options for Switched neutral breakers

[Weslondon]

I am having a serious problem finding Square D QO switched neutral breakers for several gas station e-stop jobs. We are converting quite a few stations over to have e-stops and trying to hold these jobs off any further is creating issues. Any other suggestions in lieu of switched neutral breakers?

 

[synchro]

Would it be compliant to have a 3-phase panel with neutral on say, the B-phase bus, and then use 2 and 3-pole breakers for 120V and 240V single-phase circuits, respectively?

 

[JGinIndy]

Would it be compliant to have a 3-phase panel with neutral on say, the B-phase bus, and then use 2 and 3-pole breakers for 120V and 240V single-phase circuits, respectively?

I’m confused?

 

[Buck Parrish]

Would it be compliant to have a 3-phase panel with neutral on say, the B-phase bus, and then use 2 and 3-pole breakers for 120V and 240V single-phase circuits, respectively?

No, If so we'd all so something similar to that. 110.3 - Although it's up to the AHJ 110.2

 

[augie47]

Could you use definite purpose contactors or power relays ?

 

[ptonsparky]

Could you use definite purpose contactors or power relays ?
View attachment 2555562

Doesn‘t the circuit breaker for that branch circuit still need to disconnect all of the current carrying conductors?

 

[augie47]

I may not be reading correctly but I simply see all need to be disconnected.
(Been wrong before)

 

[hillbilly1]

I have seen three pole latching contactors breaking the hots and neutrals on a single phase pump panel.

 

[rbalex]

I endorse augie47's solution. If you read Section 514.11(A) carefully it only mentions a switch or approved means. A circuit breaker is not specifically called out at all. The specific requirement is "... to disconnect simultaneously from the source of supply, all conductors of
the circuits, including the grounded conductor, if any." Also, note not every disconnecting means in the circuit is required to perform this function, only one of them. '

 

[Flicker Index]

Oh boy. they're expensive.

QO220SWN1021 - Schneider Electric - Molded Case Circuit Breakers

Find QO220SWN1021, Molded Case Circuit Breakers by Schneider Electric at Electrical.com. All products include 2 year warranty, same day shipping.

www.widespreadsales.com

 

[wallyworld]

If sq d switched neutrals are all you are having trouble getting consider yourself lucky. I use 2 pole switches all the time. Not sure how that figures into your e stop though?

Sent from my SM-G950U using Tapatalk

 

[wwhitney]

No, If so we'd all so something similar to that. 110.3 - Although it's up to the AHJ 110.2

I don't see anything there prohibiting the use of a 3 bus panel for 120/240V plus neutral, seems like an elegant solution.

Cheers, Wayne

 

[ptonsparky]

I don't see anything there prohibiting the use of a 3 bus panel for 120/240V plus neutral, seems like an elegant solution.

Cheers, Wayne

I believe a three phase panel can be used on a grounded delta. I suspect it changes to bolt on vs snap in.

IDK if I would have the gumption to try it before a discussion with an AHJ.

 

[JGinIndy]

I am still confused. Yes I understand a switched neutral breaker. So what your saying is use a 3ph buss ( B phase not used not energized) just to allow the neutral to be able to common trip in let’s say a 3 pole breaker 208 or / 240v or a 2 pole breaker for 120v am I correct?

 

[LarryFine]

I am still confused. Yes I understand a switched neutral breaker. So what your saying is use a 3ph buss ( B phase not used not energized) just to allow the neutral to be able to common trip in let’s say a 3 pole breaker 208 or / 240v or a 2 pole breaker for 120v am I correct?

N, they're suggesting feeding a 1-phase panel's line terminals at 120v, L1 on one phase, the neutral on the other.

As if you were supplying 240v circuits without neutrals, except you'd have 120v instead of 240v.

You could bond the neutral bus and use it as an EGC bus if you like (which should help explain it.)

 

[wwhitney]

The original suggestion was to use a 3 phase panel, with one bus L1, one bus N, and one bus L2. But a single phase panel with one bus L and one bus N also works. Or two panels, one for 120V circuits on L1, and one for 120V circuits on L2.

Depends on what mixture of circuit types you need, and whether you need to balance the 120V circuits between L1 and L2 or not.

Cheers, Wayne

 

[JGinIndy]

N, they're suggesting feeding a 1-phase panel's line terminals at 120v, L1 on one phase, the neutral on the other.

As if you were supplying 240v circuits without neutrals, except you'd have 120v instead of 240v.

You could bond the neutral bus and use it as an EGC bus if you like (which should help explain it.)

Thanks

 

[LarryFine]

The original suggestion was to use a 3 phase panel, with one bus L1, one bus N, and one bus L2.

Wouldn't you end up with every third space empty, a la a high-leg panel?

 

[JGinIndy]

The original suggestion was to use a 3 phase panel, with one bus L1, one bus N, and one bus L2. But a single phase panel with one bus L and one bus N also works. Or two panels, one for 120V circuits on L1, and one for 120V circuits on L2.

Depends on what mixture of circuit types you need, and whether you need to balance the 120V circuits between L1 and L2 or not.

Cheers, Wayne

Thanks Wayne and Larry that’s what I was thinking in my head and would never have thought of doing it. Learn something new every day

 

[wwhitney]

Wouldn't you end up with every third space empty, a la a high-leg panel?

Yes, if it was supplying only switched neutral 120V circuits. But perhaps it's important to balance those loads across L1 and L2, and a 3 phase panel with empty spaces would still be more compact than two single phase panels.

Or perhaps you also need some 240V only circuits, which could use the other spaces. [6 spaces gives one L1/L2, one L1/N, and one L2/N.]

Or maybe you need some switched neutral MWBCs.

Cheers, Wayne