# About TransientArtificialSource
**URL:** https://forum.spis.org/t/about-transientartificialsource/1424
**Category:** SPIS
**Created:** [26 October 2024 13:52 UTC](https://forum.spis.org/t/about-transientartificialsource/1424 "2024-10-26T13:52:45Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@23131213962](https://forum.spis.org/u/23131213962)
#### Post date: [26 October 2024 13:52 UTC](https://forum.spis.org/t/about-transientartificialsource/1424/1 "2024-10-26T13:52:45Z")
I’m trying a transition class of artificial source, however when I set it up and get it running, the SPIS logs give me the following error:
Error: SourceFluxUpdater not possible to generate for Source3 because the sampler is not of type class spis.Util.Sampler.LocalSurfSampler at spis.Top.Transition.SourceFluxUpdater.updateSimulation(SourceFluxUpdater.java:1
I don’t know how the Sampler class is to be set up and I’m having trouble finding information in the user manual to help me with this.
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### Author:  [@stepan.stverak](https://forum.spis.org/u/stepan.stverak)
#### Post date: [9 March 2026 12:10 UTC](https://forum.spis.org/t/about-transientartificialsource/1424/2 "2026-03-09T12:10:24Z")
Hi, were you able to solve this error? I’m now facing the same problem with SPIS6.2.6 when trying to implement an electron surface source. The source work itself but when I try to set the transient behavior, I get the same error message. Thanks.
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### Author:  [@frejon](https://forum.spis.org/u/frejon)
#### Post date: [8 April 2026 14:41 UTC](https://forum.spis.org/t/about-transientartificialsource/1424/3 "2026-04-08T14:41:27Z")
Hi all. have a look at [Source Pulsing via Transitions](https://forum.spis.org/t/source-pulsing-via-transitions/1566) , perhaps this resolves your issues