analog output

[TozoM8]

Here is my next challenge. I am running a V1210 with V200-18-E3XB on my industrial washing machine. I use one analog input for the scale to load the machine and it works perfect. The operator enters how much they want to load into the machine (400lbs) and when they load the silo that feeds the washer stops at 400. When the washing is finnished the material goes to another machine (dryer) that also has the same PLC setup.The two machine runs on a different 24V power supply, but it could run from the same if that helps. The wet material that goes into the dryer silo is around 30% heavyer. How can I set the dryer silo scale to turn off at 520lbs, 30% higher than the washer setting? I was thinking to setup an analog output from the washer plc to the dryer plc as an analog input then linealize it to ad 30% and store it as load limit. This way when they change the load limit in the washer it would automatically tell the dryer how much material it should get. The problem I see with this idea is that I am using the acm and T+ from the scale amplifyer. Connecting an analog common from a different source could be a problem that could screw up my scale reading.

[Eyal Koren]

Hi.

There are several ways to communicate between Vision PLC's, but using analog I/O's is not one of them (at least not a recommended one).
I have a solution for you, based on the following assumptions:
1. Both machines are'nt very far from each other.
2. The PLC's doesn't include the Ethernet module.
3. The industrial machines generate EMI in some level that might interfere with the normal PLC's operation. If these assumptions are correct, i would recommend connecting both PLC's via Modbus over RS485 cable. It is relatively immune to noise and You can define it easily in Visilogic. Define the washing machine PLC as Modbus master, and the dryer PLC as Modbus slave. When the operator input the weight load (on master PLC), send this data to the slave PLC and multiply this value by a factor. I attached to this post two Visilogic application (Modbus Master & Slave). These applications are for V130 but hey demonstrate exactly what you need to add to your application. I also attached a PDF taken from Visilogic help file regarding RS485 network setup.

 

Hope this helps. For any questions feel free to contact me.

V130_Modbus_Master.vlp

V130_Modbus_Slave.vlp

RS_485.pdf

[TozoM8]

Thank you for the help. They both have ethernet card installed because in a future (when I figure it out) they have to report production data (cycle count and material/sope usage) via email to the production supervisor.

[Eyal Koren]

That makes it even easier.

Connect both PLC's to an ethernet cable (in the future you can add a switch to the network and establish data reporting via mail server).

Define the washing machine PLC as TCP master (the same socket will later be used for sending emails) and the dryer as TCP slave.

When operator input the desired weight on washing machine, send the desired value to the dryer (via TCP RAW function block), then send feedback back to the washing machine to close the connection.

I attached a short summary about Ethernet TCP in Visilogic.

 

Ethernet_TCP.pdf

[Flex727]

 

Connect both PLC's to an ethernet cable (in the future you can add a switch to the network and establish data reporting via mail server).

 

 

Without a switch it will need to be a crossover cable, won't it?

[TozoM8]

Thank you!

[Eyal Koren]

Without a switch it will need to be a crossover cable, won't it?

 

Flex727

By Ethernet over twisted pair standards, to directly connect two devices you should use a crossover cable.

However, I mentioned the use of a network hub (switch) for the future implementation of data reporting via email (connecting the network to the internet).