Which fuse size needed for my oven circuit?

If its a Wylex Standard (it usually is) then, no, it's not very simple, because the base is designed to prevent a different rating fitting.
IIRC the pins get wider as you move to higher ratingss. So you can plug a lower rated fuse/breaker into a higher rated base but not vice-versa.

However there are two different styles of base. The "rewirable" base and the "cartridge fuse" base which afaict are not compatible. I've seen pictures of MCBs with both styles of base.
 
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IIRC the pins get wider as you move to higher ratingss. So you can plug a lower rated fuse/breaker into a higher rated base but not vice-versa.

However there are two different styles of base. The "rewirable" base and the "cartridge fuse" base which afaict are not compatible. I've seen pictures of MCBs with both styles of base.
I believe, but may be completely wrong, the only sizes which fit in wrong bases are 15A & 20A, blue and yellow.

EDIT: Ah second thoughts, fuse and MCB bases are different and you may have a good point there.
 
I thought the re-wire-able, cartridge, and MCB were all different with the Wylex fuse box? it is only one screw to change the base, but do make sure main isolator is off as live parts exposed.

Personally I would not change the fuse/MCB as once reduced in size, in the future you don't know if the size can be increased again.

Although my old house the Wylex fuse box was RCD protected, Wilex-board-with-RCD.jpg this is unusual, also the old Wylex can only have over 32 amp in one slot which has reinforced contacts Wylex heavy duty.jpg and the main switch is limited to 60 amp Wylex 60 amp.jpg so at some point in the future your likely to want to change it for a modern consumer unit. It took me 6 months after I moved into this house, but the problem is without RCD protection although the regulations are not retrospective so existing things can continue to be used, at some point you will want some thing which means RCD's need to be fitted, new shower, new boiler, new socket, etc.

So it is just throwing money away buying some thing which will likely be scrapped in the not so distance future.
 
I thought the re-wire-able, cartridge, and MCB were all different with the Wylex fuse box?

Yes, in the past I have changed fuseholders for MCBs and they were different. I have an idea some of them were almost the same but not quite. I think it was positioning, not size.
 
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Just to sum this thread up, I understand it's not necessary to change to a lower-rated MCB for my oven, and the MCB for the most part not interchangeable.

The reason for no need to change MCB is MCB is mainly there to protect the cable, as long as the cable is suitably rated, that should be ok. If there is a short/fault then the current surge would be much more than 32A anyway, is my understanding correct?

Another point, I thought changing the MCB is a simple job of changing the base (then then MCB), which is hold in place with just a screw. Or there is more to it?
 
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Just to sum this thread up, I understand it's not necessary to change to a lower-rated MCB for my oven, and the MCB for the most part not interchangeable.

The reason for no need to change MCB is MCB is mainly there to protect the cable, as long as the cable is suitably rated, that should be ok. If there is a short/fault then the current surge would be much more than 32A anyway, is my understanding correct?
Correct.
Another point, I thought changing the MCB is a simple job of changing the base (then then MCB), which is hold in place with just a screw. Or there is more to it?
That's it: Check cable size, turn main swith off, remove MCB, one screw to remove base, one screw to fit new base, insert new MCB, turn power on.
 

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