"Computer Nerd Kev" wrote in message
. ..
On 21 Feb 2013, Ian Field wrote:

In equipment like a VDU, where there are pulsed currents
above the hearing frequency - electrolytics suffer a lot of
ripple current, the weak ones will get noticeably warm - or
even hot.

Your sense of touch could save you the cost of an ESR meter
- but the aluminium can isn't isolated, so rail decouplers
on negative rails will be live.

I presume I could use an infared temperature sensor to do the
same job while keeping my fingers out of zapping range?


In theory yes - but accuracy is very dependant on the reflectivity of the
surface.

Another trick - any capacitor that can melt a hot glue stick is in serious
trouble!