Jump to content
Sign in to follow this  
Paul Rylatt

Expansion module extender cables

Recommended Posts

When using the EX-A2X or EX-RC1 with a Visilogic PLC, it is required to put all 8 expansion modules in a row.  This can require a very wide back plate and is not very feasible for projects with a small cabinet footprint.

Is there any thought to creating extension cables that would allow the expansion modules to be placed in multiple rows on a back plate?

Share this post


Link to post
Share on other sites

Unitronics' official position is you can not extend the I/O bus.

We have made an "unofficial" 36" extension cable with shielded flat cable that we sell.  It seems to work.

Send me a message if you're interested in one.

Joe T. 

Share this post


Link to post
Share on other sites
On 2/8/2019 at 4:45 PM, Joe Tauser said:

an "unofficial" 36" extension cable with shielded flat cable

I have often pondered that solution, wondered why "it is not recommended" and never actually built and tested for myself because I had thought it was 2 things:

1).  due to power required needing more than a ribbon...perhaps the actual main power lines augmented would help?   and

2).  the overall question of how does the plc work out where I/Os are anyway.  Does anyone know (apart from the creators!) the intricacies of this bit of trickery?

If your cable works, Joe, that is worth knowing.  I have had numerous instances of exactly Paul's problem.

cheers, Aus

Share this post


Link to post
Share on other sites

I tried to investigate how the expansion adapter EX-A2X bus was built. Standard CMOS logic push-pull output with 5V power supply used.

So I think that it will work through a longer shielded wire. Especially if the expansion units are placed in a metal cabinet.

Also, I encountered the option of placing expansion blocks on a metal plate similar to the additional door.
The blocks were placed on both side - half stood on the rail in front, and half behind. Long extender is not needed in this case.

I liked the access that provided the folding door in the cabinet. But maybe in small box this method it is not applicable.

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×