Things burning out for no real reason...

[Eco]

I had a saber that was driven by a buckpuck, powered by a 7.2v NiMH pack. For some strange reason, the last time I charged the batteries via charge port, the buckpuck burned out. (And the charger does have a DC converter in it)
Any idea what went wrong?

And, this one's got me in a real funk: as a temporary thing, I was going to drive my blue P4 on 2 AA batteries (2x Single AA batteries wired in series), well below the minimum voltage, direct drive style, no resistor.
The LED didn't light, at all. Once I put the LED back into it's saber, it didn't light there, either. So, I burned out my LED with less than the forward voltage.
Can someone please tell me what happened here?

[Revan]

what led are you using? and r u sure you got your polarity correct on the set up with the recharge port?

[Eco]

Oh, I'm sure the polarity is correct. I've been using that in my main saber for two months now.

The LED that accompanied the 7.2v pack was a Lux V, and the LED that burned out, as I stated, was a P4.

[Revan]

ok. well then i don't know what the problem is. maybe some one else will ;)

[Novastar]

Having the wrong polarity for an LED should not damage it (technically)... so I'm just saying that isn't a problem...

Feeding a P4 (blue) 3.0v should NOT destroy it... although I don't know if it would light up with 3v--even a little bit. It depends.

If the LED was not on a heatsink at the time of feeding it 3v... you can still run the risk of destroying it. And certainly it would not survive long if you gave it its fwd voltage or more (sans heatsink).

Buckpuck--if the buckpuck was still "in the circuit" when the batteries were being charged... and the buckpuck was barely rated for 7.2v... it could have been killed by the charger.

I can tell you all something you won't want to hear: I somewhat damaged a CF by charging its batteries with a smart charger... but the circuit was never shut off or disconnected by the kill switch: the kill switch somehow didn't work right with the charger attached (although the kill KEY worked, arrrgh). Anyhow... "topping off" CF for several hours didn't leave it happy. Long story.

The moral is: be very careful and very sure about your wiring prior to connecting batteries/turning on the circuit. There is no harm in double + triple + quadruple checking EVERYTHING first.

[Jedi-Loreen]

If you're using a buck puck from the Store, they are rated to handle up to 32V, so that doesn't make sense that one of those would "burn out".

I have heard that P4s can be kind of sensitive though, especially the red ones.

[Eco]

The weird thing about the charge port on the green saber was that it suddenly changed from just a recharge port to charge port/killswitch. Out of nowhere when I plugged in the charger the saber turned off. Still came back when I took the charger out, but it wasn't wired up to be a killswitch before. Checked for shorts and didn't see any.
I do wonder if the AC/DC inverter in the charger busted somehow and started feeding my saber unregulated AC current. The charger got really hot the last time I charged it.


The P4 was on the heatsink, and even still in the bladeholder, never even touched the LED proper until I was testing continuity after it burned out.

So far, I've burned out every single P4 I've gotten my hands on, save one. They do seem to suffer from being sensitive.