Conversion equations

[willip]

Hi guys, I'm really kind of new to the "big" electric stuff (I'm an Instrumentation Engineer by trade) and I've inherited the electrical department all the way back to the 11,000v incomming sub-station.
To my shame, I have forgoten some of the basic unit conversion equations, eg MVA to kW, the relationship between MVA and output current etc............
So can anyone help me out with a list of general conversions or does anyone know of any web-sites that have this type of information on them?

Many thanks guys....
Phil.

 

[JCCG]

Remembers the power triangle :

Apparent power: S [kVA]
real power: P [kW] (x axis)
reactive power: Q [kVAR] (y axis)

kW = kVA x power factor

Power factor = cos (angle betweent P ans S)

 

[wbd]

Don't forgot the square root of 3 for converting 3 phase line to line voltages to line to ground.

 

[Zogzog]

You might want to attend a substation maintenance training course to refresh your memory and get caught up to speed on new testing methods and standards.

 

[Marmite]

Give this website a look. Lots of useful information and basic formulae.
Regards
Marmite

http://www.engineeringtoolbox.com/electrical-systems-t_33.html

 

[cuky2000]

Check the enclose site

http://www.hitechcontrols.com/pdf/T_Technical_Info/T097 Formulas of power engineering.pdf