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StandardsGuy
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Can I Light Only One F40 Fluorescent Tube?

06/16/2012 12:08 AM

I have a fixture that holds two 4' F40 fluorescent tubes. Is there a way to wire the fixture to light up only one tube? I want to put it in a closet and light up one light. I did this a few years ago in a fixture that had separate starters, but this is a rapid start fixture. There aren't any starters unless they are inside the ballast. The ballast has two blue wires and two red wires one one end, two yellow wires on the other end, and a black and a white wire as the 120V input power.

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SolarEagle
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#1

Re: Can I Light Only One F40 fluorescent Tube?

06/16/2012 1:20 AM

You can wire two into one, overdriving the one bulb....won't work for magnetic balasts only electronic....

http://reocities.com/heartland/pines/7557/overdrv1.html

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StandardsGuy
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#4
In reply to #1

Re: Can I Light Only One F40 fluorescent Tube?

06/16/2012 3:36 PM

Thanks SE, but it's a GE 8G1022W (magnetic I assume).

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lyn
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#2

Re: Can I Light Only One F40 fluorescent Tube?

06/16/2012 9:41 AM

Or, if SE's way is too much work, just paint one bulb flat black.
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StandardsGuy
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#5
In reply to #2

Re: Can I Light Only One F40 fluorescent Tube?

06/16/2012 3:37 PM

Ha Ha

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#3

Re: Can I Light Only One F40 Fluorescent Tube?

06/16/2012 10:43 AM

One will usually light if the other is burned out.

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StandardsGuy
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#6
In reply to #3

Re: Can I Light Only One F40 Fluorescent Tube?

06/16/2012 3:45 PM

Not the case in this fixture. I'm willing to entertain the idea of putting in another ballast if I can get it cheap. One bulb was installed 21 Oct 2008, and the other was installed 14 Apr 2009. This fixture gets very intermittent use, so the lifetime is way too short. All I can blame is the ballast.

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#7
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Re: Can I Light Only One F40 Fluorescent Tube?

06/16/2012 5:24 PM

http://www.amazon.com/72110-GE140RS120-DIY-ProLine-Electronic-Ballast/dp/B001OO9J58/ref=pd_cp_hi_2

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#8

Re: Can I Light Only One F40 Fluorescent Tube?

06/16/2012 10:53 PM

There are dummy bulbs you can buy that simulate the load of a tube and allow the fixture to run. They are a power saving measure.

I see them in offices to lower power use. Hardware stores that sell bulbs also sell these - or can get them

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dkwarner
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#9

Re: Can I Light Only One F40 Fluorescent Tube?

06/17/2012 1:13 AM

For about the cost of a new ballast, you can get an LED lamp and socket. It won't heat the closet as much, and should last your lifetime, with intermittent use.

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StandardsGuy
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#11
In reply to #9

Re: Can I Light Only One F40 Fluorescent Tube?

06/17/2012 11:54 AM

That is correct, see #6. You probably have a newer fixture that is electronic. At work we have fixtures with 4 tubes, and some of them have only 3 lighting. I will look into the "dummy" bulb. I have not seen any LED bulbs sold locally yet. I have a CFL bulb in there now, but I have not been impressed with their lifetimes. I just had a 100W equivalent that died after about 2 months in my living room. I have to set up a stepladder on the stairs to change it, so I am not happy.

Sorry, this was in reply to #10.

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Nothing is Impossible
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#10

Re: Can I Light Only One F40 Fluorescent Tube?

06/17/2012 4:53 AM

are you saying that removing one tube causes the other not to run ?

or if you remove one tube are you concerned that the ballast will overheat or supply too much juice to it ?

i do it in my office where the flouro's are too bright , i just rotate one tube a quarter turn to break the contact and the other works fine
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Wal
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#12

Re: Can I Light Only One F40 Fluorescent Tube?

06/17/2012 11:45 PM

If it is going to be in closet then I imagine it isn't being used much.

How about just using it as is and enjoying the superior illumination for the short duration it is required for?

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StandardsGuy
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#14
In reply to #12

Re: Can I Light Only One F40 Fluorescent Tube?

06/18/2012 8:17 PM

It no longer lights up reliably. On tube has worked 3.5 years, the other 3 years (a few minutes a day). The room is now my electronics lab. The closet has parts in bins and boxes. A light is almost essential. It also gives great non-glaring side light to my computer desk (no doors on the closet).

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Wal
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#15
In reply to #14

Re: Can I Light Only One F40 Fluorescent Tube?

06/20/2012 8:19 AM

Have you tried Solar eagle's fix yet?

I hate twin lamp fittings where the operation of one is dependent on the other's good health.

In these parts a new F40 lamp fitting complete with a tube can be purchased for under USD10.

Replacement ballasts are around USD1.

F40 is a bit long for a closet isn't it?

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StandardsGuy
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#16
In reply to #15

Re: Can I Light Only One F40 Fluorescent Tube?

06/21/2012 12:10 AM

SE's post #1 won't work on my ballast.

F40 is a bit long for a closet isn't it?

No, not at all. I like the even light, but 80 watts is more than I want.

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dkwarner
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#17
In reply to #16

Re: Can I Light Only One F40 Fluorescent Tube?

06/21/2012 12:28 AM

I have NOT researched at all on this, and I have no idea how it may affect the ballast and/or lamps, but an appropriate diode in series with one lead would only allow current to flow half the time. This is a common method to slow motors and dim incandescent lights; anybody know whether it will work for F40s? The lower P-P voltage might prevent the lamp from starting...

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Learner42
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#13

Re: Can I Light Only One F40 Fluorescent Tube?

06/18/2012 8:33 AM

The usage in the closet will be few minutes in a day. Is it worth the trouble?
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aurizon (1); dkwarner (2); Learner42 (1); lyn (1); Nothing is Impossible (1); ozzb (1); SolarEagle (2); StandardsGuy (6); Wal (2)

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