Flex727

To my understanding (which admittedly may be totally wrong), the HMI updating is independent from the PLC CPU. One would think that would be an advantage, but I have found that the UniStream HMI processing to be very poor compared to, for example, the Vision PLC which runs everything off a single, slower CPU. I would love for one of the creators to explain this.

May I ask what your concern is? PLC applications rarely need that to be of consideration, especially with the UniStream line, which is extremely fast for a PLC.

Initialize merely clears out all operands (assigns the value zero to numeric operands and resets bit operands to off). Normally, this will not affect communications, but will not hurt anything. If the running program has power-ups, then that power-up value will be assigned immediately when the PLC returns to run mode.

1. Done that - nothing found. 2. This is a personal laptop, no proxy servers. 3. I was connected directly to the PLC via crossover cable. No network, no wireless connection. 4. I should have tried to ping that address. Rats. 5. It's a laptop. It gets rebooted every time I use it.

No, I have to use static specs for this job as the customer has assigned .062 subnet to our systems.

No.

Yes it can. Will do.

I get that, but what's with the 192.168.50.208? There's no .50 subnet in this network.

It's a V700.

Perhaps not strictly a Unitronics thing, and likely there's something I don't understand about the PING function, but often when I try to Ping a Unitronics PLC (connected directly to it from my laptop) I'll get this strange response (see screen cap). Notice the laptop IP address is 192.168.62.251 and the PLC IP address is 192.168.62.208. However it tries to Ping 192.168.50.208. What is it trying to do here?

Yes.

Just a couple of comments: - You don't need SB 1 where you have placed it. - Do NOT place multiple unconnected logic threads in a single ladder rung. - Your timer will count 30 seconds one single time then the out bit will stay on as long as the PLC is powered on. Is that what you want?

Thank you!

Yes, but I was referring specifically to this scenario: Two (or more) Vision PLCs communicating with each other using UDP. On that same network (and same subnet), other devices are communicating with each other using TCP. No problems or conflicts?

@Gabriel Franco I have been told that other devices using TCP on the same network presents no conflict and that both protocols can coexist simultaneously without problem. Can you confirm that to be true?

You need a RESET of MB 5001 immediately after the Connect FB.

My apologies, I was still thinking about the previous comment mentioning Samba and posted the VisiLogic Help file.

Sure there is:

I always display the PID Status integer on screen, usually on the PID setup screen.

It would depend on the slave device. Normally there is no need to disconnect the socket ever when you are engaged in continuous transfer of data. That's because the logic you are using won't work (assuming the disabled rung 3 in the ModBus subroutine). You are Setting MB 4024 again immediately after it is Reset in rung4 which then attempts to perform the R.I.R function which will exclude the P.H.R. function later in Rung 6. Also: - Please do not have multiple logic threads in a single ladder rung. - Instead of dozens of Sets & Resets, use vector operations when addressing is sequential.

No, when you release I Button, power flow to O Outstate is discontinued immediately. Break your logic up into two ladder rungs and it will work. Understanding power flow is essential to ladder logic. Edit: I see you may be fooled by ButtonState.Out being red. Don't be - that's only showing you that if there was power flow to the bit then it would continue on to the coil, but since there is no power flow to the bit, there is nothing to transfer to the coil.

As I said, you need to review the example projects that came with your VisiLogic installation. You are using poor form for your MODBUS communications. That said, it appears your problem is MB 4010. It looks like that should be a direct contact, not inverted contact.

I have to dash off or I would look at this in detail. For now, I'll say review the example projects that came with your VisiLogic installation and follow the programming form laid out there. No. This is common. Unitronics starts their addressing at zero, many other devices choose to start at one.

Did you try version 1.33.236? It may work.

Contact support. They should be able to supply it for you.