4 pole mccb

[lewlec]

Hi all

just wondering if anyone knows if it would be possible to feed two single phase supplies through a 4 pole mccb?

thanks
gary

 

[Marvo]

Why not just use 2 x SP&N breakers?

 

[lewlec]

Hi

i was wanting 1 point of isolation

regards
gary

 

[Marvo]

Can you explain the layout? Won't the main MCB/isolator fulfill any requirement for single isolation point?

 

[Lighthouse Phil]

you'll be sharing the neutral, but have seen it done before

 

[Billythekid]

What are your plans for these two single phase supplies that require a single point of isolation?
As above 2 DP's, and if absolutely necessary to have single point isolation, contactors?

 

[lewlec]

Ok

i have a new supply installed which is 2 x single phase 100amp and is located remotely from the installation. Now I have a 4 core swa with separate cpc which is run from the cut out position to the installation position. I was wanting 1 point of isolation for the whole install also providing protection for the sub main. Hope this makes sense.

Gary

 

[Knobhead]

The problem will be if you use 1[SUP]st[/SUP] & 2[SUP]nd[/SUP] Ph for one of the circuits and the 3[SUP]rd[/SUP] Ph & N for the other. Only the 2[SUP]nd[/SUP] circuit will have early make late break for the neutral.

I think you can get a bridging piece for the switch dollies to link two 2 pole Telemecanique MCB’s together.

 

[Marvo]

Sorry if I'm a bit slow of the mark tonight, so there's 2 phases and a single neutral at the cutout? This isn't 180 degree split phase is it?

 

[lewlec]

Thanks tony

Didnt think it was that simple.
will have a look at the telemecanique kit

regards
gary

 

[lewlec]

Sorry if I'm a bit slow of the mark tonight, so there's 2 phases and a single neutral at the cutout? This isn't 180 degree split phase is it?

Hi marvo

no it's purely 2 x single phase supplies, wasn't involved with the supply application. Would have gone for split myself.

 

[Knobhead]

Gary,

You'd be as well phoning them, if I remember right there's a little inter-trip unit that goes between the two MCB's. It's years since I specified them, we used them in control panels.

 

[lewlec]

Thanks for that, I am still waiting to hear from dorman smith with their final thoughts as the guys in tech were looking into it.

 

[Knobhead]

Let me know what they come up with.

We used the Telemecanique intertrip units and toggle links on vibrating feeder panels.
A fault on ether the mains or control tripped the other. The only trouble, which tripped first?

 

[lewlec]

Hi

well to say the least that dorman smith tech is pants! Still waiting for a reply after several phone calls.
any way ended up going for a 4 pole switch fuse but with 2 fuses replaced with copper links, made by a company called switchgear systems also hager offered the the same set up.

thanks for your replies
regards
gary