Thanks MIke the court will give me a date in the next few months. I will follow up on the above info.

I e mailed the manufacture with the readings, he said   "thats how they work"   so no expertise there then.

Whilst the data sheet looks simple Andy, there is no mention of the required time constants to make this work properly, in fact it is pretty much what is in the product mentioned above. PID control, think of a servo system to control a gun turret, requires that both fast response and great accuracy are available. Clearly full on or full off cannot work. The integral factor for example, integrates a tiny position error over time and then produces a very small control signal making a tiny correction to the position so that the integral error is zero. Similarly the differential part decelerates the movement as the position error gets smaller, preventing overshoot due to inertia, and the proportional part makes a reasonable guess at the movement speed needed with the starting error size. All of these depend on the applied motor (or whatever) being linear with the control signal, on-off is not.

All of these depend on the applied motor (or whatever) being linear with the control signal, on-off is not.

I think a lot of systems these days achieve an approximation of linear control with hard-on-off switching pulses and then something to smooth the results. Many inverters simply have a fixed d.c. line and switch that on or off at varying speeds/ratios to generate the output - at best a totem pole arrangement between a +ve and -ve d.c. rail - so at that point only two (or three) single voltages can be produced +dc & 0 (or +dc, 0 and -dc). It then relies on smoothing to produce an approximation to the a.c. waveform output expected - occasional narrow pulses yielding a smoothed voltage near to zero, more frequent and/or wider pulses to produce the peaks of the a.c. output. I reckon the oven is working on the same principle - just using thermal inertia rather than inductor or capacitors to do the smoothing. A 1s or 2s switching period is probably quite reasonable from a thermal point of view (if not a single phase supply point of view).

   - Andy.

I am thinking that this oven pulsing on and off meets the definition of what the DNOs consider to be a disturbing load. If it is you should have asked the DNO if you can connect the oven to their supply. I would suggest they would have said no.

As for the Wiring Regulations ( AKA Bs 7671:2018 Amd 2 2:2022 we have regulation 331.1 which Relates to Comparability of Characteristics. This regulation requires of equipment likely to impair the supply and in (iv)  is an example of rapidly fluctuating loads. Your oven fits that description.

Ask the supplier to provide you with a Declaration of Conformity to see what standards the oven complies with.

I know of a circumstance where an electrician installed an EV supply without asking the DNO. The owner of the house had a knock on the door from the DNO investigating a supply disturbance to a next door neighbors supply. It turned out the EV charger had been connected to a looped supply causing the lights to flicker. The DNO required the householder to have the EV supply disconnected. The electrician then had to pay for the excavation of the householders brick paved drive and restore it after the DNO had installed a new supply cable. 

Thanks John --  The court case has no date set yet. The current oscillation is one of a number of complaints we have with the oven. I will read up on all the excellent advice from members. before I present documents to court.

The supplier Lincat -have attended site 5 times, changed half the sensors, without avail. The Temperature and Humidity controls are all over the place.

The oven has LIncat stamped all over it. On both the hardware and software,   it came with a 2 year Lincat warentee.  Lincat first line of defense is-------  This oven is not a Lincat.!

So I ask do they  roam the country attempting to repair random faulty appliances out of altruism. ?

Tony

Yes Mike --I e mailed the design Engineer in Denmark and he replied    "Thats how they work"   I think the problem is that 99% of these ovens work on three phase. 3 x 14 amp is okay for inrush but   --   50 times a min oscillation is beyond my ken.

I will not connect that loads to my genset. The R.S.P.C, G.Set. would get me,

Anthony

Your first step should be to get their Declaration of Conformity and verify if the oven or the literature is CE or UKCA marked.  To put the oven on the UK market it has to comply with the Electrical Equipment (Safety) Regulations 2016 updated to 2022. also the EMC Regulations.