View Full Version : M542 driver (Zapp) half or full current?

02-06-2010, 10:10 PM
Using a 3nm stepper from Gary with the above driver powered by 2 ps407 power supplies in series. Anyone know the correct dip switch position for switch 4? Off is half current, on is full current.

Reason I ask is all the drivers I bought from Zapp before came setup with switch 4 off but this one came with it on and having no idea what position it should be in plus my legendary smoke releasing skill, I thought I'd better enquire.....


02-06-2010, 10:39 PM
sw4 in the off position supplys 50% current when the driver is idle and full (selected) current when active , reducing heat in the stepper
sw4 in on position supplys full current idle and active

i have mine set to off works fine

02-06-2010, 10:56 PM
Yes, I'd leave it at 'off'. About the only time you might want it on is if the stepper is supporting a heavy spindle motor on a high-lead ballscrew z-axis where the torque at 1/2 power might not hold the spindle up!

03-06-2010, 07:23 AM
Also dont power up with the two power supplies connected in series, that will give it 80V.
Connect the power supplies in parallel.
Connecting in series will add the voltage of the power supplies together, connecting in parallel will add the current of the power supplies together.
you need more current not voltage.

03-06-2010, 08:20 PM
Sorry, I meant parallel :heehee:

This is for my A axis and the machine has been running beautifully for nearly two years now so I must have got the wiring right

Cheers guys, thanks for the help.

04-07-2013, 08:16 PM
Hi guys just out of curosity whats the difference between parrell and series, thanks

Clive S
04-07-2013, 10:28 PM
Unless you're not joking connecting in series is like a daisy chain and connecting in parallel like connecting side by side ie +v to +v and -v to -v ...Clive

04-07-2013, 10:33 PM
In series you get all the torque at the low speeds, but the torque will drop off very fast if you run the motor fast.
Parallel due to the lower inductance will give you a much better performance at the higher speeds, but will be slightly lower torque at the lower speeds.

05-07-2013, 06:40 PM
Thaks guys ill have to have a look and see which way i have wired mine, thanks again

09-07-2013, 09:02 PM
Hi guys i have rewired the motors to parrell. Thanks