I am getting intermittent red overlays on my HMI screens. What settings can I adjust to allow more time for data to be polled before the overlays show up? It seems that the communications to my PLC is fine- a continuous ping does not show issues and RSLinx is not reporting any read/write failures. We are using RSLinx as the OPC server for our custom software package, but the Ignition screens are using the internal OPC-UA server.
Log into the Ignition Gateway Configuration and select OPC-UA > Settings. There you can adjust the stale threshold that is the multiplier by which the server determines that updates from a driver have become stale. So if your scan class is 1 second you have 2.5 seconds until the tag will become stale if we see no data. You can bump that up to 3 and your overlays will probably go away.
I noticed in another thread you set your “Concurrent Requests” property to 1 on your drivers. This is likely a move in the wrong direction.
I would recommend using at least 2, and maybe more on devices which have a high number of tags subscribed (thousands, perhaps).
Good point. It could be that you are jamming to many requests into one causing stale overlays.
I have my stale threshold set to 20, and my typical sampling rate is 250ms, so that should give me 5 seconds. There is no way I’m getting delays longer than that.
I tried raising the concurrent requests to 2 and it is still happening. I really don’t have that many tags set up (150, most of them BOOL or DINT, and some STRING).
[quote=“alex.ferrell”]I have my stale threshold set to 20, and my typical sampling rate is 250ms, so that should give me 5 seconds. There is no way I’m getting delays longer than that.
I tried raising the concurrent requests to 2 and it is still happening. I really don’t have that many tags set up (150, most of them BOOL or DINT, and some STRING).[/quote]
Pick a device that’s giving you trouble and go to the [diagnostics] link next to it when you’re looking at the device list in the gateway. Can you screenshot that and show us?
Diagnostics
Request Schedule
SubscriptionItem Count 150
ScheduledRequest Count 3
Refresh
Request Cycle
Request Throughput 13.0/sec
Min Request Duration 0.0ms
Max Request Duration 2485.0ms
Avg Request Duration 6.2ms
Last Request Duration 0.0ms
Refresh
@250ms
Request Count 3
Request Throughput 11.7/sec
Min Request Duration 0.0ms
Max Request Duration 2485.0ms
Avg Request Duration 6.2ms
Last Request Duration 0.0ms
Avg Wire Time 6.2ms
Avg Queue Time 0.0ms
Refresh
Well, everything on that device looks OK. I see at one point there was a ~2400ms delay, but that wouldn’t have caused a stale quality with the multiplier at 20.
Maybe you can call into support and let them poke around a bit. Or maybe that particular device just hasn’t seen a delay that causes stale quality yet.
I might have to call in. That is the only device that I have- all my tags point to that device. Is a stale state the only thing that can cause the red overlay?
No, anything other than good quality will cause an overlay of some kind. Maybe we’re looking in the wrong spot. Call in whenever it’s convenient.