Data Point value is not updating until refresh or force read button is pressed
I have an issue with power data points using Modbus IP. The value does not change until refresh or force read button is pressed. It is updating every minute interval but only reflecting the previous value so the graph looks like a straight line and excel reports only shows one value for the whole day.
I've played around with the interval but it does not seem to resolve the issue. When using a reader tool directly to the Modbus, we can see it the value is changing. So it must be the software that is causing this. I am running Mango Automation v3.0.
Appreciate your help.
Could you please export your data point settings and post it on the forum.
phildunlap last edited by phildunlap
To me, that sounds like you have more than one point on the Modbus data source and that there is a gap in the registers between the points you intend to read that the device considers an illegal data address. I would have expected you to have events for point read errors on the events page. The solution is likely to check "Contiguous batches only" such that only registers you have configured are read, and not bundled into larger requests to reduce the total number of requests
i.e. points at holding register 0 and 99, max read registers of 100
w/o contiguous batches you'd send one request to read holding registers, at index 0 for 100 registers. If you do not have permission to read register 50, this will fail with an illegal data address error.
w/ contiguous batches you'd send two requests, one for index 0 length 1 (depending on point locator data type I guess, since it could span a couple registers if it's an eight byte type, for instance) and a second request for index 99 length 1.
But, when you force a point read, you only send a request for that one point, and there is not a chance to bundle other registers into the request. The one minute data you describe as being the same is likely the result of the interval logging going about its business without getting updates, due to the error responses from the device.
MattFox last edited by MattFox
Do your datapoints have logging set to All not Interval?
Contiguous batches only
Thank you Philip! The issue was resolved by clicking Contiguous Batches Only on the Data Source settings.
Hi Philip. It did resolved the issue and the value is now updating on my watchlist. However, in my excel report, it still isn't. Weird thing the value updates on my excel report only during 6:00PM to 11:00PM or sometimes later than that. While the AM data is still stuck.
Any idea? I have attached the excel report screen shot.
We will need to see your logging settings for the data points and your excel rollup settings for the report.
Below is my excel roll up, datasource and datapoints logging settings. I have a feeling it is something to do with the discard low limit and high limit?
Data Point logging:
Data Source settings:
Excel roll up settings:
Appreciate the help.
Firstly your data source is set to update at 5-minute intervals. You could reduce this to 5-10 seconds.
your data points are logging the average at 1-minute intervals. There will only be one value to average out. So there will be 5 values that are the same in a 5 min period.
you are then reporting the 1-hour average of these values smoothing them out even further.
I would try the following:
1.change the data source to 5-second poll rate.
2.change data point logging to instant
This works pretty well. Thank you Craig!
phildunlap last edited by
I suspect the reason you had the older, unchanging data prior to 6 PM in the report is that the time period type selected is "Previous" which will be distinct by "Past" by aligning to the previous period boundary (so, midnight for days, changes the end time) before subtracting the period to get the start time.