Hi guys,

I've been going to ask for a while about possible causes for the failure of 
some 10,000uF 35v electros that are used in a basic power supply for a 
pulsation controller.

There are 7 of them in parallel and on a couple of occasions I have seen 
where nearly all have swollen and split their tops and leaked and dried out. 
In fact they rattle quite noticeably when you shake them.

>From my understanding I thought that electros only burst if they are fed 
with AC or if their voltage rating is exceeded.

In both cases the rectifiers were ok and on fitting new caps the supplies 
worked fine.

The originals are rated at 35 volts and even unloaded have a maximum of 15 
volts applied. The 240v input would have to more than double to get the 
secondries anywhere near 35v !!!

The originals were also only rated at 85 degrees, and I've fitted 105 degree 
replacements, but while excessive temperature can dry them out, I wouldn't 
have thought it would cause this problem.

I've uploaded an image at    http://imagebin.ca/view/HX_1Ati.html

Any thoughts please.

Regards,   Roger 

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