# Rated watts on grinder, how true?



## froggystyle (Oct 30, 2013)

Testing the watts my macap mc7 pulls when grinding, plate states 800 watts, but when plugged in the max i get when grinding beans is only 550 watts.

Trying to work out at what point it would jump up to 800 watts, tried it under load, is it just the manufactures playing safe??


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## GrahamS (Aug 27, 2015)

How are you measuring the watts?

It could be that the motor in it is rated at 800W, but the load the machine can usually put on it is only 550W.

I would say. does it matter, but it obviously does, because when we look at specs we know a 800W grinder is better than a 500W one.


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## Nikko (Aug 20, 2014)

You say you measured 550W. I take it you mean consumed power. Did you actually measure W or VA? In order to measure W you also need to measure the power factor.

The motor rating is the maximum load the motor can deliver, either continuously or for a specified duration as stated on the plate.

These small motors are very inefficient so what a motor takes and what it delivers are very different.

The motor will deliver whatever it takes to spin the burrs. Irrespective of its rating. In my experience, a typical motors takes about 150W per gram/sec of output. That is consumed Watts; the delivered mechanical power will be much less.

As long as the motor is powerful enough to start and spin the burrs without overheating, then that is all that is needed. A more powerful motor *w**ill not* be better but will consume more because it will be less efficient.


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