Hello,
I have accidentally applied 230VAC to a 24VAC valve (an external fuse was blown). The valve has a control board and it can be controlld via 4...20mA and gives feedback as well. There are 2 PCB connected with wires as you can see in the images added.
I opened it up and I can only find one burnt element on it, which for me seems to be a transient voltage suppressor. It now measures short, but the traces around it are connected. The writing on the element is "AUTO K30 1741" - I could not find a part like this online.
When now applying 24VAC to the valve it does nothing and is not short circuited, which confuses me, since as of my understanding the shorted suppressor should be in the supply line. One side of the suppressor is connected to the supply and the other goes to the control board, I did not have time to study further. I could not find a fuse on the board and as I said - no visible damage to other elements or traces.
I would appreciate any advice for fixing it or atleast helping me understand what has happened. Is it safe just to desolder the suppressor and apply voltage again? Am I missing a fuse on the board?
I have accidentally applied 230VAC to a 24VAC valve (an external fuse was blown). The valve has a control board and it can be controlld via 4...20mA and gives feedback as well. There are 2 PCB connected with wires as you can see in the images added.
I opened it up and I can only find one burnt element on it, which for me seems to be a transient voltage suppressor. It now measures short, but the traces around it are connected. The writing on the element is "AUTO K30 1741" - I could not find a part like this online.
When now applying 24VAC to the valve it does nothing and is not short circuited, which confuses me, since as of my understanding the shorted suppressor should be in the supply line. One side of the suppressor is connected to the supply and the other goes to the control board, I did not have time to study further. I could not find a fuse on the board and as I said - no visible damage to other elements or traces.
I would appreciate any advice for fixing it or atleast helping me understand what has happened. Is it safe just to desolder the suppressor and apply voltage again? Am I missing a fuse on the board?
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