Fitting a headlamp, as a beacon, to a P3Adv

[Deleted member 120647]

I have ordered a headlight of the type shown in the attachment. The intended use is as a 'beacon' rather than for illumination of a 'subject'.
In the advert the wiring for this is shown running on the outside of the body and the power connection is obviously not switchable. I am wondering whether it is feasible to connect the headlight in place of or in parallel with, the front LEDs which are switchable?
Does anyone know the design limit for Amperage in the front LED circuits? I have not yet received the headlight so do not yet know its current draw.
In the event that the required current is too great, would using a relay tripped by the supply to the front LEDs be feasible?
I realise I might have to open the body shell to do this.
Thanks

 

[Capt KO]

There was a P4 listed the other day that had a wire hanging out of it that nobody could figure out what it was for. It was probably for your headlight. Let us know how this works out but I can't help you.

 

[Steve7777]

I have ordered a headlight of the type shown in the attachment. The intended use is as a 'beacon' rather than for illumination of a 'subject'.
In the advert the wiring for this is shown running on the outside of the body and the power connection is obviously not switchable. I am wondering whether it is feasible to connect the headlight in place of or in parallel with, the front LEDs which are switchable?
Does anyone know the design limit for Amperage in the front LED circuits? I have not yet received the headlight so do not yet know its current draw.
In the event that the required current is too great, would using a relay tripped by the supply to the front LEDs be feasible?
I realise I might have to open the body shell to do this.
Thanks

I've had one similar to this on my P3p for quite a few years BUT mine has and on/off switch and an inline transformer from battery voltage down to 5V, which is what many LEDs of this type run at, although some are designed for 12v and other voltages. It's bright, works fine and it's invaluable for helping to work out orientation by LOS at long distance.

My guess is that unless there's some electronics hidden somewhere that I can't see in the pic, that for good or bad it will be running at main battery voltage. The metal plate with two holes in it is designed go through a ventilation slot and to slip over the internal battery terminals before inserting the battery and I've had no problems in running mine this way. With mine, the controller circuit board is fixed to the outer shell with double-sided tape. These LEDs use minimal power, so I don't think worries about how many amps are going to be a problem. Probably easier to just install it as it was designed for though - and just pull the plug to switch it off or wire in a micro-switch. The power usage is next-to-nothing and will not noticeably affect flight times, so remote switching via LEDs isn't really merited, IMHO.

 

[Deleted member 120647]

Thanks for the description Steve.

 

[Steve7777]

Thanks for the description Steve.

OK - I've just added a bit more to my post, you may need to reload to see it... The light IS very bright though, even in daylight - a very useful addition when flying LOS only.

 

[Steve7777]

This variant has the inline controller, as I described above.

Professional Standard White RC Drone LED Camera Head Light for DJI Phantom 3gr for sale online | eBay

Find many great new & used options and get the best deals for Professional Standard White RC Drone LED Camera Head Light for DJI Phantom 3gr at the best online prices at eBay! Free delivery for many products!

www.ebay.co.uk

 

[N017RW]

The only way to use the front LEDs for switching auxiliary circuits is with an external interface which senses the LED status (photodiode/transistor, photoresistor, etc) and then provides the switching to drive an aux. load.

 

[Deleted member 62848]

Ok,,me has had these in past and was not impressed due to it creating heat when on,unlike other strobes or headlight sets,,this light came with its own batt 7.2 lipo and just clips on the leg as power source,,,I have since modified this unit to work a strobe light,,,,,have tried many lights and this one not a favorite,,,especially not good how yours come with no power source since it will contribute to drain your phantom batt ,,,bottom line they work but heat up,

 

[Deleted member 62848]

This how mine arrived,from ebay but not sure if still available ,this screenshot of my ebay record

 

[Steve7777]

Ok,,me has had these in past and was not impressed due to it creating heat when on,unlike other strobes or headlight sets,,this light came with its own batt 7.2 lipo and just clips on the leg as power source,,,I have since modified this unit to work a strobe light,,,,,have tried many lights and this one not a favorite,,,especially not good how yours come with no power source since it will contribute to drain your phantom batt ,,,bottom line they work but heat up,View attachment 113073View attachment 113072

I suspect that the reason it gets so hot is because it's being run on 7.2 volts (or even 8.4 volts if the lipo's fully charged) when it's only designed for 5 volts.

