There's been a question raised about DGA sampling methods in our organization. The procedure calls for filling both a syringe and a 0.5L glass bottle. The question is, how much airspace should be left in the top of the 0.5L bottle to allow for expansion? The opinions range from "a little bit" to...
I have tried to find this information online, but I can't seem to find a difinitive answer.
In our country we are starting to install quite a few large battery systems to try to cut back on peaker plants, along with many others I assume. I am curious though, at the 100MW+ size installations...
If I wanted to run 3 + (1 backup) 1MW 415V generators into a single output, I would expect to have 4 2000A c/b's bussed using copper bar to a single 6300A circuit breaker that would provide the feed out (with OCR's set to correct levels obviously). Even if it was aligned with the 6300A breaker...
Have done quite a few different searches here, and can't pin down which standard I need to get. I cannot find, in Australia, a standard that guides de-rating factors for higher-than-nameplate ambient temps. That is, if I have a 60 - 65 transformer (oil - winding), that is designed for 40 degree...
Just a quick question, had a search through and couldn't find an answer:
By IEC60076, when doing a separate source voltage withstand test on a transformer, all terminals of the winding under test must be connected together, and all other windings / metal parts, etc have to be connected to...
Quick question:
If you use a generator (say 750kVA) as a power supply, stepping up through a 500kVA transformer with around 5% impedance, then try to DOL start a 180kW SC motor hooked up to a fan. Will the generator see a significantly lower startup current than if a 1500kVA 5% impedance...
I'm looking at making a submerged PC, which is part for fun and part so that it is completely silent. What that basically means is the motherboard, plugged in expansion cards, and the power supply are all submerged in a dielectric liquid - generally oil.
However, a lot of the capacitors in the...
My boss asked me today to figure out what short circuit capacity a switchboard would need to be designed for given:
2 x gensets with 22kA fault rating each (1 MW 50hz 415V sets, got the kA from manufacturer)
Synced onto a common bus in the switchboard
Each genset will be connected through a...
Does anyone have any experience with 3 phase transformer turns ratio test sets? Specifically, which one is likely to be reliable and FAST?
We have the little ttr100 single phase from Megger, and its so slow that in the time it takes to test 1 tap on 1 phase, our AEMC 8500 can do at least 2...
We have an oldish (mid 90's) ABB Power factor correction system that was found in a warehouse and dropped off to us as a freebie. It has 9 50kVAR capacitors + reactors rated at 415V, and an ABB relay to allow for automatic operation or each bank can be switched in manually. The control circuit...