Need MEM 451QEB MCB

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I need to change a 32A MCB for a 45A. I require an MEM 451QEB. Can anyone tell me if there is a newer model that will fit in it’s place as I can only find second hand due to this model being obsolete?
Thanks in advance
 
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I would say your unlikely to find one in new condition, and I wonder why you would want one? To change to a larger one the circuit needs to be suitable, so heavy enough cable, not only to take current but also ensure the loop impedance is low enough. Type B MCB is x5 not got an old enough copy of BS 7671 to look up type 1, so 230/(32*5) = 1.4375 Ω x 95% =
1.365625 Ω with a 45 amp = 0.971111 Ω cheap plug in testers even with loop only go to 1.9 Ω so you need an expensive loop impedance meter to test.

Also question of how you will get RCD protection?

So to my mind alarm bells are ringing, why would you want to change to 45 amp?

I don't think the distribution boxes that took those fuses were consumer units, so not permitted if under the control of an ordinary person, so looking at a commercial set up not domestic, so then HSE comes in, and also minor works certificate etc. I would not want my name on the certificate I would simply tell boss needs a new consumer unit before it can be changed.
 
Can anyone tell me if there is a newer model that will fit in it’s place
Those MCBs and the consumer unit they fit into have been obsolete for over 25 years.
There is no modern alternative.

If a new 45A circuit is required, the only option is a new consumer unit.
 
Just to reaaaaaaly annoy, earlier this year I sent a box full of mcb's for recycling, including 4 of those. One was installed to power a 4 channel dimmer pack which we'd been told was rated at 10A per channel, however it had 4 3A fuses and a 1.5mm² supply flex so MCB changed to a lower rating. The other 3 intended for the same set-up were still in their unopened boxes.
 
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There is currently a 45A MCB the consumer unit for the shower. The 32A is what supplies the cooker circuit. We are having a new cooker and hob fitted which requires the 45A MCB. The wiring will be getting upgraded. I only wanted to know if there was a replacement MCB available that would fit in the existing consumer unit.
 
There is currently a 45A MCB the consumer unit for the shower. The 32A is what supplies the cooker circuit. We are having a new cooker and hob fitted which requires the 45A MCB. The wiring will be getting upgraded. I only wanted to know if there was a replacement MCB available that would fit in the existing consumer unit.
No not new stock.
 
I haven’t. The new hob is a 6.6kw Neff ceramic hob. I don’t have the details of the oven at the moment but going by the size of the hob, the 32 MCB and 6mm cable that supply the existing cooker will not be suitable.
 
I haven’t. The new hob is a 6.6kw Neff ceramic hob. I don’t have the details of the oven at the moment but going by the size of the hob, the 32 MCB and 6mm cable that supply the existing cooker will not be suitable.
Yes it will. Hobs and ovens cycle on and off on their thermostats. The only time it will draw 6.6kW will be if you turn everything on at once until the first stat opens, very unlikely you will do that. 32 amp is a standard cooker circuit and will be perfectly OK. 6mm cable is rated up to 47 amps so will be OK even with a 45 a MCB.
 
I haven’t. The new hob is a 6.6kw Neff ceramic hob. I don’t have the details of the oven at the moment but going by the size of the hob, the 32 MCB and 6mm cable that supply the existing cooker will not be suitable.
Ah! new hob and new oven, 2 separate units? maybe cheaper to add a second (Smaller) supply rather than replace if you actually need to.

6mm² cable is rated well over 40A so may be big enough for a 45A MCB depending on installation methods.

The oven is likely to be around 3KW or 5KW for a double. so about 12KW total. Winston1 quite correctly mentions diversity and it looks like you may not need to upgrade at all.

Not sure if my knowledge is current but my understanding for a cooker:
first 10A + 50% of the rest.
12KW is 53A 43A/2 = 21.5A + 10A = 31.5A which is spot on. However I stress I may not be using current rules and I'm estimating oven power.

EDIT since starting to write this reply there are other replies mentioning the same thing.
 
There is one question I will ask:

Is this in a domestic kitchen and is it likely to be in above average use, like in a catering situation?
 
In that case you seem to have 3 votes for leaving as it is as long as it's not silly amounts above 12KW total.
 
Not sure if my knowledge is current but my understanding for a cooker:
first 10A + 50% of the rest.
No, first 10A + 30% (+5A if socket on cooker switch).
It has been that 'for ever' I think.

So; 12kW @ 240 = 50A, which @ 230V = 47.9A; 10 + (37.9x0.3) = 21.37A (26.37A with socket).

The 32A circuit is good for 15kW with socket and 19kW without socket.
 

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