tblough wrote: ↑Wed Jul 10, 2024 7:09 am
What does continuity mean? COM and earth are supposed to be connected and have very low resistance (<1ohm). With the power off and V1 disconnected, COM and V1 will show a high resistance (>1K ohm).
If you have low resistance (<1 ohm) between your disconnected V1 wire and COM you have a short in your wiring. If you have low resistance between COM and the V1 terminal when no wire is connected then you have a bad power supply.
What is the voltage between COM and V1 with the wire disconnected and the PSU powered?
Continuity is the presence of a complete path for current flow
Mattwo said... on the bench continuity between v1 and com yes.. if com is connected to Earth then continuity between v1 and earth is also yes.
To my limited knowledge.. v1 and earth should not have continuity
I most likely have a bad psu..
I will also check what the voltage is between COM and V1 with the wire disconnected and the PSU powered
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I would also like to add that on acorn and acorn six the com and ground on the board is connected by a ferrite. My acorn measures about .2ohm between them. Even if you don't have the jumper between the com and earth of the PSU, we highly recommended that you do, your meter will beep.
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Mattwo_support wrote: ↑Wed Jul 10, 2024 9:49 am
I would also like to add that on acorn and acorn six the com and ground on the board is connected by a ferrite. My acorn measures about .2ohm between them. Even if you don't have the jumper between the com and earth of the PSU, we highly recommended that you do, your meter will beep.
My PSU was wired by you guys and you are the experts so it stay wired as you have done it.
New question.. am I wrong by saying ..
Continuity between V1 and Earth is a short ?
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With the power supply plugged in, and nothing connected, what is the VOLTAGE between V1 and COM? You are measuring the internal resistance of the complex circuit of resistors, capacitors, inductors, and semiconductors, which tells you nothing unless you know what measurement should be, or have another known good one to compare to.
Cheers,
Tom
Confidence is the feeling you have before you fully understand the situation.
I have CDO. It's like OCD, but the letters are where they should be.
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tblough wrote: ↑Sat Jul 13, 2024 5:55 pm
With the power supply plugged in, and nothing connected, what is the VOLTAGE between V1 and COM? You are measuring the internal resistance of the complex circuit of resistors, capacitors, inductors, and semiconductors, which tells you nothing unless you know what measurement should be, or have another known good one to compare to.
Scroll up ....
I wrote.. the voltage between COM and V1 with wires disconnected and power on is 5.089v .. I just didn't take pic
You also asked about the resistance between com and v1 with all disconnected and power off to determine if I had a bad psu.
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