Circuit Breaker - choice and comments?

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ExeterGeek

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I was thinking that I ought to have a circuit breaker at the connection into the wall that the transformer plugs into.
(Running LGB MTS - so 5 amps)
I also believe it would be a requirement for going to a show.
Also thinking of hiring village hall for some winter indoor meets - when I presume it would be a good idea to avoid the unlikely event of blowing electrics.
Question is which one and anything that I should look out for???
e.g.
http://www.ebay.co.uk/itm/Faithfull...ptor-circuit-Breaker-/350639259364#vi-content < Link To http://www.ebay.co.uk/itm...50639259364#vi-content
Chris
 
Circuit breakers are designed to protect users of outside electrical equipment in the event of failure.

Double insulated equipment is generally quite unlikely to cause the user a problem unless it gets wet.

The normal fuse in a 13 amp plug will do fine unless you are expecting to operate trains in the rain with the controllers exposed to the elements.

It could be argued that, as an RCD would trip far quicker than a fuse, it might protect the equipment better; but then it would only trip if something had already gone wrong - it might limit the damage, but with modern electronics, probably not.

The only thing I use an RCD socket for is my water feature pump. however, my external sockets for power supply (mowers, trains etc) have MCBs in the CCU which trip far quicker than a fuse.

Any building tested in the last 5 years (and your village hall should have been) ought to have been upgraded to MCBs.

If in doubt - talk to an electrician who isn't just interested in selling you something.
 
Thanks for the comments.
We have a small electrical shop that I may well visit and discuss requirements with.
Three things set me off:
a) Helped out on stand at local model railway club show and they asked organisor if he had RCB
b) Today is showery weather here, and whllst only the trains would be aside I don't want to have to rush back to turn the power off in the event of a shower.
c) Have got an Aristocraft snowplow which in the event of me having a layout down by next winter, and there being snow, then SWMBO wants to see it working.
Chris

Rhinochugger said:
Circuit breakers are designed to protect users of outside electrical equipment in the event of failure.
Double insulated equipment is generally quite unlikely to cause the user a problem unless it gets wet.
The normal fuse in a 13 amp plug will do fine unless you are expecting to operate trains in the rain with the controllers exposed to the elements.
It could be argued that, as an RCD would trip far quicker than a fuse, it might protect the equipment better; but then it would only trip if something had already gone wrong - it might limit the damage, but with modern electronics, probably not.
The only thing I use an RCD socket for is my water feature pump. however, my external sockets for power supply (mowers, trains etc) have MCBs in the CCU which trip far quicker than a fuse.
Any building tested in the last 5 years (and your village hall should have been) ought to have been upgraded to MCBs.
If in doubt - talk to an electrician who isn't just interested in selling you something.
Click to expand...
 
Does your transformer go outside or just the low voltage output wires?
I have discussed RCDs and CCUs with various registered electricians and there seems to be some disagreement on thier use together. One view is the more breakers the better, the other view is that they can delay each other and delay the break in a faulty circuit.
My question was actually based around CCUs in garages fed from the house CCU, and wether they should be earthed back to the house mains, or to a local earth stake or both. It would appear that using both methods in a 'no'.
 
As with Stockers, if it's only the trains outside - i.e. 18v max, then there's no problem wet or dry.

If your controller is outside with 240v going into it, then use an RCD if you're likely to touch the controller when it's wet.

I don't usually play with track powered locos if the weather is threatening rain, because my controller is sat out on the decking and plugs into an outside socket. In very light spits and spots, I have hidden it under the patio table :laugh::laugh::cool: H&S advisors can look away now :bigsmile::bigsmile:
 
If you have a transformer indoors with upto 24volts going outside to a train speed controller, you will have no problems at all. As any 240 v mains outside means armoured cable, which in turn means money, don't even consider it.
 
Hi,
My two penny worth. A 13A fuse can provide 3 Kilowatts of power, much more than you require and it would be better to install a lower value fuse.
An RCD will disconnect both live and neutral and whilst any tested outlet would be properly wired, many twin wire extension leads might not. Normally it doesn't matter as we all pull the plug in the event of a problem, but I would argue that an RCD which cuts off live and neutral is much safer. Also an RCD works in a different way from a fuse as it detects an imbalance between the current flowing between live and neutral. Just 30mA difference should trip an RCD and the claim is that such a small current even at 240V is not life threatening.
Finally any circuit that can only be disconnected by 'pulling the plug' is prone to wear and tear of the cable at the plug so, if possible, use a switched socket to turn off unused equipment but again it only disconnects the live wire.
I live in France and here the MCBs in the fuse box disconnect live and neutral and because earth connections are possibly not so good this can avoid danger. The same arrangement is used in the Netherlands and the MCBs are no more expensive than the UK so I don't understand why the UK has such an unsafe arrangement.
Incidentally, MCB is Miniature Circuit Breaker and RCD is Residual Current Device. Not to be confused as they do different things.

