LightingCommon
Fluorescent fixture
Also called tube light, shop light, ballast.
A magnetic ballast is a heavy choke. An electronic ballast is a mains high-frequency supply with little salvage value. The tube contains mercury and is recycled whole.
A donor is the dead machine. The parts below are what is still worth removing from it. “Leave it” is a part that is physically in there and should stay in there: too dangerous, too worn, or only useful as part of a repair you are not doing.
A scrapped machine is a box of parts that failed at different times. The reason it was thrown out is often one bad piece. The motor, the cord, the supply, and the screws are frequently still good. This index says which is which.
Why it is in the trash while the parts are not
The tube blackened, or the ballast hummed. The fixture body is often fine.
Before you open it
Do this while it is still unplugged, cool, and not leaking. Power off at the switch and the breaker if it is hardwired. Tubes out, carefully, before the fixture comes down.
Where the dead machine usually is
- Garage and shed — In the house
- Remodel and construction dumpster — Curb
- Office cleanout — Commercial
Remodel dumpsters. Tubes are hazardous waste, intact.
How it comes apart
The ballast is the heavy can. If it is light, it is electronic.
Tools: Screwdriver, Meter.
Words on this page
- mains
- Ordinary household wall power. It can kill. Unplug before you open anything that used it, and do not experiment on live wiring.
What to take
The table is the short version. The notes under it describe that part inside this machine, not only the general description.
| Part | Call | How many | How often | Where to look |
|---|---|---|---|---|
| Power inductor | Worth pulling | 1 | sometimes | Magnetic ballast. |
| Film capacitor | Bonus | 1 | sometimes | Older ballasts. |
| Fuse | Bonus | 1 | sometimes | Inline. |
| Enclosure | Worth pulling | 1 | always | The reflector. |
| Signal and hookup wire | Bonus | a run | usually | The leads. |
Worth pulling
A large iron choke. Useful as a choke, not as a toy.
Magnetic ballast.
Heavy.
Humming ones may be failed.
A ready shop-light body if you are converting it to LED tubes on purpose.
The reflector.
That conversion has a standard method. Do not invent a floating ballast.
Good.
Bonus
A power-factor capacitor.
Older ballasts.
Read it. Discharge it.
Aged.
Read it.
Inline.
Test.
Good.
Mains-rated, if it was mains-rated.
The leads.
Do not downgrade it into a mystery bin.
Good.