Jump to content

Recommended Posts

Hi guys,

I'm thinking of buying the following 3-axis stepper motor kit from ebay.


I will not use the breakout board included in the kit but i wil use a Unitronics V350-35-TR34 instead.

My application requires simple, not very accurate positioning of 3 axes.

My questions are the following:

The driver accepts pulses of 5VDC while the PLC HSO is 24VDC. How can i convert the high frequency pulse to 5VDC?

Also the Pulses are NPN type. Is this a problem for the driver?

Thanks in advance

Link to comment
Share on other sites

  • MVP 2014

My brief comments as follows:

* the NPN outputs of the TR34 are an advantage when working with your 5V signal, as they will work with switching voltages as low as 3.5V (p4 of Spec Sheet)

* you will need a 5VDC supply (for example a regulated plugpack (what Australians call them) or "Wall-Wart??" (what the Americans call them))

* The wiring details for the stepper driver are a bit vague, but looks like the step and direction are opto-isolated. Assuming this is the case, put 5V direct from the supply to the (+5) terminals of the inputs, then wire the (-) terminal of each input to the PLC outputs, then connect PLC common to 0V of your supply (and link with 0V of your 24VDC PLC supply).

I hope this helps, and please note my assumptions.

You may be able to get more detail direct from the stepper suppliers own website.

Link to comment
Share on other sites

  • MVP 2014

I took a look at the installation guide for the JZ10-11-PT15. It's a bit of a grey area but I would suggest the following:

* the above specification that you quote (20.0-28.8VDC - which is 24VDC +/- 10%) relates to the power supply requirements for the output supply terminals at the right-hand end of the output terminal strip. This is the power required to drive the relays, and is the reference for the PNP solid state output.

* If you look at the wiring diagram for the NPN output, you can see that the above 24V supply is not referenced, and a separate "+Vnpn" supply is reference instead. This "+Vnpn" would be your auxiliary 5VDC, and also connect the 0V of the 5V supply to the 0V of your 24V supply.. The on-state voltage of the npn output is 0.4VDC, so it should work.

* note the lower frequency of the Jazz output compared to the V350-35-TR34, of 32kHz in NPN mode, when driving a resistive load.

As you can see there are a few maybes. If you want to be sure before purchasing the unit i would forward the question to your local supplier and/or to support@unitronics.com

Link to comment
Share on other sites

Thanks again for the feedback.

I was thinking of connecting a 2k/1w resistor in series with my PLC NPN output and connect it with the (-) pulse input terminal of the stepper drive.

Then connect +24VDC directly to the (+) pulse terminal of the drive.

The input is opto-isolated.

Should it work this way or not?

Link to comment
Share on other sites

  • MVP 2021

I have connected a stepper driver in exactly the way you describe and it works fine.

Let's look at the design specifics-

Your control specifies a 5V input pulse, which is extremely common. It has an internal resistor in series with the opto-coupler to limit the current to about 10 mA at 5V. As Simon mentioned, the on-state voltage drop of an NPN output is 0.4V, so we can effectively ignore it. The voltage the resistor will need to drop is 19V at 10 mA, resulting in a series resistor size of 1900 ohms, or the 2K you mention. The power rating of the resistor is 0.2W, so you really only need a 1/2W resistor.

If you can locate a 2K resistor, great. A 2.2K is much easier to come by and will result in slightly lower current through the opto-isolator but it will still work. This is the value I use.

Joe T.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...