1 Project but 2x V1040

[mckruger]

Good Day

 

Scenario :

1x vehicle fitted with 2x V1040's

 

What i want to know is if i have a door sensor for example, i would have to take a wire to an input on both V1040's to get them to both see that the door is open.

As 1 V1040 will be in the cab and the other at the back of the vehicle.

 

Is there not a way to get the 2 V1040's to talk to each other so that i only need to wire to 1 V1040's input and for the other V1040 to see it  ?

[Cara Bereck Levy]

Hi--is this connected to the J1939 question you asked earlier? 

[mckruger]

Hi--is this connected to the J1939 question you asked earlier? 

This goes with that system but these are normal 24v positive/negative signals that are being sent and received, not working on J1939

So essentially its a different question.  

[Kikis]

Hi mckruger,

 

You can use modbus RTU to communicate with the 2nd V1040.

It's very easy, just spend some time to watch the Unitronics webinar about Modbus.

http://www.unitronics.com/support/webinars/modbus

[mckruger]

Hi mckruger,

 

You can use modbus RTU to communicate with the 2nd V1040.

It's very easy, just spend some time to watch the Unitronics webinar about Modbus.

http://www.unitronics.com/support/webinars/modbus

Thanks ive gone through that webinar.

Going to try and figure out instead of writing a value to a textbox i would like to switch on a output or read an input.

[Simon]

I might be coming in a bit late on this one, but I prefer UniCAN to link the PLCs in this way.  The main advantage is that UniCAN can be event-driven from either end.  Modbus must be polled using a master/slave arrangement.  With UniCAN either PLC can send changes to the other PLC as soon as something happens.  Also the CANbus hardware is on the V1040 PLC as a built-in option, which leaves your serial ports free for other uses.

 

On this final point I am willing to be corrected, but I also think the CANbus physical layer is slightly easier to deal with than RS485.  Just follow the rules, use the proper cable and it usually works.  RS485 works well once it is up and running, but can be difficult to figure out initially.

 

As with Modbus, there is a webinar:

http://www.unitronics.com/support/webinars/canbus-unican

[mckruger]

I might be coming in a bit late on this one, but I prefer UniCAN to link the PLCs in this way.  The main advantage is that UniCAN can be event-driven from either end.  Modbus must be polled using a master/slave arrangement.  With UniCAN either PLC can send changes to the other PLC as soon as something happens.  Also the CANbus hardware is on the V1040 PLC as a built-in option, which leaves your serial ports free for other uses.

 

On this final point I am willing to be corrected, but I also think the CANbus physical layer is slightly easier to deal with than RS485.  Just follow the rules, use the proper cable and it usually works.  RS485 works well once it is up and running, but can be difficult to figure out initially.

 

As with Modbus, there is a webinar:

http://www.unitronics.com/support/webinars/canbus-unican

Thanks,

I have watched the webinars on the UniCAN and its what i was looking for.

Although i still need to study it and learn how to apply it to my project.