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harbertor
14-01-2004, 02:28 PM
Hello;

I´ve been told that an electrical motor working at sea level gives a capacity 37 kW, but working 3000 m. over sea level gives 30 kW

Could anybody explain why?

bye

Peter_1
14-01-2004, 02:41 PM
New nature laws perhaps? I should say, impossible.
In the formula for power, you don't find any parameter such as density, temperature, humidity, pressure...

But,... it is true for combustion engines. Performance decrease for combustionengines with altitude.

harbertor
14-01-2004, 02:48 PM
and if the electrical motor is in a different country such as Chile (may be with different voltage valeu and/or frecuency) where it produces 30 kw and working in a European country at sea level produces 37?

chemi-cool
14-01-2004, 03:30 PM
hi harbertor,

an electric motor will give the same output every where.
maybe whatever this motor have to turn will have difference resistance from sea level to 3000m.

chemi

Peter_1
14-01-2004, 09:01 PM
I should even say, the higher you go, the less air particles/molecules, the less resistance you will encounter.

PobodysNerfect
14-01-2004, 11:14 PM
The power rating for the motor is reduced if the motor is for high altitude, due to the less dense air and therefore the reduced cooling.
Anyway, I would expect the change of altitude would have an effect on the magnetic field, as air is a bad conductor for magnetism, so maybe (just maybe) the motor would run with a higher efficiency.
Saludos
Jan

lin
15-01-2004, 01:34 AM
Saludos
I agree with u for the motor cooling.
but for the magnetic conductivity, i think they are same even in vacuum.

PobodysNerfect
15-01-2004, 05:49 PM
Lin, your quite right, the magnetic permeability of air and vacuum is the same.
Saludos
jan