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Re: The Urge to Surge & Compact Flourescent Bulb & Ballast Life



JoAnn VanDersarl said, in part, about her failing JBJ
ballasts:

> The fixture with the ballast failure is a 2x96 watt with
> fans. I'm 
> just more or less fit to be tied here. The bulbs in the
> other 
> fixture, a 4x65 with fans, have also gone out. All are
> connected 
> through surge protectors, so I doubt a spike got to them.

I doubt it, too, although appliance manufactures like to
blame surges and spikes for electrical component failures.

The surge protectors need to be good ones; those ones that
cost barely more than a power strip can do barely more. 
Also, the cheaper ones, and many of the more expensive
ones, rely on MOVs (Metal Oxide Varistors) to provide
protection from spikes.  These solid state devices wear out
from receiving strong spikes -- they are, in essence,
slowly-sacrificial soldiers.  If your house circuit is
getting a lot of very strong spikes, then you need to
replace the MOVs (or the surge protector itself) every so
often.

Some surge protectors that don't rely on MOVs (like Belkins
Surgemaster IIs) rely on Sidactors, which are a little more
durable but are still essentially sacrificial components. 
Other surge protectors rely on entirely different circuit
topologies without sacrificial components but tend to cost
a few hundred dollars --ouch, isn't it cheaper to lose the
ballast? hmmmm

And there can be noise on the house circuit that no
off-the-shelf surge protector or line conditioner is going
to stop.  Your surge protector might have come in a box
that said it will stop spikes of 500 joules, but if the
transient signal isn't within the frequency range of the
filters, the surge protector will jsut ignore it like a
blind guard.  I had a 13 watt mag-ballasted lamp (no, not
the AH Supply kit) that gave out a switching (on/off)
transient that went through every thing I put in it's way. 
Rather than try to design a custom filter, I replaced the
lamp with one with an electronic ballast ($25 incl. bulb). 
The electronic ballast would put more continuous high
frequency noise on the house circuit, but that stuff is
easily filtered by moderately priced filters.  But it won't
drop the big voltage spike that some mag ballasts put out. 
BTW, this kind of fluorescent-lamp switching transient is
the kind of thing that in some cases trips GFCIs when, you
turn them off.  The transient is caused by the ballast and
the arcing that occurs across the switch contacts when you
turn off the switch.  Usually a new switch or a different
ballast will help the problem.

And while we're on the subject, don't expect any surge
protector to protect you or your equipment from a lightning
hit -- that's like using a baseball bat to stop a train.  

Scott H. 

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