All,
Large value electrolytics have significant self inductances ie. impedance to
high frequencies. The Rotax regulator is a switching device which shorts
half cycles to ground every now and again (on low load) and produces high
frequency, high voltage spikes in so doing. (This is the cause of most RF
interference). This combination can easily exceed even the 25v value for
very short periods. Whatever, a 16 volt cap. blows up nicely after a very
short time - and very spectacular too. Been there.
Dave Simpson
-----Original Message-----
From: Fred Fillinger <fillinger@ameritech.net>
Date: 11 January 2000 04:47
Subject: Re: Re: 22,000uF capacitor
>Robert L. Nuckolls, III wrote (in part):
>
>> Capacitors rated for operation at 85 degrees C are standard.
>> Further, they don't have to be big either. A 33,000 uFd,
>> 16 volt device can be had with an envelope of 1.4" diameter
>> and 2.13" long.
>
>16 volt? Ouch!. Maybe a typo. Both Rotax and
>Europa recommend 22,000-25v. 16v. is just too
>close to the regulated output.
>
>Regards,
>Fred Filinger, A063
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