Thanks for the response guys.
Interestingly, the transformer in question is being used to reduce (Buck) the site voltage.
I'm told it's a 2000 kVA.
How does that effect the calculation??
I'll stick to generators, I understand them better!
"Power is nothing without control"
So, the original question;
Can anyone advise me if the "inrush" (or magnetising current) of a 3 phase/2000kva Buck/Boost voltage optimisation transformer is any different to a standard transformer?
I'm familiar with what I would call "normal" transformers, cast resin or oil filled, but we have...
Bill,
Thanks.
To clarify, do you mean have the transformer on the alternator (generator) side of the output/load breaker?
This would allow the voltage to build "gently",
Unfortunately this is an impossible situation as the transformer is primarily used supported from the incoming grid supply...
Dear all,
I have looked through the archived questions and cannot seem to find anything suitable (I am a man though...).
Can anyone advise me if the "inrush" (or magnetising current) of a 3 phase/2000kva Buck/Boost voltage optimisation transformer is any different to a standard transformer...
We are currently trying to find out more about the earthing systems and the protection devices installed, I will get back to you later.
"Power is nothing without control"
I agree from experience, but the consultant we are working for has asked us to substantiate our rating calculation, any ideas?
"Power is nothing without control"
Guys,
Looking through the archived Q+A's, I am unable to find a definitive answer to "How to correctly size a Neutral earth switch".
We are working under UK's G59 regulations, just to be clear.
I fully understand the reasons behind NE (or star point) switching, but I am unable to find reasoning...
For sizing a generator, don't risk using theory too much.
Have a max demand study of the actual load over a time period that would include the building(s) at maximum usage.
Use that data to size the generator.
"Power is nothing without control"
You also need to be aware that most generators will only accept a load step of 40-50% of their rating in one hit.
Depending on how the load applies itself in a mains outage, (i.e. is it staged in gradually? or all starts back in one go?) would effect the genset size.
Rule of thumb, double the...
Thanks guys.
The transducers are not broken, we are changing the control system that utilises the analogue inputs for control purposes.
The guys "on site" unfortunately don't have the correct equipment to actually "map" the correct resistance/temp/pressure curves.
Information from a colleague...
We that also, the transducer appears to be a 3 wire unit with a low pressure switch and an analogue variable resistance output and a common return lead.
Are you able to vary the turbine speed or are the vanes fixed position?
If you are unable to vary the speed, you may be better off using an inverter arrangement or an asynchronous generator.
Relating this to embedded gas/diesel generators, we have to vary the engine/alternator speed to achieve...
Guys,
Does anyone out there happen to have a resistance/temperature curve for a Cummins engine temperature transducer?
I also need a resistance/pressure curve for oil pressure.
Cummins are not being helpful and we have no accurate testing equipment on site to make the measurements ourselves...
I would agree with Scotty, but would always recommend a "local" breaker for isolation as well as protection.
Not that 150' is a huge distance, but you may want to take the generator voltage sensing point from the actual synch breaker rather than from the alternator.
