OCPD's For Network Connected Circuits

Status
Not open for further replies.
H

h1h2h3

Member
Location
MA
Hi,

Doing a tenant build-out in an office building and the plans call for my power circuits (non-lighting) to be grouped as networks (one neutral for three hots each on a different phase.) Ive always just marked the neutral with the shared circuit numbers on them and then landed each hot on its own breaker. Today at work one of my co-workers told me that it is now a code requirement to land networks on 3 pole breakers so that all lines will break simultaneously and interrupt all current through the shared neutral. In a way this makes sense and in another it seems kind of dumb. Ive always thought that the only instance in which i had to use a multi-pole breakers was when my ungrounded conductors landed on the same yoke or on the same terminal block ie: multi-circuit track or wye connected 3 phase equipment. Can someone please clarify this for me? Thank you.
 
h1h2h3 said:
Hi,

Doing a tenant build-out in an office building and the plans call for my power circuits (non-lighting) to be grouped as networks (one neutral for three hots each on a different phase.) Ive always just marked the neutral with the shared circuit numbers on them and then landed each hot on its own breaker. Today at work one of my co-workers told me that it is now a code requirement to land networks on 3 pole breakers so that all lines will break simultaneously and interrupt all current through the shared neutral. In a way this makes sense and in another it seems kind of dumb. Ive always thought that the only instance in which i had to use a multi-pole breakers was when my ungrounded conductors landed on the same yoke or on the same terminal block ie: multi-circuit track or wye connected 3 phase equipment. Can someone please clarify this for me? Thank you.
Click to expand...

You on 2005 or 2008 NEC? Big difference.
 
Is that a serious question?.....The year is 2010 so 2008 nec is what i would be using. Ive honestly never heard of that before. So could you please give me a serious answer? I would look it up but i dont have my NEC handy. Thank You
 
h1h2h3 said:
Is that a serious question?.....The year is 2010 so 2008 nec is what i would be using. Ive honestly never heard of that before. So could you please give me a serious answer? I would look it up but i dont have my NEC handy. Thank You
Click to expand...

Sorry I am on 2005!

210.4 Multiwire Branch Circuits.

(B) Disconnecting Means. Each multiwire branch circuit
shall be provided with a means that will simultaneously
disconnect all ungrounded conductors at the point where
the branch circuit originates.

Your lighting and rec. circuits must follow this reference.

You can use a three pole handle tie, if it exists, or a three pole breaker.
 
Last edited:
h1h2h3 said:
Is that a serious question?.....The year is 2010 so 2008 nec is what i would be using. Ive honestly never heard of that before. So could you please give me a serious answer? I would look it up but i dont have my NEC handy. Thank You
Click to expand...
It is a very serious question!!! Local jurisdictions do not always adopt the most recent NEC. There are areas working off the 2002 or even earlier codes. In this case there was a change between the 2005 and 2008 codes and we need to know what code you are under to answer the question.
 
don_resqcapt19 said:
It is a very serious question!!! Local jurisdictions do not always adopt the most recent NEC. There are areas working off the 2002 or even earlier codes. In this case there was a change between the 2005 and 2008 codes and we need to know what code you are under to answer the question.
Click to expand...

What Don said.

jumper said:
Sorry I am on 2005!

210.4 Multiwire Branch Circuits.

(B) Disconnecting Means. Each multiwire branch circuit
shall be provided with a means that will simultaneously
disconnect all ungrounded conductors at the point where
the branch circuit originates.

Your lighting and rec. circuits must follow this reference.

You can use a three pole handle tie, if it exists, or a three pole breaker.
Click to expand...

Derek is slow:D

Also 210.4 D will come into play
 
jumper said:
You can use a three pole handle tie, if it exists, or a three pole breaker.
Click to expand...

My preference is for the tie handle (if such an animal exists for 3P) because upon a fault the tie handle will allow individual pole tripping but it won't necessary trip/disconnect the other poles. A three pole breaker would disconnect all poles causing more distruption than necessary.

Unfortunately to reset said fault the breaker must be thrown off and then back on. While this causes some disruption, its not as bad at a 3P CB.,

Jason
 
don_resqcapt19 said:
It is a very serious question!!! Local jurisdictions do not always adopt the most recent NEC. There are areas working off the 2002 or even earlier codes. In this case there was a change between the 2005 and 2008 codes and we need to know what code you are under to answer the question.
Click to expand...


Yep CA is still on 2005 NEC

~Matt
 
Status
Not open for further replies.
Top