When buying a CNC power supply....

[SwampDonkey]

Does the amp rating of the supply need to be greater than the sum of the amp ratings of the steppers?
So, say we have 3 stepper motors with 3.5A ratings each, does the power supply need to be able to crank out 10.5A?

[hndswthtshdws]

General rule of thumb is 0.6*(sum of all motor amps).

So 6.3a is the minimum.

[HorridHenry]

Does the amp rating of the supply need to be greater than the sum of the amp ratings of the steppers?

Rule of thumb......get the max amperage PSU you can afford as the drivers will only pull what they need when working,plus you never know when you might add a 4th axis?