[En-Nut-Discussion] Power Strip Program

[Nic Cave-Lynch]

Sounds interesting. Look at hall-effect devices for non-invasive (and isolated) 
current monitoring. I used them once measuring load deltas: just tape/epoxy them 
against the power cable ad away you go. Not sure how repeatable they'd be in 
productions quantities. The resultant voltage depends on thickness of insulation 
and device orientation as well as load current. It might be completely practical 
to calibrate them as part of a production testing process.

Nic C-L

Mark J Elkins wrote (among other things):
> 
> The POWER STRIP will have at least twelve sockets with an additional
> Euro Socket at the top for powering the cabinet fans.  The Sockets
> will be those used in South Africa (3 round pins).  The sockets and
> mains voltage could be different for different markets.  Typically,
> there will be a Euro Plug at the bottom of the strip for a connection
> to the UPS.  There will be a "normally closed" relay per machine
> socket.  There will be a Red LED per relay showing that the relay is
> now Open (the "unusual" state).  If any relay is open, the Red LED on
> the front panel display should also come on.  Each Power and Euro
> socket will have a current measuring device to enable the current for
> all devices to be calculated (total input current from the UPS, each
> machine socket and the fan socket).  This could be as simple as a very
> low valued resistor in series with the supply, with a "sensor" wire
> from the load side and a single common wire from the supply side -
> although this would result in high voltages being present in the
> control box.  **** Of everything in this document - this is the only
> area in which I am personally not sure how to proceed.****
>