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electronic ballasts, Grainger, etc.
Sorry. My email program is totally intermittent, which is making any UN -
disjointed replies impossible. Thus, this reply may well not take into
account a few days' worth of posts to the List. (If you wonder, it is AOL
3.0 which is totally unreliable on email, while 2.7 works perfectly all the
time! :-[ )
The Instant Start ballasts I listed in an earlier post are OK for 48 inch, 36
inch, and (Not entirely sure of this one! :-[ ) probably either 24 inch or
30 inch "new style" high efficiency T-8 bulbs. The ballast lists the WATTAGE,
but not the length of the bulbs it is designed for. The Electronic ballasts
do NOT use the filaments on the ends of the bulbs, but use an electronic
"kick in the pants" to start the arc. I would guess that they may initiate
ionization of the tube with high frequency AC, but although the concept is
logical, I have no evidence to support that idea.
Rapid Start Bulbs (and the bulbs that require a manual start switch or a
"starter circuit") have filaments at each end of the bulb. The start the
bulb, the filaments are heated, which "boils off" a cloud of electrons which
fill the tube, thereby providing a "path" for the arc. In Rapid Start Bulbs,
the ballast puts a small, continuous current through the filaments as long as
the bulb is "on." In the "ordinary," or "Pre-Heat" bulbs, the starter
(either the manual push button switch which you hold down for a few seconds,
or the "starter circuit," which does the same thing electronically) puts a
much stronger current through the filaments until the arc is started, then
the current THROUGH the filaments is stopped. This explains why the Pre-Heat
bulbs won't work on ordinary Rapid Start type magnetic ballasts. The
magnetic ballasts don't put enough current through the filaments to make the
arc start. Oddly enough, you can often HAND START the arc by rubbing the
bulbs with your hands, from one end to the other. Your hands are "grounded"
by your body, which is poorly grounded through your feet and your shoes. (If
you are barefoot, your hands are very well grounded!) In any event, the
"capacitance" effect of your hands rubbing on the outside of the bulb often
"induces" the cloud of electrons on the inside of the bulb to follow the
movement of your hands, thus starting the bulb. Sounds goofy, but it works.
Most of the time, at least. You can often improve your chances of getting a
Pre-Heat bulb to work with a Rapid Start ballast by having ONE bulb of the
pair a normal Rapid Start bulb.
You will have to ask the Electronic Engineers who design the bulbs why they
do things this way - I haven't a clue. Since "Rapid Start" bulbs work just
fine with "Pre-Heat" ballasts, why don't they make ALL the bulbs "Rapid
start?" I have no idea, but perhaps someone on the list can answer that
GRAINGER is a "Wholesale FROM Business TO Business" contractor or business
supply company. They have branches over practically the entire US. I checked
in the front of the latest catalog, and they have LOTS of branches in
California. Just look in the Yellow Pages, or under Business phones, under
GRAINGER. They are pretty fussy about only selling to _Businesses,_ but
that is ONLY to keep from being hassled by retailers, and by Retail customers
who don't know what they want. You normally come in, and there is a display
area and an order counter, with several POS computer registers. You can look
in the catalog, then you give the person behind the counter the catalog
number of the "whatever" you want, and they look in the computer to see if
they have it. If not, they will see if any OTHER branch in your state has
the desired item. They DO COLLECT SALES TAX, and WILL charge you it unless
you have an exemption certificate on file and sign that the stuff you are
getting is "for resale," meaning YOU are responsible for collecting the tax.
Here in Iowa, all businesses MUST PAY sales tax on any item used up in the
You can set up your own "Business" and set up your own account with them.
They normally "charge" everything, then send you an invoice. Very nice way
to get things, once you get "on the list" of approved customers.
They carry stuff varying from toilet paper (no kidding!! 8^D ) to concrete
finishing tools to electronic stuff to hand and machine tools. The current
Grainger catalog is about four inches thick, which tells you why it is NOT a
HOWEVER - - - - If you have a business CONNECTION, you can get the stuff
anyway. You tell them what you want, and who you are getting the stuff for,
and they check you out in the Computer, and if the Business exists, they will
get you whatever you want. They really are nice people! The problem is, YOU
HAVE TO KNOW WHAT YOU WANT, as the catalog is over 3,500 pages thick, and the
illustrations and descriptions of things are NOT geared to the ordinary
person, but to Contractors and business folks who know what they want. If
they have your stuff, they disappear back into the warehouse, and bring it
out to the counter. It is up to you to get it loaded into your car, etc.
One more thing - If you are going to use the new T-8 High Efficiency Bulbs,
you need to get a ballast DESIGNED FOR THEM. As I said in an earlier post,
Rapid Start Bulbs - if of the proper wattage - WILL work OK with Electronic
Ballasts. The "match" is not "correct," but my Electronic Engineer friend
says it is not critical. Bulb life may be shortened, but most of us replace
our bulbs LONG before they are "worn out," and my friend says the difference
in life is not very large. But, if you can get the "right" bulbs, at the
"right price," why not do it?
I hope this will be helpful.