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Products => Test Equipment => Topic started by: PushUp on June 23, 2022, 11:14:06 am

Title: Checking (unknown) ZenerDiodes, when a ZEN50 or two PowerSupplies are not enough
Post by: PushUp on June 23, 2022, 11:14:06 am

Nothing special and most likely well known, but as I have nearly forgotten this solution, it may help some others in the future, when you have access to an Insulation Tester...

In order to prove my test setups I obviously took Zener Diodes with known and lower breakdown voltages...  ;)


I had to check some unknown Zener Diodes, which couldn't be solved by using my ZEN50 - the left one measuring the breakdown voltage only shows >50V:


(https://i.postimg.cc/X7S1S8Z4/Bildschirmfoto-vom-2022-06-23-11-48-44.png) (https://postimg.cc/Th0Jnnq4)



...also, connecting my two cheap PowerSupplies, which are limited to roughly 60V, was useless:


(https://i.postimg.cc/PqQTYxB8/Bildschirmfoto-vom-2022-06-23-11-49-09.png) (https://postimg.cc/zLvs1JDJ)



Finally, as I had no luck to cope with >60V with the methods from above, the use of an Insulation Tester becomes a very handy and probably easiest solution to do so, due to its self limiting voltage, in order to find out the breakdown voltage of unknown Zener Diodes:


(https://i.postimg.cc/d0YTJh27/Bildschirmfoto-vom-2022-06-23-12-02-33.png) (https://postimg.cc/yDLNPYrB)



Cheers!  :)