Welder Generator as a Dyno?

[WhackyWheels]

I've been given 3 old welder generators (W/G), and I was told that they could be used as an "Electric Dynamometer" to measure I.C. S.I gas engines, specifically Moto-Cross (dirt bike)engines.
Is this possible? And if so, beside the W/G, what else would I need to build one?
The W/Gs are rated at 180, 300 and 500 amp respectively.
I don't have a lot of money, but I do have a lot of available time to work on such a project.
If anyone could help with any technical information on how to make one of these things I would be in great appreciation.

Thanks for any help.

 

[jbartos]

Suggestion: In principle, they may be used as dynamometers. The major task will be to have them properly calibrated to measure the shaft torque, horsepower, etc. An RPM meter will also be useful. Also, visit

http://freespace.virgin.net/dyno.power/

http://86.1911encyclopedia.org/D/DY/DYNAMOMETER.htm

http://www.awdynamometer.com/

etc. for more info. There are many web sites covering dynamometers.

 

[redtrumpet]

jbartos - I believe dynamometers measure torque and rpm and the horsepower is calculated.

 

[jbartos]

Suggestion to the previous posting: Visit

http://www.solution.com.my/images/new pdf/th03.pdf

for the dynamometer output variables. Among others stated are the dynamometer output voltage and current. By adding multiplier, one can obtain Watts and Horsepowers, which could be in agreement with your statement that HP are calculated. It just depends on instrumentation and metering.

 

[WhackyWheels]

Thank you very much for this information.

I have no illusions regarding how labor intensive this project will be. For that reason, I will continue to further my information search in hopes to find an example that closely represents the dynamometer project I'm working on.
However, I am realistic that there are not many people with the same objective in mind.
Any further or descriptive input would continue to be greatly appreciated.

Thanks again,

Pitot

 

[cbarn24050]

Hi, wouldn't it be easier to run your dirt bike up a hill and measure it directly?

 

Great idea and should work, but. I think youll have problems with the high mass of the wg rotor and peaky PB of the smaller 2strks. If you search the web I ll bet you can find a cheap dynomite water brake. Ive seen the earlier series units go for as little as 800 bucks with the instruments/reader. Alot of hobby racers but these things and dump'em after they find out what a headache they are.