Would someone be able to explain how much current each stepper draws when wired in series? The firmware allows up to 2amp but I always see 1amp recommended. Is this because there are the two steppers both drawing 1amp each from one driver making it’s max rating of 2amp?
I’m thinking of buying a SKR 1.3 with TMC5160. The TMC5160 is rated to 4amp, my stepper motors can be set to 2amp and im interested to see if the extra torque will help.
Would 2 steppers set at 2amps in series draw 4amps total?
When wired in series they get the same current, which is the same that the driver supplies, so if the driver is giving 2 amps then both motors get 2 amps.
Running motors near their rated current will make them get hot, which can melt plastic parts and eventually cause the motors to fail. Running motor drivers at their max rating will cause the drivers to get hot. The drivers dont generally fail as a result but they will go into thermal shutdown to save themselves. Thermal shutdown can be catastrophic to your cnc job.
I am finding 70% is about as high as you can go for long periods and keep them under 50C. That max amp rating is for short bursts and not long periods.
When you say 70%, is that 1.4amps on the Mini Rambo? I tried setting them to around that recently and once the operation was finished and they were sitting there energised but not moving I could hear them skipping steps for some reason.
Just make sure they are under 50C after they have been working for more than 30 minutes in a warm environment. Yes 1.4amps out but some steppers are overrated. Do not blindly set things without checking temps frequently.
If they are not moving they can not skip steps. Do you mean a small high pitched hum, that is normal.
