Control circuit tap on line side of breaker

[MechEdetour]

Good morning,

I think I have this one squared away, but want to "check-in" anyways.

Working with a customer that would like to have a light for trip/overload indication. In a combo motor starter this is easy to accomplish considering we tap off the load side of the breaker for the control circuit, and then use the alarm contact on the overload relay to provide indication. During an overload, the control circuit is still live, and we can power the indicating light.

Now, we have feeder breakers we are also providing. Customer is requesting that we provide indication for breaker trip. They're requesting a CPT within the enclosure to power the indicating light. Note that these are 3P 480V breakers, and 480-120 CPT are being used throughout. We initially stated that customer will need to provide external power to feed the indicating light since the 120V control circuit will de-energize when the breaker trips. They came back and said to tap off the load side of the breaker. My issue here is the load side conductors are taps, and per 240.21 you "can't tap a tap."

Is my reasoning sound here? If the load side conductors were feeders I wouldn't have an issue, but they're not...

If I am right, does anyone have any other ideas in terms of how an indicating light can be powered within an enclosure without an external source, with a breaker that is being fed by tap conductors? Doesn't seem like there are any other options aside from feeding it from an external source...

Thanks in advance, hope my explanation isn't confusing.

 

[kwired]

Good morning,

I think I have this one squared away, but want to "check-in" anyways.

Working with a customer that would like to have a light for trip/overload indication. In a combo motor starter this is easy to accomplish considering we tap off the load side of the breaker for the control circuit, and then use the alarm contact on the overload relay to provide indication. During an overload, the control circuit is still live, and we can power the indicating light.

Now, we have feeder breakers we are also providing. Customer is requesting that we provide indication for breaker trip. They're requesting a CPT within the enclosure to power the indicating light. Note that these are 3P 480V breakers, and 480-120 CPT are being used throughout. We initially stated that customer will need to provide external power to feed the indicating light since the 120V control circuit will de-energize when the breaker trips. They came back and said to tap off the load side of the breaker. My issue here is the load side conductors are taps, and per 240.21 you "can't tap a tap."

Is my reasoning sound here? If the load side conductors were feeders I wouldn't have an issue, but they're not...

If I am right, does anyone have any other ideas in terms of how an indicating light can be powered within an enclosure without an external source, with a breaker that is being fed by tap conductors? Doesn't seem like there are any other options aside from feeding it from an external source...

Thanks in advance, hope my explanation isn't confusing.

Assuming you are talking about either a combination starter or a MCC bucket - load side of switch/breaker is ordinarily the branch circuit conductors not a feeder tap.

But I don't see how you are going to do this and be able to say everything inside is dead when the switch is open either. Use of low energy external source for said indication system could work though.

 

[MechEdetour]

Assuming you are talking about either a combination starter or a MCC bucket - load side of switch/breaker is ordinarily the branch circuit conductors not a feeder tap.

But I don't see how you are going to do this and be able to say everything inside is dead when the switch is open either. Use of low energy external source for said indication system could work though.

Yes, for the combo starter I agree that they're branch circuit conductors. No issue with that one.

The equipment we're trying to figure out the indication for however could be a feeder breaker or a branch breaker. We're providing an enclosure with a 3P 480V breaker. The load side can either terminate at another OCPD rendering them feeder conductors, or they can be branch conductors similar to the combo starter you mention above. Not sure how it will be used in the field... Point is, on the line side it's a feeder tap. And customer is asking us to tap off the feeder tap that is feeding the breaker in question, to power the indicating light (sorry that's a mouthful).

Your last statement alludes me to what I think as well. Ultimately there will need to be an external source to accomplish this.

 

[MechEdetour]

Just realized I made a silly error explaining the context of my question... Hence why everyone reading it was probably thrown off too. What I meant to say was "line side" in my explanation, not "load side." Even in the response above I should've realized this error because as stated, they would in fact be branch conductors on the load side... I corrected my "load" references to "line" references below. Should make more sense now.

And now that it's corrected, and other comments or is there no other way?

Good morning,

I think I have this one squared away, but want to "check-in" anyways.

Working with a customer that would like to have a light for trip/overload indication. In a combo motor starter this is easy to accomplish considering we tap off the load side of the breaker for the control circuit, and then use the alarm contact on the overload relay to provide indication. During an overload, the control circuit is still live, and we can power the indicating light.

Now, we have feeder breakers we are also providing. Customer is requesting that we provide indication for breaker trip. They're requesting a CPT within the enclosure to power the indicating light. Note that these are 3P 480V breakers, and 480-120 CPT are being used throughout. We initially stated that customer will need to provide external power to feed the indicating light since the 120V control circuit will de-energize when the breaker trips. They came back and said to tap off the load side of the breaker. My issue here is the line side conductors are taps, and per 240.21 you "can't tap a tap."

Is my reasoning sound here? If the line side conductors were feeders I wouldn't have an issue, but they're not...

If I am right, does anyone have any other ideas in terms of how an indicating light can be powered within an enclosure without an external source, with a breaker that is being fed by tap conductors? Doesn't seem like there are any other options aside from feeding it from an external source...

Thanks in advance, hope my explanation isn't confusing.

Edit: I also have Mike Holt's "Understanding the NEC" book and he has plenty of figures that seem to explain this as well. In one of the figures in the book he has tap conductors tapping off of other taps and he highlights it and says it is an NEC violation. If I were to explain why this is a violation I would say that 240.21(B) says "Conductors shall be permitted to be tapped, without overcurrent protection at the tap, to a feeder as specified in 240.21(B)(1) through (B)(5). The provisions of 240.4(B) shall not be permitted for tap conductors." "... to a feeder" indicates to me that it has to be a feeder to be tapped, and not a tap.

 

[jap]

Let the pilot light "not" being illuminated indicate that the breaker has tripped.

A pilot light used in this instance is not a fool proof method seeing as how the fuse in the control transformer could blow, or, the lamp in the pilot light could simply burn out and give you a false indication that the breaker has tripped when it actually hasn't.


JAP>

 

[MechEdetour]

Let the pilot light "not" being illuminated indicate that the breaker has tripped.

A pilot light used in this instance is not a fool proof method seeing as how the fuse in the control transformer could blow, or, the lamp in the pilot light could simply burn out and give you a false indication that the breaker has tripped when it actually hasn't.


JAP>

This part doesn't jive with your "not" being illuminated comment.

But to add to this, the whole request is red PL for "ON", green PL for "OFF", and amber PL for "TRIP." There is no shortage of indication being requested here. Oh, and also a white PL for "CPT POWER" that indicates CPT health...