Electronic Fluorescent Lamp Ballast

[mysterfxit]

My wife has a make-up mirror (zadro clv581) that stopped working. It was quite expensive and I'd hate to just toss it.

It has a circular flourescent bulb, and switch for 3 levels of brightness. It's completely dead, not even a flicker.

The components look OK visually. Can anyone give any advice on how to go about finding what's wrong here?

Thanks.

[retiredcaps]

Re: Electronic Fluorescent Lamp Ballast

Maybe unscrew TG1 and measure the DC voltage across some of those electrolytic caps to see if you even get power?

[cmj21973]

Re: Electronic Fluorescent Lamp Ballast

Post a picture of the solder traces for both boards, please.

[Rob Northen]

Re: Electronic Fluorescent Lamp Ballast

My wife has a make-up mirror (zadro clv581) that stopped working. It was quite expensive and I'd hate to just toss it.
Thanks.

Toss wife, it will save you lots of money

[Evil Lurker]

Re: Electronic Fluorescent Lamp Ballast

Start by yanking ou the two transistors and test them

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

I attached a composited photo of the fronts and the backs of the boards. I mirrored the back pics so that each everything lines up as if you were looking through the board from the top.

L3 is kind of melty looking.

[GeX]

Re: Electronic Fluorescent Lamp Ballast

Check the C9 and C10 capacitors.

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

I'm new to electronics repair so I'm trying to test the components while still on the board

Testing the capacitors with a multimeter (set to ohms) C10 is the only one that didn't do a low resistance kick then fade to open. It stayed at a low resistance value (needle spiked.)

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

The Transistors are labeled 13003 LZA.

I tested the transistors with multimeter set to ohms and they both give the same results. Current passes both ways between pins 1-3 and only in one direction between pins 1-2 and 2-3.

[b700029]

Re: Electronic Fluorescent Lamp Ballast

You need to test components out of circuit for accurate results.

[Longbow]

Re: Electronic Fluorescent Lamp Ballast

You need to test components out of circuit for accurate results.

Technically this statement is true. To get all of the exact component specifications, run leakage tests, voltage break down tests, run curve traces showing hfe, linearity, etc. etc. then yes the component should be removed from the circuit. On the other hand, 99% of effective troubleshooting can be and actually IS done in the real world with parts in circuit. Not only does desoldering and resoldering risk damage to the pc board and components, but it takes a lot of time and is rarely necessary.

[GeX]

Re: Electronic Fluorescent Lamp Ballast

Let's make a long story short: change C10 with a compatible one (value/voltage). I bet on this.

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

Thank you. The only markings on C10 are 608J 1000V. What Farad value is that? And I'm guessing this is a polyester film capacitor?

[Toasty]

Re: Electronic Fluorescent Lamp Ballast

Check that 8 please. Sure it's not a 3 ? Or the whole number is not 683?

608J would be 6000 uF, 5% tolerance. (it's a *tad* small in size )
603J would be 0.06 uF, 5% tolerance. (aka: 60 nF or 60,000 pF ) The size would be more correct.

"68" is a more common value

Usually caps run in numbers such as:
33, 47, 68, 100
-or-
33, 47, 56, 68, 82, 100

Actually (probably) a metallized polyester film.

Toast

PS: Can you post a broader picture/view so the input and outputs are more understandable. I can't be sure which is 110v in, output to lamp, dimmer switch. Thanks!

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

Thanks. I'll check the numbers again and take another photo when I get home tonight.

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

Here's a wider photo and a close up of C10.

[Toasty]

Re: Electronic Fluorescent Lamp Ballast

6n8J = 6800pF or 0.0068uF, 1000v, 5%

Thanks for the pics!

EDIT: You are reading 0Ω across that cap? Try unsoldering one leg and testing it. If it's good then, perhaps the bulb is shorted? Does it glow or flicker at all?

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

Yes, IIRC there appeared to be very little to no resistance. I'll try testing it unsoldered it this weekend.

The thing is completely dead. No flicker, glow or anything.

Thank you all very much for the help!

[Toasty]

Re: Electronic Fluorescent Lamp Ballast

Essentially:



Where Cr is C10 and C1 & C2 are C5 & C6.

[mysterfxit]

Re: Electronic Fluorescent Lamp Ballast

Thanks.

Funny. I don't know if I can get to desoldering tomorrow night, so I was going to ask if you can explain to me a bit what's going on in this thing.

I know the diode symbols and I'm familiar with rectifiers from working on motorcycle charging systems. C's are capacitors, but why is Cr not numbered like the rest. What is L, B and M?