CBs fed from different source can be installed in same enclosure as per NEC?

T

TMMB

Senior Member
Location
EGYPT
Occupation
Electrical Manager
A lighting pole has 3 floodlights powered by a regular power source and 2 floodlights powered by another emergency power source. Is it permissible to combine the main circuits breakers for both power source and the outgoing circuit breakers in same fuse box?
Is it possible to install circuit breakers for two different sources in the same fuse box
 
When you say, "powered by another emergency power source." what does that mean? Do you have a generator, with separate breakers for normal and emergency, separate panels for normal and emergency and no batteries in your emergency lighting? If so, then not only can you NOT combine the breakers, the wiring needs to be separated by a raceway per article 700
 
we have 2 power supply one normal and the other by UPS, so my Q is , it is possible to have 2 different feeders from 2 different power supply in the same enclosure?
 
TMMB said:
we have 2 power supply one normal and the other by UPS, so my Q is , it is possible to have 2 different feeders from 2 different power supply in the same enclosure?
Click to expand...
See 700.10(B)
Is the UPS actually an emergency system or is it optional standby?
 
we have 2 power supply one normal and the other by UPS, so my Q is , it is possible to have 2 different feeders from 2 different power supply in the same enclosure?
roger said:
See 700.10(B)
Is the UPS actually an emergency system or is it optional standby?
Click to expand...
to keep power available always
 
TMMB said:
we have 2 power supply one normal and the other by UPS, so my Q is , it is possible to have 2 different feeders from 2 different power supply in the same enclosure?

to keep power available always
Click to expand...
But you would need to know if it's an article 700 "Emergency" system, an article 701 "Legally Required" system, or an article 702 "Optional Standby" System.
The rules are different for the type system you have. If you have an article 700 system the pole will need to meet one of the conditions of 700.10(B)
 
The panel needs needs new labeling that states there's two different /Multiple sources of power in enclosure!

(sorry no NFPA for exact reference)
 
to clarify my Q, KINDLY, REVIEW THE ATTACHED, MY CLEAR Q IS , IT IS PERMISSABLE TO INSTALL MULTIBLE C.Bs feeding from different sources, please, helping me t take deaccession
 

Attachments

  • 20241221_100007.pdf
    1.4 MB · Views: 12
This looks to me like you are cross connecting some of the breakers.

It appears the two pole breaker on the left does not have anything connected to one of its poles as well.

I would want to see a schematic.
 
petersonra said:
This looks to me like you are cross connecting some of the breakers.

It appears the two pole breaker on the left does not have anything connected to one of its poles as well.

I would want to see a schematic.
Click to expand...
kindly, find attached the required schematic
 

Attachments

  • Schematic1.pdf
    70.7 KB · Views: 8
This does not look like a US style installation.

Incidentally, the single phase supply in the schematic shows the P line connected where the E line should be.

I don't think what is in the box matches this diagram either.

In any case the diagram does clear up whether this actually depicts an emergency system as defined by the code. It just shows a UPS supply. That does not make it an emergency circuit.
 
Last edited:
petersonra said:
This does not look like a US style installation.

Incidentally, the single phase supply in the schematic shows the P line connected where the E line should be.

I don't think what is in the box matches this diagram either.

In any case the diagram does clear up whether this actually depicts an emergency system as defined by the code. It just shows a UPS supply. That does not make it an emergency circuit.
Click to expand...
Many thx for your reply, i have another Q related to double termination from the outgoing of main CB to 2 different branch CB, is it permitted or not? attached photo to clarify
 

Attachments

  • 20241221_100007.pdf
    1.5 MB · Views: 4
TMMB said:
Many thx for your reply, i have another Q related to double termination from the outgoing of main CB to 2 different branch CB, is it permitted or not? attached photo to clarify
Click to expand...
Is the terminal listed for two wires? If it is than you can attach two wires to it.
 
You must log in or register to reply here.
Top