ok so i have this pc motherboard turn it on the fan spins for about 6 seconds the n cuts out so i was messing about seen a few swelled caps took them out replaced them but still have the same problem so i started checking the inductors by taking them out the last one i took out it had 6 coil turns on it after i took it out the board stays going with out shorting out now im thinking is the inductor or something on the trace of it why would it short out i know these store energy in magnetic field but cant picture whats going on
I would imagine it's VERY unlikley to be the inductor at fault, far more likely there's a short on the board somewhere, and disconnecting the inductor is isolating it.
I would presume that the duff capacitors have blown something?.
thats what i thought also that very unlikely the inductor there is 6 capacitors in series that are after the inductor they are slightly sweld maybe best replace them also one question i have does the capacitor have to be sweld to be faulty
thanks nigel would what would be a good one to go for i bought an oscilloscope but i think was moving to fast not ready for it yet its a hantek dso 1060 60 mhz so maybe a good esr meter would be beter for me can they also be used on smd components
thanks nigel would what would be a good one to go for i bought an oscilloscope but i think was moving to fast not ready for it yet its a hantek dso 1060 60 mhz so maybe a good esr meter would be beter for me can they also be used on smd components
i will go with the one you have i also still havent found the short in this mother board stays on for about 6 seconds then goes out have check a good few caps have checked the voltage on mosfets seems to be good and also you were correct about the inductor i replaced it just to see but same result its isolating the short there is some smd components on the board thats what makes me feel like giving up lol
Electrolytics failing often cause far more damage to other components, as they normally fail as they are used in switch-miode supplies, a common result is the voltage increases until it kills sensitive chips.
thanks for your tips the im running out of ideas as in what components to check there is still about 10 caps that have not been checked i hope it is one of them there is a few chips on the board i will take a picture later and show you the board
thanks for your tips the im running out of ideas as in what components to check there is still about 10 caps that have not been checked i hope it is one of them there is a few chips on the board i will take a picture later and show you the board
You don't need a chart, duff capacitors are always dead obvious, reading FAR higher than a good one should. Just check the reading of new capacitors for a comparison, or check the manufacturers datasheets.
thanks nigel so the capacitance that the peak reads if its real high with no esr is what im looking for how do you find yours for reading in circut i got the latest one just wondering is it accurate in circuit
If you get zero it is, but it's more likely a shorted component somewhere. Good capacitors should give a low ESR and the correct capacitance reading (within tolerance).