[time-nuts] Thunderbolt power supply open heart surgery

[Neville Michie]

Hi Jim,
you may have a problem similar to mine.
In Sydney, with a nominal supply voltage of 240 Volts,
the supply at my place is above 250 volts. The supply authority
says that is in the limits of their specification.
I do not know why they run it so high, maybe they think they will  
sell more power.
The problem is that many appliances have a 240 or 250 maximum, dual  
power supplies for 110 V
switch to take 220 V.
My solution is to run my lab through a step down transformer to about  
210 volts.
It puts less pressure on the capacitors in the power supplies.
I have not had a power supply problem for about 4 years now.
cheers,
Neville Michie



On 17/02/2009, at 9:13 PM, Jim Palfreyman wrote:

> Hi folks,
>
> Well I woke up the other morning at 2am to find all the power off  
> in the
> house. I was about to ring the power company and thought I'd better  
> check my
> meter box. Turns out one of the RCDs had tripped. I reset it and  
> all was
> fine.
>
> What puzzled me was what tripped it. It took out my workshop, speaking
> clock, various GPSDOs and an HP rubidium I've borrowed. However all  
> was
> working upon reset.
>
> Today I downloaded Lady Heather and went to test it and noticed the
> should-be-running Thunderbolt was cold. I checked the voltages from  
> the
> power supply and - nothing. Ignoring the life-or-death dire  
> warnings on the
> power supply case I opened it. It had *that* smell. You know the  
> smell of
> that special smoke that keeps all electronic components working  
> because when
> it's released they stop.
>
> R1 is black and charred.
>
> Can anyone tell me what value R1 is and/or where I might get a new  
> power
> supply (just in case it took other components with it)?
>
> Has anyone else had this problem?
>
> Regards,
>
> Jim
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/ 
> time-nuts
> and follow the instructions there.