On 11/12/2008, Mark Rages <markrages@gmail.com> wrote:
>  >
>  > We used a cable measurement system with a similar power suppy
>  > connection. All went well until the sense wire connection broke and
>  > the power supply started delivering 8 volts or so to about 500 TTL
>  > chips.
>  > Cost _a lot_ of money to rebuild but we ended up with a much more
>  > reliable system in the end.
>
>  Every Kelvin-connected power supply I've seen has  resistor or a few
>  hundred ohms between "force" and "sense" to prevent exactly this
>  occurrence.  But I suppose the "sense" wire could become loose and
>  touch ground or something.
>
>  Regards,
>  Mark
>  markrages@gmail
>  --


Yes, the fixed version certainly had such a resistor fitted to the PS
unit  (along with a crowbar ckt on the main test frame) , I'm not sure
if the original did or not,

RP
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