# TimeSeriesChart mid-timestamp tranzitions, and with AsStored shows last value 0 since connection is lost

**URL:** <https://forum.inductiveautomation.com/t/timeserieschart-mid-timestamp-tranzitions-and-with-asstored-shows-last-value-0-since-connection-is-lost/106616>\
**Category:** Ignition\
**Tags:** perspective, ignition81\
**Created:** [May 23, 2025, 7:58am UTC](https://forum.inductiveautomation.com/t/timeserieschart-mid-timestamp-tranzitions-and-with-asstored-shows-last-value-0-since-connection-is-lost/106616 "2025-05-23T07:58:59Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Ervin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ervin/32/57644_2.png) [@Ervin](https://forum.inductiveautomation.com/u/Ervin)\
**Post date:** [May 23, 2025, 7:58am UTC](https://forum.inductiveautomation.com/t/timeserieschart-mid-timestamp-tranzitions-and-with-asstored-shows-last-value-0-since-connection-is-lost/106616/1 "2025-05-23T07:58:59Z")

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I have a TimeSeriesChart history graph that I use as popup for all history enabled values.

My data is via OPC-UA  
My problem is, when I am view-ing a history for a tag thats network connection has been lost  
The chart shows current value 0 for hours since last valid read value and is very baffling.

I must use Quyery mode AsStored, because I found no other way to draw a horizontal line on the graph till next valuechange  
If I check the dataset binding of it, I see that on easch check the last value is 0 with the curreent timestamp. and that is what ruins my graph.

If I set Query mode to periodic, the main problem is that between two datapoints the chart draws a sloped line and does not reflect that the value did not change between two points. especially for tags where value changes are not that often

see a detailed screen capture and ask details if necessary

 ![History Current value 0 when OPC-UA connection lost](https://us1.discourse-cdn.com/inductiveautomation/original/3X/0/b/0b5677dc71324167c1d7443d18d5fae2241fa2da.jpeg)

UPDATE:  
And another big issiue I have with this chart whatever I try. (and probably this is the reason for the problem above)  
Let's imagine the following scenario  
at timpestamp 13h:20m:00s I have a value of 10 and 13h:20m:12s I have a value of 5  
If I choose Query mode "AsStored" the chart shows 10 from 13h:20m:00s to 13h:20m:06s and 5 from 13h:20m:06s to 13h:20m:12s  
If I choose Query mode "Periodic" whatever period even 1second I choose, the chart shows a line as a downslope from 13h:20m:00s to 13h:20m:12s.  
The aggregate configured at the key seems to have no difference if I set it to LastValue os MinMax or whatever valid value I set. (Invalid values result in error).

Ignition v8.1.45

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<div class="post-metadata">

**Author:** ![Ervin](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/ervin/32/57644_2.png) [@Ervin](https://forum.inductiveautomation.com/u/Ervin)\
**Post date:** [May 23, 2025, 10:27am UTC](https://forum.inductiveautomation.com/t/timeserieschart-mid-timestamp-tranzitions-and-with-asstored-shows-last-value-0-since-connection-is-lost/106616/2 "2025-05-23T10:27:10Z")

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UPDATE:  
Prevent interpolation has no effect in AsStored mode. but in as stored mode I have an order of 10-30x less data as if I choose periodic, because I save history on change and ocasionally I have changes each 2-3-10 secnd, and ocasionally only at minutes or hours, depending on field scenarios. so it's only more resource hungry if I let it work with periodic mode and set it to catch sub 10sec. variations.