# Sabertooth which?

Hi!I have two 250 watt motors (450 watt stressed) 25a x 2 32x 2 or 60a x 2 which?

I require your help regarding a problem I’m encountering.

Description:

Hardware concerned:

Software concerned:

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Hey @donn!

What voltage will you be running your DC motor at (assumed DC, please confirm)? Are you running at constant speed (i.e.: voltage) or will you be managing its speed by varying the input voltage?

Some quick “back of the envelope” style calculations can help here. Lets figure out the minimum voltage to not stress/damage the DC motor controllers you mentioned.

At 450 Watts of total peak power and assuming 10% buffer for safety, so 450 x 1.1 = 495 W, or lets say ~ 500 W.
So, for 500 W, with:

• 25 A: 500 / 25 A => 20.000 V DC.
• 32 A: 500 / 32 A => 15.625 V DC.
• 60 A: 500 / 60 A => 8.333 V DC

If you are using 12 V DC for this motor, I’d recommend going for the 60 A version of the Sabertooth.
If running at 24 V DC, the 25 A should work but I’d recommend the 32 A one just to be on the safe side.

I hope this helps!

Sincerely,

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