Lighting Switch/ Branch Circuits

[Designer69]

Is it general practice that all fixtures controlled by a certain lighting switch must be on a certain circuit?

What I mean is... Is it ok to have 1 branch circuit that supplies say 14 Light Fixtures (208, 2P) but 7 of those fixtures are controlled by Switch A and the other 7 controlled by Switch B?

Or must they all be controlled by 1 switch only?

This is for an auto repair type facility.

Thank You for your help!

 

[ActionDave]

....Or must they all be controlled by 1 switch only?

No

 

[infinity]

You could use a separate switch for each light if you like.

 

[Designer69]

Thanks, how does the electrician typically wire this... multi connections at the circuit breaker then run one feed to Switch A and its light fixtures then run the other feed to Switch B and its light fixtures?

or run one feed only from the CB and use field JB's to split out the feeds to the 2 switches?

 

[Little Bill]

Thanks, how does the electrician typically wire this... multi connections at the circuit breaker then run one feed to Switch A and its light fixtures then run the other feed to Switch B and its light fixtures?

or run one feed only from the CB and use field JB's to split out the feeds to the 2 switches?

Normally the ladder but there may be scenarios that could change that such as location of switch(es) or location of lights in relationship, type of lights, etc.

 

[electrofelon]

I recently had a situation where one room had more than one 20A circuit worth of lights. The plans were quite non specific and I knew they wouldnt care, so I just divided them into two zones with a circuit for each. One could use a double pole switch (possibly hard to find a switch whose instructions allow two diff circuits) or a contactor if you really have to have one switch.

 

[JFletcher]

Thanks, how does the electrician typically wire this... multi connections at the circuit breaker then run one feed to Switch A and its light fixtures then run the other feed to Switch B and its light fixtures?

or run one feed only from the CB and use field JB's to split out the feeds to the 2 switches?

Typically, one would run a single feed from the breaker to the light switch box, then run a hot jumper across as many switches as needed, one through eight, then connect all of the lighting circuits hot wires to the other pole on the switch, with all neutrals and grounds tied together.

A better installation in my opinion is a separate Hotwire pigtail to each switch, although I don't know of any wire nuts or pushin connections that can accept 9 wires (1 hot from the breaker, 8 switch feeds). Fortunately 8 gang switch boxes are fairly uncommon, and there is nothing wrong with using two wire nuts or Wago connectors.

You could even have three or more switches controlling one light or one light Bank, with a three-way switch at the beginning and end, and as many 4-way switches as desired or needed in between.

Relays, lighting contactors, and programmable switches are other options. Occupancy sensors, photocells, motion detectors, and time clocks can be added into the circuits as well.