Stepper overvoltage?

[JayWal]

Hi, I'm working on a router to table conversion, have posted a few times asking questions trying to get it to work. Aaaaand I've got another question.

So I'm replaced all the electronics but kept the original stepper motors. I've found very little specs about the motors themselves in terms of input voltages they can take. Besides the vdc and amp rating on the motor, 1.78 and 4.67 respectively.

I found an article on power supplies on the Gecko site that said if you have no info on motors, if you multiply the vdc number in the casing by 4 that gives you the min voltage for the motor (7.7 in this case) and multiply by 20 for the max voltage (35.6 in this case).

When I first hooked up this drivers I used the original power supply from the router table which was reading around 50 vDC. Much higher than the 20x rule. I did get the motors to move, tho somewhat erratically. After 15 mins or so they stopped completely and no amount of tinkering has been able to resurrect them. When I power the drivers now (I've since switched to 24v) I still hear a click and the motors all lock up like normal.

What are the chances I fried all 4 of my motors, and that's why I haven't been able to get them to move since? Is there a way to test them?

Thanks for any info!

[acourtjester]

If you have a multi-meter (Ohm meter) you can check the motors out. Steppers have winding for both the step and direction attachments. there are 4 wire and 8 wire motors with the winding labeled like A- and A- each grouping of letters (A, B and so on) are a separate windings. You can use an Ohm-meter to see if there is a circuit for each, if you attach one lead of the Ohm-meter to each of the winding leads you should see a reading on the meter (max ohms is an open, not reading) if you don't see any reading on the meter when attaching to each wire of a winding it is open or non-functional (bad). The wires are color coded as to which winding they form A+ and A- is a winding. The click or holding action of a motor movement is only one winding both or all (if more then 2 sets of windings) are needed for the motor to work.

[JayWal]

Ok so both coils on all 4 motors read 0.6 on the meter. All exactly the same.

Since I don't have any info on the motors i did my best guess as to which leads are on the same coil. Found 2 wires that when touched together gave some resistance to turning the motor by hand. Those 2 wires I wired to A+ and A-. Then found the other 2 wires that did the same and wired them to the B terminals and just discontinued the 2 common wires (they're 6 lead motors).

[acourtjester]

I have not used 6 wire motor and the internet is hosed up now cannot check.

[robertspark]

Do your research, from memory the current with a 6 wire stepper is less when wired as a series arrangement.

I cannot check or link to documents now