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Do-more CPUs and Do-more Designer Software / Re: F2-8AD4DA-1 failures Analog Module Cold Start Failures
« Last post by AdchemElectrician on July 08, 2026, 01:46:49 AM »Thank you for your reply I will speak to them.
- July 16, 2026, 05:05:44 PM
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2
Do-more CPUs and Do-more Designer Software / Re: F2-8AD4DA-1 failures Analog Module Cold Start Failures
« Last post by BobO on July 07, 2026, 11:01:47 PM »Hi everyone,
I'm hoping someone has come across this issue before.
I'm running several DL205 H2-DM1E systems with F2-8AD4DA-1 analog input/output modules.
The problem is that after the PLC has been powered down, the analog module often fails to initialise correctly when power is restored. When this happens:
All analog input raw values remain at 0.
The PLC starts normally.
The module is still detected and appears to be present.
The fault affects all analog inputs simultaneously.
The interesting part is:
If I gently warm the analog card with a heat gun for a short time, it starts working normally.
Once it has started, it continues to operate correctly until the next power cycle.
We've also found that changing the startup sequence or occasionally reseating the module can sometimes get it going, but the next cold start usually causes the problem again.
This isn't an isolated case. Over the past 12 months we've had around 10 F2-8AD4DA-1 modules develop the same fault, and we have approximately 60 modules installed across our site. It's becoming a significant reliability issue, so if there is a known repair or common component failure, we'd much rather repair the modules than replace them.
At this stage I'm suspecting an ageing component on the module, such as an electrolytic capacitor, voltage regulator, or another startup-related component, but I haven't started replacing parts yet.
Has anyone experienced this with the F2-8AD4DA-1?
I'm particularly interested in:
Whether this is a known failure mode.
Which components are most commonly responsible.
Whether anyone has successfully repaired one (for example by replacing capacitors).
Whether Host Engineering has identified a common cause.
Any recommended checks or measurements before I start replacing components.
Any advice would be greatly appreciated.
Thanks,
Matt
That's not a Host product, FACTS Engineering makes it.
3
Do-more CPUs and Do-more Designer Software / F2-8AD4DA-1 failures Analog Module Cold Start Failures
« Last post by AdchemElectrician on July 07, 2026, 06:09:03 PM »Hi everyone,
I'm hoping someone has come across this issue before.
I'm running several DL205 H2-DM1E systems with F2-8AD4DA-1 analog input/output modules.
The problem is that after the PLC has been powered down, the analog module often fails to initialise correctly when power is restored. When this happens:
All analog input raw values remain at 0.
The PLC starts normally.
The module is still detected and appears to be present.
The fault affects all analog inputs simultaneously.
The interesting part is:
If I gently warm the analog card with a heat gun for a short time, it starts working normally.
Once it has started, it continues to operate correctly until the next power cycle.
We've also found that changing the startup sequence or occasionally reseating the module can sometimes get it going, but the next cold start usually causes the problem again.
This isn't an isolated case. Over the past 12 months we've had around 10 F2-8AD4DA-1 modules develop the same fault, and we have approximately 60 modules installed across our site. It's becoming a significant reliability issue, so if there is a known repair or common component failure, we'd much rather repair the modules than replace them.
At this stage I'm suspecting an ageing component on the module, such as an electrolytic capacitor, voltage regulator, or another startup-related component, but I haven't started replacing parts yet.
Has anyone experienced this with the F2-8AD4DA-1?
I'm particularly interested in:
Whether this is a known failure mode.
Which components are most commonly responsible.
Whether anyone has successfully repaired one (for example by replacing capacitors).
Whether Host Engineering has identified a common cause.
Any recommended checks or measurements before I start replacing components.
Any advice would be greatly appreciated.
Thanks,
Matt
I'm hoping someone has come across this issue before.
I'm running several DL205 H2-DM1E systems with F2-8AD4DA-1 analog input/output modules.
The problem is that after the PLC has been powered down, the analog module often fails to initialise correctly when power is restored. When this happens:
All analog input raw values remain at 0.
The PLC starts normally.
The module is still detected and appears to be present.
The fault affects all analog inputs simultaneously.
The interesting part is:
If I gently warm the analog card with a heat gun for a short time, it starts working normally.
