# Type C RCB



## Junah (11 Oct 2021)

I’m nearly ready to buy a bandsaw, some recommend using a 16 amp type C circuit breaker, I have a 16 amp outlet running from the circuit board but it is a type B, will the bandsaw still work safely?
Don’t seem to be able to find a type C for a Legrand 06160 board anywhere. 
I run it through one of these from the circuit board with a type B in at the moment.


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## clogs (11 Oct 2021)

I'm guessing it'll be OK....
on a 13 amp supply pulling nearly max or on inrush startup supply is the reason for a C type RCD....C type RCD just take a little longer to trip out....
often used on big single phase compressors....

diff kettle o fish with 16amp supply......
even better is 3 phase....


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## guineafowl21 (11 Oct 2021)

Your current set up will be perfectly safe, but you might get nuisance tripping on start-up of the bandsaw as mentioned by clogs. The bandsaw’s manual should specify the type of supply, so consult that when it arrives.

Ideally the circuit should be loop tested before changing the breaker from B to C.


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## Junah (11 Oct 2021)

Thanks for the answers, Think I'll just have to go for it and see if I need to make changes after I've tried it.


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## Myfordman (11 Oct 2021)

The screwfix electricians forum is a good source of knowledge on whose breakers fit whose cu s
Sparks have to deal with compatibility issues all the time. 
eBay is a good source of older breakers once you know what fits what.


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## Spectric (11 Oct 2021)

All the type means is the amount of current needed to cause it to disconnect, type B needs 3 to 5 times rated current and a C needs 5 to 10 times rated current.

This is why you cannot just swap a C for a B because you need to know that the circuit impedance is low enough to allow the higher current to flow otherwise it will not trip. The 16 amp B needs 80 amps worst case, the type C could be 160 amps.

I would try running it on the type B before any changes, the only thing I have on a 16 amp is my Record P/T and that is a type B, the BS400 and table saw are both happy on a 13 amp socket.


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## Sideways (11 Oct 2021)

Changing the type of protection on a circuit isn't maintenance. It's modification of a design that was (officially at least) made by someone qualified to do so.
The wiring of this circuit would have been selected on the basis of a 16amp type B miniature circuit breaker. If you change the breaker, you invalidate the original design.
That will make it building control notifiable work that is easiest done by a sparky who can check it and certify it as safe.
Be aware that you are giving your insurance company a get out of jail free card if you DIY this and then cause an overload and burn your house down.


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## Junah (11 Oct 2021)

Thanks for all your advice, the 16 amp supply was fitted by a qualified electrician and certified by the local council, any further alterations would be done the same way.


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## Ttrees (11 Oct 2021)

VFD's are around the same price as that socket if you are concerned, and you would save two thirds of your budget if you went second hand three phase.
Just make sure you can see that it's got 240v on the motor nameplate
(denoting it is a dual voltage three phase motor.)

That way you wouldn't have to worry about a machine tripping the breaker on start up. 
The split second surge from starting is what the issue is with single phase, not whilst running.

My 24" machine running on idle uses about the same juice as my old laptop, much less than a kettle for instance, and runs from a household plug.
I can adjust the soft start with the touch of a button to suit, say add another second to make things easier on the supply.
Not important now, but if I as in another workshop with better supply, then that might be of importance if wanting to start it whilst another machine is running.

Just make sure you can see 240v _(triangle symbol) _meaning "Delta" low voltage configuration, 
as some motors are fixed in (_Y symbol) _"star" high voltage 380/400v and are not near as easy to run from a VFD/inverter.

Simple to hook up, making/adapting a metal box for it is about the most work involved,
after you've got a grasp on Myfordman's treatise on the subject.
Just don't youtube it and have at it, plenty of articles on the subject.

Just saying incase you have a very nice machine near you for much less money.
All the best

Tom


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## NetBlindPaul (12 Oct 2021)

If “electricians” on the Screwfix forum are making recommendations on mixing and matching circuit protection devices and boards then it’s not a good place to get advice.
For over 30 years the practice of “mixing and matching” boards and protective devices has been against the product safety standards unless all manufacturers agree that the parts are compatible.

You should be able to source a Legrand C16.

Used devices may be life expired and you can’t tell until it doesn’t work as required.

To change the device you need to be sure that you can achieve disconnection for safety & document this, otherwise you are giving your insurance company a reason not to pay out for a claim. Possibly any claim depending upon the small print.


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## MikeJhn (12 Oct 2021)

Your insurance company can not refuse to pay out, you and they have a contract that they must honour, they can however attribute contributory negligence and lower the payout of any claim.


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## NetBlindPaul (13 Oct 2021)

MikeJhn said:


> Your insurance company can not refuse to pay out, you and they have a contract that they must honour, they can however attribute contributory negligence and lower the payout of any claim.


If you are in breach of said contract I don’t think that they have to pay out.
That’s certainly the case for business policies.


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## Spectric (14 Oct 2021)

I think it applies to all insurance policies, we all know they like to find a "get out" excuse so don't give them one. Some years back whilst living down south there was a house fire, destroyed kitchen and a bedroom. I knew the neighbour well, the insurance company concluded it was as the result of the electrical supply to outside lighting and water features inc a large fish pond. The work was "sub standard and dangerous" so they concluded not an installation by a competant person and no record of the work being done, they just refused the claim and deemed the policy void.

It makes sense when you think of it, it would be like getting life insurance a couple of weeks before you die of a known long term condition or poisoning the wife to get insurance, delivering a dodgy job is no different.


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## Phil Pascoe (14 Oct 2021)

My sparkie told me he knew of a house locally where the insurance company had refused to pay out for damage done by a leaking water pipe because their electrical test documents were out of date.


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## Junah (15 Oct 2021)

This thread seems to have turned into insurance advise, I have said the current 16 amp supply is certificated by the qualified electrician and the local council, I'm off today to buy a bandsaw, looking at them, I'll probably get an Axminster trade with 13 amp plug.


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## MikeJhn (16 Oct 2021)

NetBlindPaul said:


> If you are in breach of said contract I don’t think that they have to pay out.
> That’s certainly the case for business policies.


The only time an insurance company can refuse to pay out is if the initial applications for insurance was falsified or a false claim is made, both breach's of contract, any other reason needs investigating to establish what really happened, in a previous life I worked very closely with the Insurance Ombudsman, it's surprising what some people will make up and try to claim for.


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## Spectric (16 Oct 2021)

MikeJhn said:


> it's surprising what some people will make up and try to claim for.


To many people treat insurance companies as stupid, they are not and if the claim arouses suspicion it will get investigated and physology also plays a part, they have a good idea when you may be telling porkies.


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## NetBlindPaul (18 Oct 2021)

MikeJhn said:


> The only time an insurance company can refuse to pay out is if the initial applications for insurance was falsified or a false claim is made, both breach's of contract, any other reason needs investigating to establish what really happened, in a previous life I worked very closely with the Insurance Ombudsman, it's surprising what some people will make up and try to claim for.


Breach of the terms of the policy is also grounds to refuse a claim is it not.


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## MikeJhn (20 Oct 2021)

In broad terms no, but according to how that is interpreted, blatant abuse of the terms and conditions then maybe, but the human factor is taken into account, if you rear ended someone in your car, but your car is found to have a tyre below the legal tread depth (road worthy condition clause) you could be found to have contributed to the accident, but the insurance company will still have to pay for the repairs to the other car and may reduce the payout on the repairs to your car due to contributory negligence, following any incident of that type the insurance company could refuse to continue cover, but they still had to pay out for the risk covered.


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