seperation of lighting and equipment

[e57]

Any one else do this - or is it just me???

Separate panels for equipment and lighting in larger homes of the >10ksq' range. IMO it just seems that voltage drop due to some of the larger equipment motor starting, combined with heavier lighting loads is a recipe for dimming lights everytime the AC or pool pump kicks on.

 

[cpal]

I don't think Vd is a problemunless the length of the feeder is exceptional, but that is a design issue. My concern is the use of 310.15 B 6 for the panels. How are the Feeder conductors selected B 6 or Table 16???

 

[e57]

I'm talkin bout voltage drop due to inrush current - not distance. But good point - the smaller conductor of B6 will be affected by in-rush more. But not much more than 16 - I think....

EG - I have a 600a main to a 5 lbs bag with 10 lbs stuffed in it... 200a of which is lighting, another 200+ is elevator (minimal in this case), mechanical (lots of large motors), and cooking equipment (Several ovens).

What I want, and often do - is seperate these so when the AC kicks on - it is not as evident (dimming effect from in-rush) as if it were if coming from the same feeder.

Just been working with new people lately, and wondering if I was the only cat who seperated them?

 

[Jim W in Tampa]

Its fine if they are paying for it but not needed

 

[LarryFine]

I do like doing the same thing on a smaller scale. I prefer to keep receptacle and lighting circuits separate, but I haven't yet had the need to separate loads panel by panel. I wouldn't hesitate to do so if the need presented itself.

 

[benaround]

I don't think Vd is a problemunless the length of the feeder is exceptional, but that is a design issue. My concern is the use of 310.15 B 6 for the panels. How are the Feeder conductors selected B 6 or Table 16???

cpal, B 6, can not be used for "feeders" , unless it is the main power feeder

for the dwelling. The main power feeder carries the complete load, just the

same as service conductors. B 6, can't be used after the service panel.

 

[e57]

Debate about that.... (Only got the 02 on hand - not sure if it changed???)

For application of this section, the main power feeder shall be the feeder(s) between the main disconnect and the lighting and appliance branch-circuit panelboard(s)

B6 can be used for multiple feederS to multiple panelS. Granted - after that all else seems to fall outside that definition.

Anyway not to wander too far off topic....

Does anyone else seperate them as a rule of thumb?

I just hate this type of question from HO's - and I never get it when I do seperate them....
HO: "When I turn the oven on - there is a slight dim to the light... Is that normal?"

 

[Dennis Alwon]

Debate about that.... (Only got the 02 on hand - not sure if it changed???)
B6 can be used for multiple feederS to multiple panelS. Granted - after that all else seems to fall outside that definition.

The 08 has clarified this. One feeder. Besides if you separate your equipment from the lighting and recep. loads then you are really changing the diversity of the load which is what T310.15(B)(6) is all about.

Here is the 08. The bold is the shaded area in the 08

Art. 310.15(B)(6) 120/240-Volt, 3-Wire, Single-Phase Dwelling Services and Feeders. For individual dwelling units of one-family, two-family, and multifamily dwellings, conductors, as listed in Table 310.15(B)(6), shall be permitted as 120/240-volt, 3-wire, single-phase service-entrance conductors, service-lateral conductors, and feeder conductors that serve as the main power feeder to each dwelling unit and are installed in raceway or cable with or without an equipment grounding conductor. For application of this section, the main power feeder shall be the feeder between the main disconnect and the panelboard that supplies, either by branch circuits or by feeders, or both, all loads that are part or associated with the dwelling unit. The feeder conductors to a dwelling unit shall not be required to have an allowable ampacity rating greater than their service-entrance conductors. The grounded conductor shall be permitted to be smaller than the ungrounded conductors, provided the requirements of 215.2, 220.61, and 230.42 are met.

 

[supermanhicks]

I try to do this but does it really matter if your panelboards are within the same room being fed by the same switchboard? The "electrical distance" between them is still almost nothing despite being put on a nearby panel.

 

[acrwc10]

Debate about that.... (Only got the 02 on hand - not sure if it changed???)
B6 can be used for multiple feederS to multiple panelS. Granted - after that all else seems to fall outside that definition.

Anyway not to wander too far off topic....

Does anyone else separate them as a rule of thumb?
I just hate this type of question from HO's - and I never get it when I do separate them....
HO: "When I turn the oven on - there is a slight dim to the light... Is that normal?"

I agree 100% with you on this. On smaller jobs I try and take large loads such as ovens, air cond. , etc. out of the main and lighting and such out of the distribution panel.
What I really hate is on remodel work when the POCO lines are to small for the inrush, and they won't do anything for you on that one. I've seen plenty of homes where the lights dim when "Joe" down the street uses a saw.

 

[e57]

Dennis (still a seperate topic) there still seems to be an "S" after feeder there implying plaural. eg all those 320/400 class panels with 2-200a main cb's with two feeders out of them....

And I really dont think it changes the load diversity all that much. You still may not have ALL the lights on, or use ALL the recepticals. Nor would you use ALL of the equipment in most cases.

I agree 100% with you on this. On smaller jobs I try and take large loads such as ovens, air cond. , etc. out of the main and lighting and such out of the distribution panel.
What I really hate is on remodel work when the POCO lines are to small for the inrush, and they won't do anything for you on that one. I've seen plenty of homes where the lights dim when "Joe" down the street uses a saw.

Yes - exactly... By-pass the lighting panels where this in-russ would be more noticable - to the main which would be larger

And I too have seen this after doing an AC unit - turned it on and the whole block dimmed. I got this 'I better get in the truck' feeling....