snoofer Last edited by:
snoofer Viewed: 408 times
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Contributed by: Moshmont Submitted: 01-12-2003
Assuming your ballast is hooked up right and
is relatively new, the capacitor (cap) and socket
are about the only things that will give you
problems. They last about 5 - 10 years on avg.
Igniters (ign) on the other hand (if equipped)
last much longer, at about 15 - 20 years. The
transformer (tran) part of the ballast will last
even longer, assuming it does not have
deteriorated leads or mechanical damage.
All life expectancies are shortened buy
about 30%, if the ambient temp surrounding the
ballast is much higher than 110C (230F). All the
more reason to give your ballast good venting.
(This doesnt apply to the socket obviously)
Besides the changing of bulbs every 8 to
12 months, you need to check out following:
Checking the ballast
Polarization (ballast) Make
sure the white / black wires are where they are
supposed be. Black wire to LOAD / White wire to
COM< power source If reversed, the ign (if
equipped) may not work and the cap might wear out
faster than it\'s supposed too, same thing for the
Polarization (socket) The
black lead should go to the tab in the center of
the socket and the white lead to the threaded
metal. If reversed the bulb may not work or wear
out faster than it\'s supposed to.
Leads (cap, ign, tran and socket) Make sure they are not loose or deteriorated.
Give them a little pull as well as bend them (in
the middle) at an 180 degree angel. If they feel
like they are about to come loose or show cracks
in the insulation, replace the component. If the
lead is cracked (pic#1), shrink wrap the lead as a
temporary fix till you can get a new component.
Check that the socket is not cracked and make sure
the fiberglass insulation is not torn up or
unraveled (pic#2). If the tab looks burnt up or
discolored (pic#3) replace the whole socket.
(Another thing about the socket. You know
those little cardboard-like washers you get with
the mogul and some medium sockets...? They are
there for slack so when the socket heats up and
expands, the rim of the screw holes dont chip off.
That way you can mount it nice and secure without
Cap's with leads If
the wires are off center, one wire is closer to
the rim of the top of the cap. The wire closest to
the rim of the cap should go to the long side of
the transformer and the wire farthest from the rim
should go to the short side. If the wires are not
off center than any way is fine. I\'m sure it will
run fine ehter way, but the cap may wear out
Note: If at any point you notice
the cap looks bulged-out, replace it ASAP.
Testing the capacitor (cap)
Things you will need: A screw driver and
Step one: Disconnect
the cap from the transformer and discharge it
If your light was just running, wait 10 or
15 minutes. Disconnect it, then touch the leads to
the metal part of the cap 2\" apart. If it does
not have a metal case do so on a peace of bear
metal. If you have the kind that looks like a 9V
battery touch both terminals (at the same time) to
a screw driver or a piece of bare metal.
Step two: Find out the UF of the cap
It should be printed somewhere
Step three: Set the ohms /
multiple tester to the F or UF function for
Touch one probe to each
terminal / lead and note the number. It should be
with in 10% of what is printed on the cap.
Note: You have to keep the probes on it
for a little while to get a reading.
get percent you take the number, times point the
percent you wish to know Exp: 100 x .10 = 10 (this
is your ten percent of the number.)The percent
added or subtracted from the number = the number
at + / - the percent. If it is over / under 10% of
what printed on the cap failure is soon to follow.
If you get an OL (infinity) or close to 0
reading; reverse the + / - probes and try again.
If you get the same thing your cap has crapped
If you suspect the ign, get a new one
and try it out (you can always return it if its
doesnt look like its been used). HID capacitors
and igniters can usually be bought at retail
electrical supply stores for around $5 to $15 each
A note about buzzy ballasts:
The sound is probably the transformer
plates shaking apart. The outer parts of them are
only held together with that coating, over time
the lacquer coating breaks apart and the plates
get loose. When the transformer heats up, that
stuff gets soft and the plates can move around
Solution: >get a new
transformer >What I have done before is
drill out the holes in the transformer and run
some small bolts though it. That usually quiets
Last modified: 13:58 - May 29,
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