Single phase is calculated:
Current in amps × volts ÷ 1000 = kva
3 phase is calculated:
Current in amps × line to line volts ÷ 1000 = kva
How to get transformer regulator KVA? i need to rewind the transformer, but the electrical workshop need this KVA to quote price. I'm new to this Westerbeke diesel generator. Model is 12 BTDC-514.
Single phase is calculated:
Current in amps × volts ÷ 1000 = kva
3 phase is calculated:
Current in amps × line to line volts ÷ 1000 = kva
12 kva is correct. You may discover that the transformer is marked on the bottom or backside also. Let me do a bit of research and I will get back to you.
Bob
A transformer regulator is a little thing. It can generally fit in the palm of your hand. Maybe a handful but about hand size.
If the transformer regulator in your generator has failed then buy a replacement unit. Its not something you would generally get rewound.
BTW, do you know its the transformer?
More often the bridge rectifier is what fails in a transformer regulator.
If you cannot find a replacement then goto a solid state voltage regulator. There are several off the shelf units that will work, but I really like the Marathon SE350. Basler also makes a great lineup of regulators.
3 phase power is calculated as:
Phase to phase volts * amps * the square root of three
In a wye connected system you can also use:
Line to neutral volts * phase A amps
+
Line to neutral volts * phase B amps
+
Line to neutral volts * phase C amps
These calculations result in Volt Amps
To convert volt amps to KVA or kilovolt amps divide by 1000
To convert volt amps to power multiply by the cosine of the phase angle.
Download the Technical Manual from the above site. It gives detailed testing parameters and procedures that should help you. You may want to also check the governor for proper performance. Utility power is only required to be + or - ten percent of the nominal voltage and you are outside of that range so there is most likely a problem with the transformer. Did you reinstall the shims exactly as they were removed?
Bob
I'm not very sure if this is the transformer regulator failure, but i need to check the coil rewinding due to i found corrosion at the transformer steel bar, shims etc and this make me curious about the transformer regulator condition and performance. FYI, in Malaysia its difficult to get the parts and will be so expensive. So, i decided to rewound.
Renewed the bridge rectifier, rewound the main stator and check the fuel pump + governor (still in good condition). Now my problem is, the alternator itself unable to achieve the useable output voltage when loaded. Without load output is 230 volt, loaded only with 1 acu 24,000 btu, suddenly output will dropped to 202 volt. Installed and test with AVR, the output is very constant at 230 volt even loaded with 2 or more acu. But can't afford the AVR cost, hope this make everything clear and i really need some advice on this problem. Thank you.
$50 you can buy a SE350 knock off on ebay.
Forgot to add this link:
http://www.westerbeke.com/TroubleshootingGuides/bt_12_stud_troubleshooting_manual.pdf
Yep, my first response when I get a call like this is generally RTFM