In article ,
Lionel wrote:

Kibo informs me that Nick Hull stated that:

In article , CJT
wrote:
I'd look closely at your automatic switch. Perhaps it's generating
an RF pulse when it switches state that is somehow reaching your
inverter. The solution might be as simple as a capacitor across the
switch, or a cheap filter between it and the inverter.

My 'automatic switch' is just a DC relay powered from the AC mains with
rectification and a capacitor. If the power fails the cap will hold the
relay in for 10 seconds, then it drops out to energize the CF light. I
don't see any RF pulse there, do you?

Unless you quench it somehow, you'll get a big voltage spike, (resulting
in an RF glitch), any time a coil (such as your relay) is switched off.
Does the coil of the relay have a diode or cap across it to sink the
spike? If not, that may well be the cause of your problem.

The coil isn't 'switched' off, it just slowly decays until it drops out
for lack of current, while current is still flowing but too weak to hold
the relay in.

When switching heavy loads with a relay, it's also good practice to put
an RC supression circuit across the contacts to prevent sparking, which
will generate RF, as well as being bad for the contacts.

Very true, but this is only switching a 7 watt CF bulb.

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/