LED wiring

[BackinBlack]

If all the LEDs were identical then series with a current limiting resistor would work, otherwise the current flowing would be governed by the lowest rated LED, the higher current LEDs would just be a glimmer. The "correct" solution would be an SBEC (more efficient) with each LED having its own current limiting series resistor.

But, hey, if the OP is happy and the LEDs light up, object achieved?

[Former Member]

[This posting has been removed]

[Zflyer]

My original question was would it work.

I apologise for being a dumb brum with no knowledge of electronics.

I mistakenly believed that as the balance leads were connected to individual cells they would carry single cell voltage, clearly that is not the case as the voltage increase across the cells.

Making that assumption I thought by distributing the load across the cells I would help in balancing the lipo.

I have listened and will obviously use another more practical solution.

A little less judgement and presumption (as I did with the voltage) might not go amiss

[FlyinFlynn]

So Z, exactly which LED's did you buy? The complete answer to that question will probably illicit the correct response from the gathered intelligentsia.

[Mike T]

Posted by Steve J on 10/08/2020 16:03:46:

 

That is how the nose light on my FunJet is done, balance connector to LED driver to 1W LED.

Thanks Steve (and BiB). That looks like a cheap experiment, but the ready to go setup linked by BiB looks a bit of a bargain!

Edited By Mike T on 11/08/2020 12:00:39

[Former Member]

[This posting has been removed]

[BackinBlack]

Posted by Steve J on 11/08/2020 12:14:25:

Posted by Mike T on 11/08/2020 11:59:53:

Posted by Steve J on 10/08/2020 16:03:46:

That is how the nose light on my FunJet is done, balance connector to LED driver to 1W LED.

That looks like a cheap experiment, but the ready to go setup linked by BiB looks a bit of a bargain!

IMHO there is very little point in putting 30mA LEDs on models (unless you are putting a lot of them on).

I'd agree with that. For normal daylight use once they're more than a few feet away you can't really see that they're on. The "Superbright" Landing lights are quite different, easily visible if you're in the beam even in full daylight.

[Allan Bennett]

Posted by Zflyer on 10/08/2020 23:46:01:

.... I mistakenly believed that as the balance leads were connected to individual cells they would carry single cell voltage, clearly that is not the case as the voltage increase across the cells.

Making that assumption I thought by distributing the load across the cells I would help in balancing the lipo. ....

Your belief is not mistaken

Each adjacent pair of balance leads would give you single-cell voltage. So, using your original diagram, red to green would give 3.7v nominal, green to yellow would give 3.7v nominal, and yellow to black would give 3.7v nominal. So if you had only three LEDs you could connect them between those three pairs of leads and your pack would stay balanced -- so long as the LEDs each draw the same current.

In practice a 30mA (or whatever small current) LED is not going to have much effect on a battery that's supplying probably 10A and upwards to the motor. The main concern would be forgetting to disconnect the LEDs after a flight.

[Mike T]

Posted by Allan Bennett on 11/08/2020 13:33:33:

The main concern would be forgetting to disconnect the LEDs after a flight.

The beauty of using the balance plug. You have to disconnect it to get the pack out of the plane.

Re brightness, I'm not fussed about all the colours - I've noticed their ineffectiveness at 5+ metres on friends' aircraft. But I DO like the idea of an 'eye of Sauron' type beam emanating from the nose...