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mike
Feb 16, 2005, 01:11 AM
Does anyone have any opinion on those things usually called motor testers or
motor checkers (or sometimes called poor man's dynos, althought they are not
even that really) ??

I would be interested in knowing if anyone uses one? How do you interpret
the data? What are the important metrics? Amp draw? Is higher better or
worse? Do you look at Amp draw per RPM? Or amp draw per volt?

Or indeed are these things any use at all?

MIKE

Chris Dugan
Feb 16, 2005, 05:11 AM
> Does anyone have any opinion on those things usually called motor testers
or
> motor checkers (or sometimes called poor man's dynos, althought they are
not
> even that really) ??
>
> I would be interested in knowing if anyone uses one? How do you interpret
> the data? What are the important metrics? Amp draw? Is higher better or
> worse? Do you look at Amp draw per RPM? Or amp draw per volt?
>
> Or indeed are these things any use at all?
>
> MIKE
>
>

They're only really useful for running in brushes and checking the brush
condition (which you can also do visually by looking at the sparks generated
and comm condition), I wouldn't put too much stock in the no-load RPM and
Amp draw as in your car they'll never reach that speed.
I get a better idea of how punchy/mild a motor is by just connecting it
briefly to a fully charged battery for a second to test the spin up and feel
the torque by hand.
As an example a Trinity P2K2Pro will draw about the same current as say an
Epic at full revs but have quite a bit lower RPM, in the car gear them
properly the P2K2 will pull better out of the corners and leave the Epic
behind but on a fast open track the Epic will be in it's power band coming
out of the corners and leave the P2K2 down the straight. It's all to do with
power bands, the P2K2 has it's lower down the RPM range than the Epic will
do.

Chris