QA

Quick Answer: Why Do Fluorescent Lights Flicker

In your lighting system, the ballast regulates the current flowing to the fluorescent lights and provides the voltage needed to start the lamps. The ballast takes in electricity and then regulates current throughout the bulbs. This is why a degrading ballast will cause the fluorescent lights to flicker.

How do I stop my fluorescent lights from flickering?

Brush dust out of sockets, then reseat firmly. If the tube still blinks when the light is turned on, wiggle it a few times while the light is on to see if this cures the problem. If not, take the tube out and inspect sockets closely to see if spring contacts are bent or corroded.

Is it normal for new fluorescent bulbs to flicker?

It is normal for the light in new fluorescent tubes to flicker or appear to swirl in the first 100 hours of operation. If an older tube exhibits these symptoms, turn off the switch, remove the tube, then clean the ends thoroughly.

Can a bad ballast cause flickering?

Dimming or flickering If your bulbs are very slow to reach full brightness or strobe periodically, there may be a problem beyond the bulb. Water-damaged or faulty ballasts often struggle to regulate current.

Why do fluorescent lights flicker when turned off?

When a CFL flickers, the cause is usually in the light switch, which is either a dimmer or a switch with an illuminate rocker. Illuminated switches pass a small amount of current even when they’re turned to the “off” position, which is enough to charge the capacitor in the CFL and cause a momentary illumination.

How do you tell when a fluorescent bulb is burned out?

How to Tell If a Fluorescent Tube Is Bad? Check the ends of the tube. If they appear darkened this indicates the bulb is burned out. Rotate the tube in the fixture if the bulb is not darkened on either end. Remove the bulb from the fixture if the bulb is still not illuminating.

How long do fluorescent tubes last?

LED tubes last an average of 50,000 hours (roughly 16 years) while fluorescent T8 tubes last an average of 25,000 (roughly 8 years).

Why do light bulbs flicker when turned on?

Flickering or blinking lights are usually caused by one of four things: Problem with the bulb (not in tight enough, wrong bulb type for dimmer switch) Faulty light or fixture switch. Appliance pulling large amounts of current on startup, causing a voltage drop.

Where is the ballast on a fluorescent light fixture?

Locate the wiring cover plate, usually in the center of the fixture. On either side of the cover, there will be tabs that catch in slots in the fixture. Squeeze the sides of the cover inward to slip the tabs out of the slots, and pull the cover down. This will expose the ballast and its wiring.

How can you tell if a fluorescent light 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.

How much does it cost to replace a ballast in a fluorescent light?

A replacement ballast costs about $10-25 depending on capacity and brand. The bite is that an electrician trip charge (which includes 30 or 60 minutes work) is going to be $75-150 probably – for about 5 minutes work on each light fixture.

How do I know if my fluorescent tubes are bad?

Look for dark areas at the base of the bulb. When bulbs age and have been used for a long time, brown spots will appear. If darkness begins to form at the ends of the tube, the bulb may be near its end. While they may still light, they are wearing out and will die soon.

Can flickering lights cause a fire?

Minor changes in your home’s voltage are normal, but flickering lights may indicate abnormal fluctuations. Abrupt changes in voltage from low to high can damage electronics and in rare cases cause an electrical fire.

What causes multiple lights to flicker?

One explanation would be that you have loose service conductors in your central electrical panel. Some other possible explanations for lights flickering all over the house include faulty connectors, worn down wiring, and improperly connected wiring.

Why are the lights in my house pulsing?

Light bulbs that are loose in their sockets will receive an inconsistent supply of power, which can cause a flickering effect. This problem has a simple fix: Turn off the light. If it is equipped with an incandescent or CFL light bulb, wait for the bulb to cool down before handling it.

Can 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 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.

How do you check for a bad 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.