Work for you Chris?ChrisAttebery wrote: ↑Sat Feb 06, 2021 11:14 am That’s great news. I added a 1mf tantalum cap to my analog output too.
VFD Voltage/RPM fluctuating
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Re: VFD Voltage/RPM fluctuating
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
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We can't "SEE" what you see...
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Re: VFD Voltage/RPM fluctuating
It helped. I still see .1-.2 Hz fluctuations on my VFD. It isn’t noticeable like it was before though. The machine plows right through aluminum.
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Re: VFD Voltage/RPM fluctuating
Did you add a .1mf or a 1mf cap?ChrisAttebery wrote: ↑Sat Feb 06, 2021 11:14 am That’s great news. I added a 1mf tantalum cap to my analog output too.
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Re: VFD Voltage/RPM fluctuating
A 1 micro Farad cap.
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Re: VFD Voltage/RPM fluctuating
Adding too much capacitance to opamp outputs can also cause stability problems. I would try 0.1uF or less. A low value resistor (10 to 50 ohm) in series between ACORN and the capacitor can also prevent oscillation from too much capacitance.
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Re: VFD Voltage/RPM fluctuating
I'll have to see if I have anything smaller. Most of the electronics components I have are from projects 20+ years ago.
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Re: VFD Voltage/RPM fluctuating
Matt,
Could you draw a simple sketch of what you are describing and how it connects to Acorn's analog output for clarity's sake please?
In what cases might this help?
Thanks
Marty
Reminder, for support please follow this post: viewtopic.php?f=20&t=383
We can't "SEE" what you see...
Mesa, AZ
We can't "SEE" what you see...
Mesa, AZ
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Re: VFD Voltage/RPM fluctuating
I'll give it a try, I have a few .1 uF tantalum caps laying around. #104 I think they are. My machine is pretty solid but I may even try one on mine to see if it makes a difference or not.
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Re: VFD Voltage/RPM fluctuating
I checked my VFD tonight. It was rock solid with a 1 micro farad cap.