Logo X70 interface extension cable

Hello, 

Short version: What is the LOGO!8 X70 interface that the LOGO base unit uses to connect to other units (for example Digital I/O and Analog I/O units)? Is there any official cable I can use for it? 

Long version: I have designed a device using LOGO! 8 for a customer. The device fits in a cabinet. I know you can extend the LOGO! by mounting Digital and Analog I/O units side by side the base unit using the interface referred to as X70 in the base module. I have done it before and it works very well. The issue is that my customer would prefer the extention units to be placed in a separate cabinet, so he can keep the base cabinet as a standard and sell the extention cabinet separately. Is there a way to connect the logo Base Module to the extention modules via a cable instead of mounting them side by side?

I've tried to read in the LOGO! manual but I haven't found much info on this X70 interface. Anyone of you knows more? Thank you?

Hello jonian,

look here

Thank you for your answers! I had no idea the supply voltage was part of that bus... which makes more questions/considerations come to my mind:

1. so the expansion modules are powered by via the base module already? Then why do they have their own L+ and M terminals? The AM2 even has two of each, which already made me a bit confused the first time I saw it, but I thought maybe each analog input could potentially have its own supply... I have connected +24V and GND to all of those terminals, so it looks like I have a lot of unneccessary cabling in my device :D

2. still curious to know what kind of interface is being used to communicate between the modules.

3. I get what they're saying in the video, but it's not ideal in my use-case. In addition to using a bigger LOGO! Base Module in the extension cabinet, I would also need to add an Ethernet switch in my original cabinet, since I already used both of the available Ethernet ports in the TDE. I agree with you that a cable would not be suitable if I had 230V LOGO devices, but since we only use 24V DC and we have full control of the cabinets I am still tempted to use a cable. What I was originally concerned about whas if adding a cable would add disturbances to the communication and make the LOGO operation more unstable.

Thank you again for your enlightening answers!

The internal ic power is connected, i think at the positive line, about +10V. The units need its own power connection for the edge electronics.

In the long past i have connected a 230Vac type extention to a 12Vdc extension and it works as long you don't have any other galvanic connection. This is very hazzardous though and i will never do that again or recommends that.

One mistake or grounding connection and you blow up your modules or have a potential live risk. (230Vac on your 12Vdc lines)

So there are very good reasons why there are no connection cabels avaliable. And why the mechanically pins prevent connecting different power types. 

JdZ

In the long past i have connected a 230Vac type extention to a 12Vdc extension and it works as long you don't have any other galvanic connection. This is very hazzardous though and i will never do that again or recommends that.

One mistake or grounding connection and you blow up your modules or have a potential live risk. (230Vac on your 12Vdc lines)

So there are very good reasons why there are no connection cabels avaliable. And why the mechanically pins prevent connecting different power types. 

The developers of the logo have already thought of how to make it safe. Any tinkering (including changes) to these devices must therefore be avoided and is life-threatening!

Greetings Ella_68