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I have a project that currently has a standalone HMI/PLC installed and running on a machine. However, due to some layout modifications, it will now require an additional HMI for the second operator to interface with their "half" of the machine. Is there a way to "mirror" a second HMI so that I can use the existing PLC program and I/O wiring, and only duplicate the needed HMI screens for interaction? Maybe a "master/slave" relationship is a better way to state this.

My background is with Allen Bradley products, so doing this is not an issue. However, with the PLC/HMI all in one concept with Unitronics, I am not sure if or how this can be accomplished......

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  • MVP 2014

This topic has been of interest to me for some time, and I am currenttly helping a customer with a similar application.

Firstly there is no built-in HMI mirror function. This capability needs to be done manually in the program, however it is not so difficult.

I suggest using CAN as the physical layer. Unitronics have some nice features in CAN that will assist:

  • UniCAN protocol, which is fast and allows event-driven communications from both ends (compared with the polling that would be required for Modbus).
  • Programming pass-through, so you can program both PLCs by connecting into one of them.

You can export HMI screens from the original program to help create the slave, which can save you the trouble of re-laying the screens from scratch.

I hope this helps,

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Thanks Simon.

If I use the CANbus ISC protocol, it is my understanding that the SB200-SB215 bits are always transmitted (or active) to pass over the network. If this is true, and I only have limited bit data that needs to be duplicated on the slave HMI (operator indicators), and minimal manual functions to be sent back to the master for output functions, would this be the best way to accomplish my needs?

My thinking is that I can use the SB200-SB215 bits from the master as "virtual inputs" to the slave HMI for the indicators, and use the SB200-SB215 bits from the slave as "virtual outputs" to the master for the hard output control (manual functions).

What are your suggestions, and do you think this scenario is the best structure for what I am trying to accomplish.

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  • MVP 2014

With the structure you propose CAN ISC will be a simple solution.

Note that ISC is a cyclic communication:

When the data in these operands is constant (unchanging), it is broadcast every 400mS. When the data is dynamic (changing) it is broadcast at a rate not exceeding 20mS. Even when the data changes are rapid, data is not broadcast at a rate exceeding 20mS; this avoids network overload.

You are effectively treating the slave HMI like a remote I/O block, by using a separate block of registers for "in" and "out". I have thought through another situation where the slave is more tightly integrated and writes directly back to the active registers in the master program. In both cases it is necessary to consider the flow of data between the master and slave. If either master or slave can control the system, it is essential to make sure they are both operating on the most up-to-date data, and that edits on one side are not overwritten with old data from the other side.

It seems to me that either:

1. you use CAN ISC and write code in the master (and/or slave) that ensures the consistency of the data. This means controlling when the data is read to or written from the CAN ISC registers.

2. You use UniCAN and only send data in either direction if there is a change.

So, for a simple system as you describe I think CAN ISC will be fine, and the logic to ensure no data conflict will be reletively simple.

However for a more complex system, it may be an advatange to use UniCAN, and a commuincation structure similar to that used with the EX-RC1 expansion module.

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  • 6 years later...

I have Micrologix 1400 plc connected to Omron NS10-TV00b-V2 HMI. Micrologix 1400 has two serial ports (RS232/Rs485 isolated and 232c non isolated port). I want to connect second Same HMI(exect Mirror) to the PLC. what hardware will I need? 

Omron HMI has two DB9 serial portA and Port B. And PLC has 8 pin Mini (RS232/Rs485) and DB9 (232) port. Also both has ethernet ports too.

Currently 8pin Mini from PLC connected to one omron HMI Port A.

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9 hours ago, Hasmukh said:

I have Micrologix 1400 plc connected to Omron NS10-TV00b-V2 HMI. Micrologix 1400 has two serial ports (RS232/Rs485 isolated and 232c non isolated port). I want to connect second Same HMI(exect Mirror) to the PLC. what hardware will I need? 

Omron HMI has two DB9 serial portA and Port B. And PLC has 8 pin Mini (RS232/Rs485) and DB9 (232) port. Also both has ethernet ports too.

Currently 8pin Mini from PLC connected to one omron HMI Port A.

Where is the relation with Unitronics

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  • MVP 2023

@Hasmukh - Kudos on your chutzpah posting an AB question on the Unitronics forum.  You realize Unitronics has more bang for the buck than AB, right?  😁  And an Omron HMI?  That's just painful.

You should be able configure both serial ports as DF1.  

Years ago I had to make a SLC 5/04 with only one port talk to two HMIs.  The port mux I used is no longer available, but what you're looking for is a "serial port multiplexer". 

You could pony up the cash for one of these-

https://www.prosoft-technology.com/Products/Gateways/DF1-Master-Slave/DF1-Serial-Port-Expander-Gateway

I also found this-

https://www.conferenceroomav.com/kramer-/vp-14.cfm?gclid=Cj0KCQjwyoHlBRCNARIsAFjKJ6AxlKz6kFB4Wz9GMkwcu4BAH3B4CcTiddT_ms7-RxFUpNEXpuNvzQ0aAlpIEALw_wcB

 

Joe T.

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19 hours ago, Joe Tauser said:

@Hasmukh - Kudos on your chutzpah posting an AB question on the Unitronics forum.  You realize Unitronics has more bang for the buck than AB, right?  😁  And an Omron HMI?  That's just painful.

You should be able configure both serial ports as DF1.  

Years ago I had to make a SLC 5/04 with only one port talk to two HMIs.  The port mux I used is no longer available, but what you're looking for is a "serial port multiplexer". 

You could pony up the cash for one of these-

https://www.prosoft-technology.com/Products/Gateways/DF1-Master-Slave/DF1-Serial-Port-Expander-Gateway

I also found this-

https://www.conferenceroomav.com/kramer-/vp-14.cfm?gclid=Cj0KCQjwyoHlBRCNARIsAFjKJ6AxlKz6kFB4Wz9GMkwcu4BAH3B4CcTiddT_ms7-RxFUpNEXpuNvzQ0aAlpIEALw_wcB

 

Joe T.

Thanks a lot Joe. I appreciate for sending me some suggestions. I always have feeling that some  go extra miles to help people.

Thanks again.

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