code question Branch circuits

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highpowered

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I cant find in the 2008 nec code if i'm allowed to run branch circuits from different sub-panals through the same conduit? I have a inverter 100min battery backup for the egress lighting. I want to switch the existing egress circuits to the inverter using the existing panel as a jbox.? Cant find If this is allowable or not? Any help will be appreciated
 
I don't think there is a problem. If the PV wiring is 120V or 12V it needs to have insulation rated as high as the highest conductor voltage in the panel.
 
Cool thanks Its a parking garage Building is fed 208y/120 The 2 panels that feed the lights are in seperate locations 208y/120. I'm moving the back 2 egress circuits to the existing inverter panel 240/120 which is next to the 2nd garage panel. im moving those 2 existing egress over to the inverter as well splicing into both panels using them as jboxes for the existing circuits. My other question is if I tie into the nuetral bar for the move is this OK? The reason for this is its a 3 wire circuit(3hots 1 nuetral) This I cant find either in nec. I've reduced the load by half on all the circuits.
I'm submitting the plan check for this as im retrofitting the flourescents to LED and the LED does not have battery backups. The im removeing 116 flourescent 22wTT t8s and installing 58 44 watt LED. All I'm going to doe is submit the circuit change to the inverter box for the emergency system.
 
You can't mix or cross connect the neutrals from the two sources. If the panel used as a junction box is only supplied from the inverter, then you could use the neutral bar for the new circuits. If the panel will still have a feed from its existing source, you cannot connect to the neutral bar.

If I read it right, you will be using an existing panel as a junction box for the revised egress circuits. The panel will then have load wires in it that are hot when the panel's main breaker is off. Some inspectors might have a problem with that, but I don't know of a specific code prohibition. You may need a "CAUTION: FORIEGN VOLTAGE PRESENT" warning label on the panel.
 
rcwilson said:
You can't mix or cross connect the neutrals from the two sources. If the panel used as a junction box is only supplied from the inverter, then you could use the neutral bar for the new circuits. If the panel will still have a feed from its existing source, you cannot connect to the neutral bar.

If I read it right, you will be using an existing panel as a junction box for the revised egress circuits. The panel will then have load wires in it that are hot when the panel's main breaker is off. Some inspectors might have a problem with that, but I don't know of a specific code prohibition. You may need a "CAUTION: FORIEGN VOLTAGE PRESENT" warning label on the panel.
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I agree with you 100% It was weird to not find that in the code book. I like the idea of labeling the panel for safety purposes. In that panel there is only 6 circuits all are for garage lights im moving 2 to the inverter so theres 4 left. If i run a independent neutral for the emergency lights not tieing into the neutral bar but splicing inside panel disconnecting that from the bar this would be safest and inspector friendly? Source meaning subpanel sources ormain power source? If I label both panel permanatly as to where the 2 circuits are (inverter panel # 2,4) would this be better
 
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If the circuits to the egress lights are covered by Article 700, they cannot be in the same enclosure with other non-emergency circuits.
 
I agree with you 100% It was weird to not find that in the code book.
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Is this what you are looking for?

300.3(B) Conductors of the Same Circuit. All conductors of
the same circuit and, where used, the grounded conductor
and all equipment grounding conductors and bonding con-
ductors shall be contained within the same raceway, auxil-
iary gutter, cable tray, cablebus assembly, trench, cable, or
cord, unless otherwise permitted in accordance with
300.3(B)(1) through (B)(4).
 
don_resqcapt19 said:
If the circuits to the egress lights are covered by Article 700, they cannot be in the same enclosure with other non-emergency circuits.
Click to expand...

i understand i was hoping 700.9 3,4 would allow me to keep the existing podium wiring the way it is. Installing the LED system is expensive enough im afraid they wont want to upgrade their other buildings if I have to rewire the emergency system each time. According to this I will have to run a new raceway over the entire parking structure to remove the emergency lighting circuits from the rest of the general lighting inside the podium raceway.
 
highpowered said:
i understand i was hoping 700.9 3,4 would allow me to keep the existing podium wiring the way it is. Installing the LED system is expensive enough im afraid they wont want to upgrade their other buildings if I have to rewire the emergency system each time. According to this I will have to run a new raceway over the entire parking structure to remove the emergency lighting circuits from the rest of the general lighting inside the podium raceway.
Click to expand...

There is nothing in the NEC that will allow you to run the output circuits from an emergency inverter in the same conduits as the normal wiring.

I know this is a pain, we deal with it all the time. You need to find battery units for your LEDs Or run new conduits or add EBUs everywhere
 
iwire said:
There is nothing in the NEC that will allow you to run the output circuits from an emergency inverter in the same conduits as the normal wiring.

I know this is a pain, we deal with it all the time. You need to find battery units for your LEDs Or run new conduits or add EBUs everywhere
Click to expand...

EBU?? Emergency Battery Unit?
 
iwire said:
There is nothing in the NEC that will allow you to run the output circuits from an emergency inverter in the same conduits as the normal wiring.

I know this is a pain, we deal with it all the time. You need to find battery units for your LEDs Or run new conduits or add EBUs everywhere
Click to expand...

Unfortunatly the battery systems for LEDs will cost the same as running the new wires. They run 2-300 a pop and even if I wanted to do that they wont be available for 6-9months. Add EBUs everywhere?
 
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