I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.
The relay is just a crude protection. A series resistor limits the current but increases the discharge time, and the delay might be long enough to destroy the MCU. The question is more likely to be whether the MCU or the relay is cheaper. I'd suggest to have a simple process in place to measure the voltage with a DMM and discharge the cap with a resistor before using the Transistortester. This is a good advice anyway when repairing a device.
+1 , without protection an ESR meter would not last long in a real repair scene. I have burnt a Russian cute tiny ESR 4 times and last time it became non-repairable. Same to my capacitance meter. Make it able to withstand 600V, even at 50V, I can retire my Bob Parker ESR.
Oh, advices and procedures. My favorite way of breaking things. I'm working on avoiding it, trying to workaround that bug on me
That's how I break DMMs, so I dream to have a good one of those that advices me to not use the incorrect sockets and even blocking them physically. But I don't understand why DMMs can't use some solid state switching for that (added resistance?) [emoji14]
Would a fine way be too complex to implement? Foolproof, absent minded people that forget things quite often
I asked in the German forum about newer hardware project files. It would be nice to do an Open Hardware contest for it. I myself would like to try to do it both in OrCAD and KiCad, if my mind gets in better shape
What would be the better AVR to be supported?
I want to add a relay to the tester to protect it from charged capacitors. Should I include a series resistor to limit the discharge current?
I know that when the "screwdriver method" is used with high energy caps, there is a visible arc, and then damage to the surface of the piece of metal used. Maybe the arcing would eventually destroy the relay contacts, or possibly weld them shut. I think a 1R3 resistor would do the trick.
The relay is just a crude protection. A series resistor limits the current but increases the discharge time, and the delay might be long enough to destroy the MCU. The question is more likely to be whether the MCU or the relay is cheaper. I'd suggest to have a simple process in place to measure the voltage with a DMM and discharge the cap with a resistor before using the Transistortester. This is a good advice anyway when repairing a device.
+1 , without protection an ESR meter would not last long in a real repair scene. I have burnt a Russian cute tiny ESR 4 times and last time it became non-repairable. Same to my capacitance meter. Make it able to withstand 600V, even at 50V, I can retire my Bob Parker ESR.
Oh, advices and procedures. My favorite way of breaking things. I'm working on avoiding it, trying to workaround that bug on me
That's how I break DMMs, so I dream to have a good one of those that advices me to not use the incorrect sockets and even blocking them physically. But I don't understand why DMMs can't use some solid state switching for that (added resistance?) [emoji14]
Would a fine way be too complex to implement? Foolproof, absent minded people that forget things quite often
I asked in the German forum about newer hardware project files. It would be nice to do an Open Hardware contest for it. I myself would like to try to do it both in OrCAD and KiCad, if my mind gets in better shape
What would be the better AVR to be supported?