged into the furniture bussing system enforce this rule.

To add to that often the neutral will be 10 AWG while all other conductors 12 AWG