testing power transformer

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Hi to u all,
i want to know about the safest means to test the fuse in the primary windings of a power transformer.by that i mean to blow the fuse by a short circuit and see if it is effective to protect the transformer in case of trouble.the winding impedance measured with a digital meter is approx 72ohms for the primary and 5.6 ohms for the secondary.input and output voltages are220 volts and 19.6volts respectively.please note that i am scared to short 220 volts with a screwdriver even when using protecting gloves so i am eager to hear from you experienced diyers on how to handle that matter.thanks.
 
Don't short anything. It is good to be scared. It is not something you would do with a live circuit unless you were suicidal. There is no need to test the fuse as you suggest. The value can be calculated depending on the transformer specs and the circuit it is powering.
 
The only fuse blowing test I have seen was a training exercise for engineering students.
Running the fuse a little above its rating and with a stop-watch time it until it blows. Then repeat at a slightly higher current a few more times increasing the current each time.
Then plot a graph and wait for the tutor to mark your work.
 
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Hi Scott,
i want to know about the safest means to test the fuse in the primary windings of a power transformer.by that i mean to blow the fuse by a short circuit and see if it is effective to protect the transformer in case of trouble.
I'm still pretty sure he was talking about the thermal buried in the windings.

Hi Refugee1,
The only fuse blowing test I have seen was a training exercise for engineering students.
A test that should be at least demonstrated for all electronics / electrical students in every starting course! I did that test myself one day when I was bored. Didn't get caught because explaining what I was doing would probably not be believed.

-Chris
 
at school we were sticking nails into the wall sockets and let a third one drop onto the two between phase and neutral...
I'm still pretty sure he was talking about the thermal buried in the windings.
blowing that fuse would kill the transformer. However even with a non buried fuse testing ones safety concept means risking the transformer by forcing it into overload and short.
Nothing I would do for a DIY-project
 
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