Amp for table saw

[brianhabby]

Hi there,

I'm sure this question must have arisen before but I can't find any appropriate posts.

Last weekend I replaced the consumer unit in my workshop (see this) and now I can't use my table saw.

The ring main is on a 16 amp MCB and the manual says I need a 10amp fuse but the MCB trips when I try to switch the saw on.

My saw is a 10" SIP (3HP)

Any ideas?

regards

Brian

 

[OLD]

I need a 16amp feed (unfused blue plug/socket) to my sip saw wired on a separate circuit with its own mcb.
It did work on a 13amp ring but kept blowing the fuse in the plug.

 

[brianhabby]

Hi Old,

When you say a 16 amp feed, do you mean it is on a 16 amp MCB because that is what mine is on and there was nothing else running when I tried to switch the saw on?

regards

Brian

 

[Jake]

Have you checked your wiring again?

Does anything else work on that socket?

 

[paulm]

Might be the startup current that triggers the trip.

Think you can get a different type of mcb ( C instead of B, or it might be the other way round !) that is more tolerant of startup surges but still gives the 16amp rating ongoing.

Cheers, Paul

 

[brianhabby]

Have you checked your wiring again?

Does anything else work on that socket?

Absolutely nothing else on that circuit when I tried starting the saw. Other tools work okay when I have tried them so the circuit must be okay.

regards

Brian

 

[matt]

Go back to the old fuses... They look far more capable

 

[andycktm]

Like chisel says you need 16amp type "C" breaker for induction loads.
Although the saw may only use say 12amps when its running it may try to take a lot more to start up

 

[brianhabby]

Like chisel says you need 16amp type "C" breaker for induction loads.
Although the saw may only use say 12amps when its running it may try to take a lot more to start up

I wondered if that might be the answer although I was thinking along the lines of a higher rated MCB. I'll see what is available at the electrical suppliers. Thanks for all your input,

regards

Brian

PS

Go back to the old fuses... They look far more capable

Yeah right :lol:

 

[matt]

Looks as though you may have stumbled across the answer to one of my problems (at least a short-term solution I can use until I get round to beefing up the main supply to the garage).

Yeay!

 

[andycktm]

I was thinking along the lines of a higher rated MCB.

That is a common mistake 32amp breaker,if the motor goes mad and tries to draw 20 amps(continuous) the 16amp rcd trips,
where as the 32amp will let the motor hang itself

 

[paulm]

Don't just go from a 16amp mcb to anything higher, it needs to be matched to the wiring.

If you just increase the ampage of the mcb then in the event of a fault the wiring might melt or catch fire before the mcb trips !

Just change from 16amp type B to 16 amp type C as Andy confirmed.

Cheers, Paul

 

[matt]

At the risk of hijacking your thread (perhaps asking a question you already know the answer to). However, a quick question about changing the MCB...

It is simply a case of popping off the CU cover, being very careful not to touch the rails, and taking out the old MCB and putting in the new one, before replacing the cover)?

 

[RogerS]

Brian, what does your electrician suggest? Didn't he check it out when he signed off your certificate :wink:

 

[andycktm]

Isolate first!!!!!
I'd only do it if your 99% sure you know what your doing

Here's a type c for a wylex

http://www.screwfix.com/prods/35400/Ele ... -Curve-MCB

 

[matt]

Isolate first!!!!!
I'd only do it if your 99% sure you know what your doing

Here's a type c for a wylex

http://www.screwfix.com/prods/35400/Ele ... -Curve-MCB

Hmmm... It's the isolate bit that made me ask the question. How?

 

[brianhabby]

Brian, what does your electrician suggest? Didn't he check it out when he signed off your certificate :wink:

mmmm - I did it myself, but then you probably guessed that

I think I'll go looking for a type C at the suppliers.

regards

Brian

 

[Jake]

You say this is on a ring?

 

[brianhabby]

You say this is on a ring?

Yes

 

[Jake]

I asked because a 16A ring is unusual.

I'm not sure a C-class breaker on a ring used for other stuff is a good idea.

Any spare ways in the new CU you installed?