[time-nuts] the care and feeding of LPRO's

[Magnus Danielson]

On 07/10/11 20:30, John Lofgren wrote:
>
>> fortunately, everything in the "lab"(basement) is on UPSs so in theory
>> the input voltages to the equipment should be pretty constant and I
>> was already planning on using a linear supply.
>
> Be careful, there.  Most consumer type UPSs are not line regulators.  When there is sufficiently
> high line voltage they are completely out of the circuit and the line voltage is passed through to
> the output unaffected.  They're usually not designed for continuous operation of the inverter
> circuit.  There was a more in-depth discussion of this a while back in a thread about running
> 50 / 60 Hz clocks from a locked frequency source.

Indeed. Even large UPSes usually run in bypass mode to save power. 
Actually running the DC to AC conversion isn't used much these days.

It's much more difficult to kill my argument that most modern equipment 
run on switchers, which causes much less variation on power dissapation 
with supply voltage, but I was careful to talk about linear supplies...

Cheers,
Magnus