How a Fluorescent Lamp Turns On

That Bush reference was wonderful, I appreciate your sense of humor, and your content, thank you for doing what you do.

yes,you are right,this way for teaching is good.But I mean I like the channel to show us the beauty of physics or some interesting physical phenomenon.(like Tesla speaker,electrical rail gun..) then teach us the physics knowledge behind it.

So how does this differ from neon signs?

it probably looks at the current through the lamp, if it is running, there will be current

ElectroBOOM [Mehdi Sadaghdar]

Huh, kinda want to see how the ballast looks on a scope. Wonder how it figures if the lamp is lit or not -- does it just hold a constant time at a high voltage, then drop to normal mains until it turns off?

Ah right! I thought you were talking about when I was speculating about a capacitance in the lamp!

ElectroBOOM [Mehdi Sadaghdar]

With magnetic reactive ballasts, a capacitor is usually paired with the inductor for power factor correction. The starter includes a small capacitor for EMI suppression. Neither capacitor is necessary for operating the lamp, but this would result in a poor factor (larger businesses pay extra) and radio interference.

Seán Byrne

which capacitor? there is no capacitor

ElectroBOOM [Mehdi Sadaghdar]

You should explain the capacitor.

The idea behind the style you're talking about, is to show people that you don't need to be a genius to figure out how things work, and that you could do it yourself if you wanted to.It's to instigate people to look for their own answers, without taking everything at face value.

Blackcorvo

Super interesting video, this!

Luit van Drongelen

Sounding good, fam!

emmmm.....I have learnt it in high school physics. And the style of this video reminds me of my high school physics class(some bad memories). Just teacher pretended not to know how it works, and encourage students to find the point .. Personly, I don't like the style.I perfer to just tell us how it works,the laws which it follows,and more about it.(The previous video style) Of course, just personal opinion.

My favorite video in a while. You took something that I always assumed was pretty simple and showed just how complicated it really is, but in a way I could understand. Can't wait to share this one!

Mark

big clive has you sorted Mehdi... <a href="https://www.youtube.com/watch?v=hjphxq9nUrA" rel="nofollow noopener" target="_blank">https://www.youtube.com/watch?v=hjphxq9nUrA</a>and <a href="https://www.youtube.com/watch?v=qLaD11LITbQ" rel="nofollow noopener" target="_blank">https://www.youtube.com/watch?v=qLaD11LITbQ</a>

Happy Holidays + Happy New Year..... NOW GIMMI SOME FREEBIES.....

We changed out all our indoor (And most outdoor) fluorescent tube lights to LED's a few years ago. The nice part is that you just cut the ballast out of the circuit. Ballasts are expensive...

Loved it! Always wondered how they worked.

I work with stage spotlights and moving lights, and they get their light sources started in much the same way! Thanks for showing off the details of those circuits; great video.

zach

Awesome!

I never really understood or thought about this too. Very educational and entertaining too. Thank you Mehdi.

Maybe you could make a video about the difference between ballast, that power flourescent lights, and drivers that power led’s. In fact what happens when you switch them?

I always thought that the system was a few thousand volt run circuit with a higher starter voltage....how about that.

Magnificent work, Mehdi!

Jason Hoffman

Thanks. I've replaced dozens (hundreds? who can keep count) of those ballasts over the years, without ever knowing what special magic they were doing. I always assumed it was called a ballast because they weighed about the same as a brick and weren't good for anything else other than tossing in the hold of a ship when they went out.

I think I measured it and it said 110V, might be wrong though, or might not be a sine wave anymore

ElectroBOOM [Mehdi Sadaghdar]

So what voltage was going across the filament leads using the store bought ballast? Inquiring minds want to know!

I don't know how you kept a straight face while "exciting" the lamp! Lol. Great video!

The start reminds me of a neighbour who had a LPS (low pressure sodium) street light that wouldn't light. Unlike fluorescent lamps, most LPS bulbs typically use the same bayonet cap fitting as regular light bulbs here in Ireland, so he thought he could test the bulb in a regular light fixture. Sure enough it went bang!

Seán Byrne

Great video! I've always wondered how those work... Not anymore!

Do a giveaway of fluorescent lamps!!! GIMME DA LAMP!

Dibya Jyoti Roy

That was a very nice video. Also, I'd like to thank your wife for still letting you anywhere near something that has more power than a coin cell. :)

Marco Vujevic

Excellent Mehdi! Funny as always, and superb video :-)