EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: GeoSaffer on February 27, 2022, 08:59:38 am
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I have had these I2C solder stations for a few months now and they both and they both died on me at the same time.
I looked at the back and saw the fuse box pulled it out and for sure the fuse is blown. I replaced the fused with the supplied extra fuse made sure that the switch is off and then plugged the power cord in. at that moment the solder station turned on for a split second and off again. Thought that was weird but ok let's turn it on,.....and nothing, pulled the fuse out and it was blown again.
OK.....So now we have a short for sure. Tracked down shorted component and pulled it off the board, under it on the PCB is a diode marking. On the component, is a marking "CP".
So this diode runs from 24v pin to 0v pin on the 24v ac line coming from the toroidal transformer. I have no idea what to replace it with.
Any suggestions would be much appreciated.
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might be TVS
Try test by e.g. a circuit like the following
first low Vaa then gradually adjust Vaa voltage via the power supply. Use a universal meter or DMM 29 to test the voltage across D1, as shown. When the D1 voltage stops following the increase in Vaa voltage, this voltage should be your TVS breakdown voltage.
(https://aws1.discourse-cdn.com/digikey/original/2X/9/97ce818837a8ac9d49d7dd40478908d4dde8db62.JPG)