Capacitor Blow Up

If you have an inductor somewhere down stream of the capacitor, you are probably seeing what is called "Inductive Kickback". Do a search on that term and you will see web pages with suggestions on how to deal with it, but it usually involveds a flyback diode and some form of suppressor.

you clearly need s flux capacitor from a quality dealer

but really........uplod a drawing with values (once you figure out how to attach and I'll be glad to redo your math and check your circuit, you can alsodownload free circuit software that will "test your circuit before you actually energize it to make sure it's right.....Google to the rescue

From your circuit description there is very little I can suggest about your capacitor failure. Clearly something is not right. I can think of plenty of dumb ways to misuse a capacitor in driving an LED (many by personal experience) but telling you a variety of bad ways to use a capacitor will likely not help you.

CR4 forum software can display images, like my friend to the left. (Acquired here.) To post an image click on the little green camera in the tool bar. Some browsers do not accommodate this tool bar. As for the posting of a full CAD, SPICE or other simulation file here, this is not done at CR4. Now you might post your file at another public site but you will certainly have to entice us with a better description to make us want to look.

can you show us the part of the circuit diagram from driver to led array, and you disconnect the led array when power is on?

Hi Epke,

I was trying to attach the circuit , but dont know how.

Could u tell me how to do that

Thanks

Why are you attaching, detaching the LED's with the power on, turn it off!

furthermore which LED driver IC are you using? In that specification it should be mentioned which capacitor should be used (read post 3)

Oh for pete's sake. As it was mentioned before, LEDs are current driven devices. Opening up the string is the death of them. Explain!

Can you reduce the voltage of the power supply that must go thru a constant-current circuit to drive the LEDs? The input voltage only needs to be say about 2.5V higher than the LED voltage. eg a 20W LED array can typically be driven with one of these circuits by inputting anything from 6V 4A up to 24V 1A. The LED array uses say 3V plus.

When you drop the load, the voltage probably rises to the maximum that the power supply can deliver. The constant-current regulator needs a minimum load to work.

You could have a minimum dummy resistor load which is always in circuit when the LEDs are removed. Also you could replace the capacitor with one of a higher voltage rating. Check the volts out when no LEDs are attached, and choose your cap to suit.

A similar problem happens with IC voltage regulators eg 7805. They need a minimum load. If the load is too small, they stop regulating the voltage down, and go high.

Tried many ways, didnt work, so i just put a switch between the ++ line and capacitor so that when the power connector is disconnected the switch is disabled via the connector and hence there no chance of the ++ input charges to collect on the plus polarity of the Al cap hence causing it blow up.

Thanks

Get your circuit diagram somewhere on your own PC as a .jpg, .bmp or .gif.

Click on the little green camera:-

Click on browse and navigate to your picture:-

Click on submit.