Tags on Panelview plus to compact logix losing comms

I have a panelview plus that is connected to a compact logix. I use this as the DCS for a gas fired heater sometimes even though the controller and the hmi are on UPS power the HMI will lose connection to the Tags in the controller its a simple fix to just reboot the panelview plus my question is why is this losing its tags? the system is static IP and on a local network switch in the same enclosure.

The first thing I would do is check the CAT5 cables and replace the switch.

It stays connected most of the time I want to know why it doesn't just reconnect automatically being that it is a static IP

Even if you unplug a cable and plug it back in, or cycle power on the switch or PLC, it should immediately start talking again. You shouldn't have to cycle power to the HMI, and that's any HMI from any manufacturer using any protocol I have come across (so far - I am sure there will be one different)

I would see if the ether net switch is still powered when on the UPS
I have seen that before if the switch is not powered no communications

The HMI should automatically connect to the tags inside the compact logix controller is there a settting inside the panel view plus that I need to check so it automatically connects to the tags? Ive set the HMI up to use the static IP address of the controller so it should look at those tags as soon as its done with its boot sequence. But occasionally the graphics on the HMI will not connect to the tags in the controller and they show up as error. Am I missing a setting somewhere?

As soon as the switch is communicating and both the PLC and HMI are powered the HMI should start comm's with the PLC without intervention. I still would suspect the switch.

I've seen situations where the Panelview Plus would not be able to reconnect once a problem occurred. This was a few years ago with the PV+ 600. I worked at a company with some machines that had to be locked out for minor adjustments. They got tired of waiting for the PV+ to boot up so they could start the machine. The adjustments take 10 seconds, the boot time is over 90 seconds. So they installed battery backups in the HMI panels to keep the Panelviews "alive" for up to 10 minutes in hopes that they could gain production by not having to wait. At least half of the time, the panelview communication would not recover and they would have to call maintenance to open the panel and power cycle the HMI to get comms restored.

There is likely a real problem with a cable, the switch, or some interference but the fact that the Panelview Plus doesn't recover on its own when things are good again does not surprise me.

That sounds like the exact same problem I am having with the HMI screen was there ever a fix for the comms not reconnecting

speaksy87 said:

That sounds like the exact same problem I am having with the HMI screen was there ever a fix for the comms not reconnecting

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If you need to power down the PLC or network gear then power down the HMI too.

If the problem crops up when everything is up and running, I agree with what others have suggested: replace the Ethernet cable and/or the network switch.

I didn't see problems when everything is in good working order and powered up.

the reason I would check the power to the Ethernet switch is that is common to put the PLC and the HMI on a ups but forget to add the Ethernet switch to the UPS. So when the system is switched over to operate on the UPS the power to the switch is lost

What model number and firmware version?

If you have many controller scoped tags in your PLC, that can cause delays in connecting.
It used to cause reconnect issues, but I thought those were fixed.