2 Ovens on Cooker Circuit

[JohnW2]

If by "sideways" you mean with the MCB not facing you - i.e. with the DIN rail it's on at right angles to the plane of the wall, (the MCB could still be vertical) then I think a 2-module enclosure would be shallower than a KMF 800.

Yes, that's what I meant, and yes, if one did that, I'm sure that a 1-module (or probably even 2-module) enclosure for the MCBs would be shallower than a KMF800. However, I'm not aware of any such enclosures being available off-the-shelf, and if one was going to manufacture/improvise one, one would have to give some consideration to the amount of air circulation/ventilation required around the MCB. If one used a standard off-the-shelf 2-module enclosure and mounted it sideways (with MCBs facing to left or right), I think it would probably be appreciably deeper than a KMF800.

However, conceptually, 'sideways MCBs' would seem to be a viable idea.

Kind Regards, John

 

[JohnW2]

Many of these ovens which state 16A fuse are needed do not require 16A at all. The actual rating is often far less, and the easiest method is to get a list of replacement elements for the oven and see what rating they are. Typically 2.5kW .... For those which have multiple heating elements, it is almost always the case that only one element can be selected at a time (e.g grill or oven), or the combined total of the elements which can be used simultaneously is still far less than 16A.

I'm sure that's all true, but it's little consolation for those (such as scheme-registered electricians) who are constrained to strict compliance with the word of BS7671 - hence also MIs if they call for a 15A/16A MCB (even if that is not necessary, engineering-wise). It's perhaps one of those situations in which a non-electrician applying engineering principles and common sense might be in an 'easier' position

Kind Regards, John

 

[ban-all-sheds]

However, I'm not aware of any such enclosures being available off-the-shelf, and if one was going to manufacture/improvise one, one would have to give some consideration to the amount of air circulation/ventilation required around the MCB. If one used a standard off-the-shelf 2-module enclosure and mounted it sideways (with MCBs facing to left or right), I think it would probably be appreciably deeper than a KMF800

http://www.tlc-direct.co.uk/Products/BHCT2.html

 

[JohnW2]

As I said, "I suspect that they may detract to some extent from the small overall size of the KMF800, which is its main attraction". A pair of those things would considerably increase the footprint.

Kind Regards, John

 

[JohnW2]

... If one used a standard off-the-shelf 2-module enclosure and mounted it sideways (with MCBs facing to left or right), I think it would probably be appreciably deeper than a KMF800

http://www.tlc-direct.co.uk/Products/BHCT2.html

I have to concede - it's not 'appreciably deeper'. In fact, if one includes the switch of the KMF800, the enclosure is actually less deep:

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• JohnW2
• 11 Apr 2013
• 1

A 1-module enclosure, if it existed (never seen one) would obviously be far less deep.

Kind Regards, John

 

[ban-all-sheds]

Slim ABS box fixed to wall, panel mount fuse holder(s) (20 or 32mm fuse size) mounted on one of the sides.

 

[JohnW2]

Slim ABS box fixed to wall, panel mount fuse holder(s) (20 or 32mm fuse size) mounted on one of the sides.

Yep, that's also a viable option. One could also contemplate mounting a 'sideways' MCB in such a box - but, as I said, I'm not sure about the thermal considerations.

Kind Regards, John

 

[mfarrow]

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• JohnW2
• 11 Apr 2013
• 1

The one BAS linked to is 49mm wide (or deep, depending on which way you land it). The 800KMF is 66mm deep excluding switch lever.

 

[JohnW2]

The one BAS linked to is 49mm wide (or deep, depending on which way you land it). The 800KMF is 66mm deep excluding switch lever.

FWIW, the KMF800 I photographed (a real MEM one) is about 66mm deep including the switch lever, 54mm excluding the lever - and the enclosure I had to had was slightly wider than TLC one at about 53mm.

Whatever, I've already conceded the point - that a 2-module enclosure on its side can be 'less deep' than a KMF800, certainly when one takes the lever into account.

Kind Regards, John

 

[ban-all-sheds]

Yep, that's also a viable option. One could also contemplate mounting a 'sideways' MCB in such a box - but, as I said, I'm not sure about the thermal considerations.

Panel mount fuse holders would be much easier - one round hoe and you're away, no rail to find room for. And you'd probably find that a 25mm deep box would be ample.

Of course, what would be ideal, as I've observed before, would be cosmetically acceptable panel-mount MCBs as part of a comprehensive grid system. If people are happy to have grid switches, or FCUs, or isolators on the walls above or near appliances, why not something with a circuit breaker in?

I'm sure they could make them to fit a grid.

 

[JohnW2]

Of course, what would be ideal, as I've observed before, would be cosmetically acceptable panel-mount MCBs as part of a comprehensive grid system. If people are happy to have grid switches, or FCUs, or isolators on the walls above or near appliances, why not something with a circuit breaker in? I'm sure they could make them to fit a grid.

I would be surprised if that idea has not been investigated, so maybe it's not as easy as you think to minaturise a, say, 16A or 20A MCB - at least, in a cost-effective manner.

Don't forget that there are probably some 'absolutes' which would probably not be ameniable to minaturisation - like required contact size and contact separation, size of required 'arc chamber' etc.

Kind Regards, John

 

[ban-all-sheds]

With a slight redesign of the terminals the ones in the photos would be fine in a 47mm deep box.

 

[mfarrow]

FWIW, the KMF800 I photographed (a real MEM one) is about 66mm deep including the switch lever

Eaton stand to be corrected then!

http://www.neweysonline.co.uk/neweys/pdf/MEM_SP_&_N_Switchfuses_800KMF_Technical.pdf

 

[JohnW2]

FWIW, the KMF800 I photographed (a real MEM one) is about 66mm deep including the switch lever

Eaton stand to be corrected then!
http://www.neweysonline.co.uk/neweys/pdf/MEM_SP_&_N_Switchfuses_800KMF_Technical.pdf[/QUOTE]
Yes, it looks as if they do:

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• JohnW2
• 12 Apr 2013
• 1

There's a bit of an optical illusion due to parallex in the photo - the depth including the switch lever is something approaching 66mm, even though it does not look like it. Of course, it's possible that the Eaton leflet was correct when written, but that the specimen I have is earlier or later in date, at a time when the dimensions were slightly different;my one has probably been in my cupboard for a couple of years.

Kind Regards, John

 

[OwainDIYer]

Of course, what would be ideal, as I've observed before, would be cosmetically acceptable panel-mount MCBs as part of a comprehensive grid system. ...

I would be surprised if that idea has not been investigated, so maybe it's not as easy as you think to minaturise a, say, 16A or 20A MCB - at least, in a cost-effective manner.

Don't forget that there are probably some 'absolutes' which would probably not be ameniable to minaturisation - like required contact size and contact separation, size of required 'arc chamber' etc.

13A RCDs (with a fuse) have got reduced to fit a one gang faceplate. With a deep mounting box, and possibly a somewhat protruding faceplate, I think it should be do-able for either 1 x 20A or 2 x 20A.

Of course 2 x 20A doesn't work as well as 1 x 30A for diversity, but if it enables Continental ovens to be wired to British circuits perhaps it's something that needs to be considered.