QA

Quick Answer: How Do Fluorescent Ballasts Work

In a fluorescent lighting system, the ballast regulates the current to the lamps and provides sufficient voltage to start the lamps. Once the arc is established, the ballast quickly reduces the voltage and regulates the electric current to produce a steady light output.

Can a fluorescent light work without a ballast?

Reverted question “ Can I make a fluorescent light work without a ballast?” yes, you can, but you need something to reduce the current as the bulb warms up. So, you can drive a fluorescent with a pulse width adjustable power supply, but this is what is in an ‘electronic’ ballast.

How do you know when a fluorescent ballast is bad?

If your fluorescent lighting is displaying any of the signs below, it could be a symptom of a bad ballast: Flickering. Buzzing. Delayed start. Low output. Inconsistent lighting levels. Switch to an electronic ballast, keep lamp. Switch to an electronic ballast, switch to a T8 fluorescent.

Why do fluorescent ballasts fail?

Flickering fluorescent tubes can cause the ballast to overheat and fail prematurely! When it’s too hot or too cold, the ballast can burn or fail to start your lamps at all. Heat combined with prolonged condensation inside an electronic ballast can cause corrosion and ballast failure.

How do electronic ballasts found in fluorescent tubes work?

An electronic ballast will convert power frequency to a very high frequency to initialize the gas discharge process in Fluorescent Lamps – by controlling the voltage across the lamp and current through the lamp.

What is the difference between a ballast and a driver?

Fluorescent ballasts provide an initial spike of high voltage, generating an arc that travels from cathode to anode within the discharge tube. LED drivers convert high voltage, ac current into the low voltage, direct current that LEDs are designed to run on.

What happens if you don’t use ballast?

Without a ballast, a lamp or a bulb will rapidly increase its current draw and it can become uncontrollable as well. When a ballast is present in a lamp, the power becomes stable, and even if such lamps are connected to high power sources, the ballast will regulate the energy and avoid the current rise.

Why are my fluorescent lights flickering?

If your fluorescent bulbs flicker, most likely the problem is with the bulb itself. If the bulb is very dark on either end, it may be defective and burned out. The best way to test the functionality of a bulb is to put it into a fixture you know works. Flickering fluorescent lights can also be a result of temperature.

Will a bad ballast burn out bulbs?

The ballast itself can go bad, which causes lights to flicker or even appear to be burnt out, when in fact they aren’t. They require maintenance and energy to power, on top of the power used to light the fluorescent bulb. They are a large part of the equation when using fluorescent lamps.

How do you know if it’s the bulb or ballast?

One probe of the multimeter should touch the hot wire connections, while the other touches the neutral wire connections. If the ballast is good, an analog multimeter has a needle that will sweep to the right across the measuring scale. If the ballast is bad, then the needle won’t move.

What are the signs of bad ballast?

2. Look for warning signs that the ballast is failing. Buzzing. If you hear a strange sound coming from your bulbs or light fixture, like a buzzing or humming noise, that’s often a sign your ballast is going. Dimming or flickering. No lights at all. Changing colors. Swollen casing. Burn marks. Water damage. Leaking oil.

How long do ballasts last?

According to the Certified Ballast Manufacturers Association, the average magnetic ballast lasts about 75,000 hours, or 12 to 15 years with normal use. The optimum economic life of a fluorescent lighting system with magnetic ballasts is usually about 15 years.

What’s inside a ballast?

A magnetic ballast (also called a choke) contains a coil of copper wire. The magnetic field produced by the wire traps most of the current so only the right amount gets through to the fluorescent light. That amount can fluctuate depending on the thickness and length of the copper wire.

What’s the difference between magnetic and electronic ballast?

A magnetic ballast uses coiled wire and creates magnetic fields to transform voltage. An electronic ballast uses solid state components to transform voltage. It also changes the frequency of the power from 60 HZ to 20,000 HZ or higher depending on the ballast.

What voltage comes out of a ballast?

Fluorescent lamps use a ballast which transforms line voltage to a voltage to start up and operate the lamp(s). Newer fluorescent ballasts are usually rated for both 120 volts and 277 volts. Some are rated for only 120 volts, others for only 277 volts (used in commercial environments).

How many ballast are in a 4 bulb fluorescent light?

A 4 lamp fixture with two rapid start ballasts can be replaced with one 4 lamp instant start ballast. As seen below, connecting the 4 lamp instant start ballast to the four lamps can be a bit confusing.

How much energy does a ballast use?

Electronic Ballasts Standard ballasts consist of a core and coil assembly. On a typical fixture with two 4 foot 40 watt T-12 fluorescent lamps, the ballast consumes about 13 to 16 watts of electricity. Thus the total consumption of the two lamps plus the ballast is about 93 to 96 watts.

Do LED tube lights need a ballast?

No LED bulbs require a ballast, although some are engineered to work with an existing ballast. You will find ballast-compatible or “plug-and-play” LEDs that are designed to replace linear fluorescents, compact fluorescents, or HIDs. Incandescent and halogen lamps do not require a ballast.