Once it has started, it continues to operate correctly until the next power cycle.
We've also found that changing the startup sequence or occasionally reseating the module can sometimes get it going, but the next cold start usually causes the problem again.
This isn't an isolated case. Over the past 12 months we've had around 10 F2-8AD4DA-1 modules develop the same fault, and we have approximately 60 modules installed across our site. It's becoming a significant reliability issue, so if there is a known repair or common component failure, we'd much rather repair the modules than replace them.
At this stage I'm suspecting an ageing component on the module, such as an electrolytic capacitor, voltage regulator, or another startup-related component, but I haven't started replacing parts yet.
Has anyone experienced this with the F2-8AD4DA-1?
I'm particularly interested in:
Whether this is a known failure mode.
Which components are most commonly responsible.
Whether anyone has successfully repaired one (for example by replacing capacitors).
Whether Host Engineering has identified a common cause.
Any recommended checks or measurements before I start replacing components.
Any advice would be greatly appreciated.
Thanks,
Matt
4
Do-more CPUs and Do-more Designer Software / Re: BRX dropping out of run
« Last post by BobO on July 07, 2026, 02:00:18 PM »plc rebooted following hardware watchdog timeout
Electrically noisy environment?
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Do-more CPUs and Do-more Designer Software / Re: BRX dropping out of run
« Last post by jwbaker3 on July 07, 2026, 01:43:41 PM »plc rebooted following hardware watchdog timeout
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Do-more CPUs and Do-more Designer Software / Re: BRX dropping out of run
« Last post by BobO on July 07, 2026, 12:40:58 PM »I have a system with 4 Brx plc's and a AB 5069 networked together, the Brx will randomly drop out of run. Cycle the switch and all's good (except restarting the system) could this be due to firmware? Or ? any ideas? we are talking to 5 Fanuc robots and 21 drives and messaging information between the Brx, the AB had one of the Brx setup as remote IO
Thanks,
JW
What does the log say?
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Do-more CPUs and Do-more Designer Software / BRX dropping out of run
« Last post by jwbaker3 on July 07, 2026, 12:38:23 PM »I have a system with 4 Brx plc's and a AB 5069 networked together, the Brx will randomly drop out of run. Cycle the switch and all's good (except restarting the system) could this be due to firmware? Or ? any ideas? we are talking to 5 Fanuc robots and 21 drives and messaging information between the Brx, the AB had one of the Brx setup as remote IO
Thanks,
JW
Thanks,
JW
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Do-more CPUs and Do-more Designer Software / Re: DM2 CPU?
« Last post by Ssweber on June 30, 2026, 11:29:56 AM »I’ve been making a Click plc-compatible Python runtime (I know, competitor, bad grr) and wanted to chime in on the AI angle: ultimately what makes AI most useful is its ability to run whatever code it produces in simulation - preferably scan by scan. AI is only as good as its training, and it does not reason well about the cyclical nature of plcs. Without being able to check its work - its output is not trustworthy.
So input/output of the coding language is important, but simulating it is also crucial. Host/Do-More is in a great position to allow the llm to both write the code and execute it - if you go that route having a scan-by-scan debug hook into the simulator would allow easy introspection - that would put you in a great position.
Hope my drive-by-comment is helpful
So input/output of the coding language is important, but simulating it is also crucial. Host/Do-More is in a great position to allow the llm to both write the code and execute it - if you go that route having a scan-by-scan debug hook into the simulator would allow easy introspection - that would put you in a great position.
Hope my drive-by-comment is helpful
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General Discussion / Re: New features wanted!! Apply here!
« Last post by Controls Guy on June 29, 2026, 03:32:15 PM »I'm in if you are!As I recently referenced on LinkedIn:
https://www.youtube.com/watch?v=4An1BrG2u_4
Awesome video!
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General Discussion / Re: New features wanted!! Apply here!
« Last post by Controls Guy on June 29, 2026, 03:30:19 PM »It also doesn't necessarily imply cascading. Some of the implementations that support it just allow one state to exit via multiple transitions (like Stage). See below. It's kind of orthodox that a single horizontal bus line is used for exclusive while the double is for parallel simultaneous threads. This "exclusive with priority" one is a new one on me.