DB 25 Connection Options

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Gary Campbell
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DB 25 Connection Options

Post by Gary Campbell »

All drives are not created equal. The signals that they require vary in voltage (5-25vdc) some sinking and some sourcing, some with rising edge, some falling, the list goes on.

In my case I was using a new model of closed loop drive from Leadshine, the CS-D1008. It stated a logic voltage of 5-25vdc. Once I had them running I tested them using 3 connection methods. 1) 24vdc logic using the board terminals and schematic for similar 24v drives. 2) 5vdc logic using the board terminals and the Leadshine DM series schematic and 5v power applied after the BBG had booted. 3) Using the signal out from the onboard DB25 connector.

The 3rd method proved to be the most compatible signal for my drives, but since many out there will find difficulty making connections to a DB25 connector, I made a video showing a few different methods to make these connections of step and direction signals to your drives.

https://youtu.be/TLOtXTOSUWo

Note: If you feel you are having issues, test using one or more of these methods, using straight and inverted signals for each.
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cncman172
Posts: 254
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Location: Westerville, Ohio

Re: DB 25 Connection Options

Post by cncman172 »

Gary,
Nice video. I had this same issue, but the root cause was the DB25 connections have pull up resistors, where the terminal strip connections do not have the pull up resistors. This causes problems if you fail to add the pull up resistors. I was driving some differential drivers and was missing steps, so it was difficult to troubleshoot. I even did a hybrid approach and used the enable signals from the terminal strip and the step and direction from the DB25 and it works perfect.

Russ
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