Pseudo three phase for a cooker

[bernardgreen]

Recent posts on cookers reminded me of an interesting solution to the local fusing of a large cooker.

The cooker was internally configured for 2 or 3 phase operation with 230 volt elements between a phase and neutral. For single phase supply all the phase inputs were paralleled to the single phase.

The wall unit contained a 3 pole isolator and two 13 amp fuses to produce two separately fused "phases" to the cooker. The supply cable was more than adequate for the possible 26 amps drawn.

I am NOT suggestiing this as a work around for DIY cooker connections as some cookers may not be safe with that supply configuration.

 

[JohnW2]

The cooker was internally configured for 2 or 3 phase operation with 230 volt elements between a phase and neutral. For single phase supply all the phase inputs were paralleled to the single phase. The wall unit contained a 3 pole isolator and two 13 amp fuses to produce two separately fused "phases" to the cooker. The supply cable was more than adequate for the possible 26 amps drawn.

Are you saying that all three elements were paralleled and fed by what is effectively two 13A fuses in parallel, down a single cable, or did one fuse supply on element and the other fuse the other two elements (separate cables)?

Kind Regards, John.

 

[Paul_C]

I'm taking it mean that a 3-way (plus earth) connection running to the cooker provided two separate live feeds fused separately from two 13A fuses, in the same way as if it were being connected to two phases & neutral of a three-phase system. It's just that there's then a single-phase feed to the isolator strapped to the two live poles which feed the fuses.

You just need to make sure that the "neutral" in this case is large enough to carry the combined load of both "phases," since the currents will be in phase and additive.

 

[bernardgreen]

The cable was 4 or 5 core E N P1 P2 (P3) effectively the cooker was 2 or 3 separate sections.

 

[ban-all-sheds]

The wall unit contained a 3 pole isolator and two 13 amp fuses to produce two separately fused "phases" to the cooker. The supply cable was more than adequate for the possible 26 amps drawn

So why not replace all the gubbins on the wall with a regular CCU supplying the cooker configured for single-phase?

 

[JohnW2]

The wall unit contained a 3 pole isolator and two 13 amp fuses to produce two separately fused "phases" to the cooker. The supply cable was more than adequate for the possible 26 amps drawn

So why not replace all the gubbins on the wall with a regular CCU supplying the cooker configured for single-phase?

I was wondering that; it's not clear what purpose the local fuses serve.

Kind Regards, John.