Rotary phase converter

At present In the UK domestic installations electricity charges are based on recorded kWh consumed, PF is not a factor in costs charged, this may change in years to come when every consumer is on so called smart meters.
So for a more accurate estimation of cost any Test recording meter should ignore PF.

Emgee

Edited By Emgee on 26/08/2020 17:56:17

Dave,

I absolutely agree with you and the numbers will be small. But I would be remiss as an Electrical Engineer not to point out the effect of power factor on this type of measurement. Very significant if the rotary converter runs at light load for long periods of time. The measurement could be significantly out depending on the load profile leading you to think it is costing much more to run than you think.

I might actually be concerned to hear that the converter costs me more than 0.6kWh to run on no load which should not be the case. All about getting the correct numbers into peoples minds so they feel comfortable using the kit at all.

Also to point out that some low cost power measurement meters might also have this error.

What could be said in absence of a good power meter measurement is that the cost to run at all states of load should be "significantly less" than that computed by the apparent power method, especially at light loads.

Also good to have a lively discussion which is my first as a newbe to ME forums !

Adrian

Agreed Emgee and one reason why I will not sign up for a smart meter. One never knows how the measurements will change over time and what trickery is going on in the background.

Good old real power kWh as per current situation in the UK is good enough for me !

Adrian

Hi guys .w ell that generated a bit of discussion.I'm only a hobbist and built the rotary inverter myself.I run a bandsaw and a mill with two speed motors with the inverter.I was told at the time that a VFD would have problems running and two speed motor and would be expensive to buy.

Andy

Is the 2 speed motor you are running 2 sets of windings, high and low, or do you have to short out 1 set and apply power to the other set for high speed. ?

Emgee

Emgee all I do is flick the switch on the mill or bandsaw and it changes speed.

I take it you didn't connect the control gear then ? Do you run a pilot motor to assist starting ?

Emgee

Is the Seimec motor pic in your album being supplied with the converter ?

Edited By Emgee on 27/08/2020 15:36:14

Yes theSeimec is run by the inverter.No pilot motor.Which control gear?Everything on lathe,mill and bandsaw work just like if they plugged into mails three phase.

mains