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Author 3 Phase MCB
amp is

2008-03-30, 9:25 am

I have a 3 section 3 phase MCB rated at 25A.
Is this 25A total or 25A on each phase?

TIA.


Palindrome

2008-03-30, 9:25 am

amp is wrote:
> I have a 3 section 3 phase MCB rated at 25A.
> Is this 25A total or 25A on each phase?
>

Consult the manufacturer's specification for the product.

Never take any "advice" with safety implications off a usenet group -
especially this one.

Oops, I have just given some advice with safety implications....

--
Sue
amp is

2008-03-30, 1:25 pm

UK by the way



"amp is" <thisisnotmy@address.com> wrote in message
news:fsnnfp$71r$1@aioe.org...
>I have a 3 section 3 phase MCB rated at 25A.
> Is this 25A total or 25A on each phase?
>
> TIA.
>



James Sweet

2008-03-30, 1:25 pm



"amp is" <thisisnotmy@address.com> wrote in message
news:fsogo7$4ad$1@aioe.org...
> UK by the way
>
>
>
> "amp is" <thisisnotmy@address.com> wrote in message
> news:fsnnfp$71r$1@aioe.org...
>
>


It's almost certainly 25A each phase. I've never seen it rated any other
way.


amp is

2008-03-30, 5:25 pm

Thanks James.



"amp is" <thisisnotmy@address.com> wrote in message
news:fsnnfp$71r$1@aioe.org...
>I have a 3 section 3 phase MCB rated at 25A.
> Is this 25A total or 25A on each phase?
>
> TIA.
>



phil-news-nospam@ipal.net

2008-03-30, 5:25 pm

On Sun, 30 Mar 2008 11:44:57 +0200 amp is <thisisnotmy@address.com> wrote:

| I have a 3 section 3 phase MCB rated at 25A.
| Is this 25A total or 25A on each phase?

Some models have 1, 2, and 3 pole variations. The 3 pole ones can still
be used on 3 separate single phase circuits. So that would seem to imply
that it's the specified amperage for each phase, sensed individually (so
one of them going over-current would trip them all together ... not the
sum of currents exceeding some rating or sum of ratings).

--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / spamtrap-2008-03-30-1621@ipal.net |
|------------------------------------/-------------------------------------|
Palindrome

2008-03-30, 5:25 pm

phil-news-nospam@ipal.net wrote:
> On Sun, 30 Mar 2008 11:44:57 +0200 amp is <thisisnotmy@address.com> wrote:
>
> | I have a 3 section 3 phase MCB rated at 25A.
> | Is this 25A total or 25A on each phase?
>
> Some models have 1, 2, and 3 pole variations. The 3 pole ones can still
> be used on 3 separate single phase circuits. So that would seem to imply
> that it's the specified amperage for each phase, sensed individually (so
> one of them going over-current would trip them all together ... not the
> sum of currents exceeding some rating or sum of ratings).
>

As James wrote, it is almost certainly a rating per contact pair. I've
never encountered one that hasn't been.

But if I was in any doubt, I'd turn to the manufacturer's data sheet.

Three phase at ~25A could cause a great deal of damage.

--
Sue

Ryan Evans

2008-03-30, 5:25 pm

Each. Draw 25+ amps on any phase = trip

RE


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