Richard
 
Will try and explain rcd,s in outhouses, garages, etc

Under 17th edition regs the outhouse, garage, shed must have a Rcd in it's consumer unit, The cable supplying it must also come from a rcd.

Earthing this is the complex bit , If your house has a PME (or TN-C-S) supply then the supply cable has to be earthed at point of origin but not connected at the supply point, The supply point should then be treated as a TT supply and the earth connected to a Stake. This is because the outbuilding would be outside the equipotential zone.

If your house has a TN-S supply then the Earth is supplied from the Incoming Earth Point. But you can add a extra stake.

If your house has a TT system then it is permissable to add a extra Earth Stake at point of supply.

Get a Qualified electrician in and get a Part P certificate and double check the house Earthing supply
 
Interesting information from Richard there.

My understanding of UK electrical systems, is that, because we use the Ring Main system (saves on copper wiring) rather than the radial wiring used in Europe, our BS 1363 plug has to have a fuse internal to it. The Euro Shucco doesn't have a fuse of course, so you need a MCB for each outlet.

Also the BS 1363 plug can only be plugged in one way, whereas the Euro Shucco can be still be plugged in if you rotate it by 180 degrees. Thus you can swap the neutral and live feeds and hence the reason why you have a MCB on both neutral and live connections of any outlet.

UK Earthing is also very sound (if installed correctly of course!) and should the metal casing of an appliance become live due to a fault, the short to earth will very quickly blow the fuse in the plug, thus protecting anyone using it and also the ring main itself.

I beg to differ that the UK has an unsafe arrangement; it's just a different way of doing things due to the UK using Ring Main wiring....
 
Any new Installation in Uk should have Switched Socket Outlets to BS 1363 with the reference to 17th Edition that they be double pole switched
 
All,
Couple of clarifications are in order.
Shucco plugs can be polarity dependent but it actually depends on the socket, so here in France the earth pin fixes it, whereas in the Netherlands there is no such pin and no polarity. Hence no one assumes polarity and defaults to worst case. However, twin (no earth) plugs for use outdoors have no polarity. In NL and FR each room is fused with sockets spurred from a central (to the room) distribution box and feed.

Beware of electrical imports which use a two pin to UK three pin adapter as this is just as likely to confuse polarity at the appliance.

In all of the above thread there are a lot of instances of the word 'should' and having worked in the petrochemical industry any possible single point of failure has a hazard analysis carried out and often a double protection measure is used such that no single error can cause significant issue. Indeed often the biggest risk is where a safety device is routinely disabled.

As noted by Sparky, earthing can be key to safety which is why an RCD is necessary in sheds and for extension leads used in the garden.
The UK ring main solution has been around for fifty? years and much of it was installed by DIY electricians. Whilst an electrical test should reveal faulty wiring it will not reveal badly installed wiring. I just fixed some garden lighting around our pool and a junction box had been installed upside down and when it rained it got water inside so intermittently tripped the RCD. I've tested this many times trying to find the problem but never in the rain. It has rained so much this year that the box was full of water and eventually the fault is fixed. Without an RCD things would not have been safe. On a bad day it tripped three RCDs including the main incoming three phase RCD. I also once had a friend (no longer) whose whole house had an earth which floated at 120V AC and where someone had used the earth core in places as a useful conductor!!

So I re-iterate, a 13A fuse is for appliances that draw 3KW and much lower value fuses are often much more appropriate (table lamps are a good example). An RCD offers additional different protection and many new UK installations incorporate a split consumer unit with either one (cheaper) or two RCDs to protect the whole house. So I would definitely incorporate one in any electrical apparatus I used away from home.

Regards

Richard
 
This has been an interesting discussion for me. As I am in the States our wiring is different than what you have in the UK. I assume your RCI is the same as what we refer to as a GFCI or ground fault circuit interrupter. Our house is older so GFCIs were not installed in our kitchen or bathrooms or outside. So, I installed them myself. They are not expensive here in the US and can be installed in individual outlets. At some time in the future when I am upgrading the electrical service to the house, I will install a 'whole house GFCI'.

I have a portable GFCI that I can use outside when I am using electrical tools or equipment near wet areas. I also use it when my wife is going to use a hedge trimmer or the like. Years ago I used it when she was trimming some heavy growth of ivy. It worked very well when she cut into the cord and the electricity was shut off immediately. GFCIs save lives as well as equipment.

Portable GFCI's are cheap and can be purchased for our equivalent of about £10. If you are using electricity outside with extension cords, use one at the source or a portable. If you are running trains at a show venue and the electrical circuits seem questionable, use a portable GFCI/RCD. They should be available at your local DIY center or through Amazon. Protect your equipment and yourself.
 
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