If you're handy with a soldering iron you can construct your own power feed, as I mentioned, from the battery terminals, with a BEC transformer inline to bring the battery voltage down to 5 volts.

Mini uBEC SBEC BEC 3A 0.8-20V DC Adjustable Step Down Power Supply - FPV PDB 5V | eBay

2x Mini uBEC step-down modules. Output Current: Rated Current 2A (3A max. heatsink required). Module Properties: Non-isolated step-down module (buck). Output Ripple: less than 30mV. Battery life is not warranted and will vary depending on usage.

www.ebay.co.uk

 

[Deleted member 62848]

Yeh my post number 9 show original,,5volts no wonder it got hot,was unaware on that,cheers

 

[Deleted member 120647]

N017RW, using a photodiode wasn't something I had thought of, thanks for that!

Steve7777 the ebay link you show is coincidentally the first advert I saw for these LEDs but unfortunately then dont ship to my bit of the UK so I had to look elsewhere.

Ian, thanks, the heating problem has been mentioned in a PM from someone.

Steve7777 when it arrives I will check currents and what voltages if I can. I wonder if my old analogue Avo is still working??? Actually it will probably out last my DMM lol

 

[N017RW]

Great. It has been discussed here in the past and since you're recently registered here you may not be aware of this option.

 

[Deleted member 120647]

Ok so it turned up today, can I just check that all the yellow rectangles in "LED board" are LED's?
The output at 16.9V is seen through two filters ND4 & ND8 and a pair of sunglasses.
The filtering is to allow the camera to distinguish individual LEDs whilst still being able to see the voltmeter. At 16.9V this was drawing around 71mA

 

[Steve7777]

Ok so it turned up today, can I just check that all the yellow rectangles in "LED board" are LED's?
The output at 16.9V is seen through two filters ND4 & ND8 and a pair of sunglasses.
The filtering is to allow the camera to distinguish individual LEDs whilst still being able to see the voltmeter. At 16.9V this was drawing around 71mA

Yes, they should all be lit-up LEDs and from the photo it looks like some of the LEDs are unlit. Is that correct?

If so, then I'm afraid you either have some bad LEDs or maybe some bad soldering. It's not that uncommon to have things which are made by the million, literally for pennies, turn up dead, or part-dead on arrival.

What can you do? What was the Ebay seller's feedback like? If it was much below 100% then look through the bad feedback and you might spot a non-reassuring pattern. However, you can contact the seller and explain the problem and they probably won't be surprised and will offer to ship a replacement (which may well never arrive) or you can politely ask for a refund, which is easy to see if it has been given within a few days. If no refund arrives in PayPal in a few days then ask Ebay to intervene and probably you will eventually get your money back.

Or you can just put it all down to experience....

 

[Deleted member 120647]

Re "looks like some of the LEDs are unlit" I am glad you said that, only 7 light fully, 3 may be glowing but it's dimly if they are. With the naked eye the lit ones are enough to leave a temporary blind spot if you make the mistake of looking straight at it when at arms length, whoops.
I will try checking connections with the meter, as much to see how these are connected as anything else.
I am experienced with defective items via ebay lol. It will be a polite message to the seller and take it from there.

 

[Steve7777]

The ones that are going stellar are probably running over-voltage, of course. They'll probably burn out if you keep connecting it.

I've ordered hundreds of items from Ebay.co.uk and, happily, I've not had many such problems. But of course, you sit and wait expectantly for delivery from China and when it arrives after some time and it's duff, it's all a bit disappointing.

However, any such problems are all the more annoying for me as once I have placed an order it is delivered to a holding depot for a courier in London, who then cheaply trucks all my orders to me in Eastern Europe, taking about one week to do so.

So because of the extra delay ordering from China etc would cause, I usually order only from the UK - at least, as far as I can ascertain when ordering.

But there are some very good sellers based in Hong Kong/Singapore/China/Taiwan etc and some of they reliably give a 7-day service from order to delivery in London. That's good - but I don't take any risk of getting caught up with customs protocol by buying higher value goods from outside the EU...

Who knows what BREXIT will bring though..

 

[Deleted member 120647]

"Who knows what BREXIT will bring though.. " A total f up more than likely

 

[Deleted member 120647]

If of use these are the tracks etc. as I can find them, 6 parallel branches with 4 diodes in series in each branch. It seems odd that I have 7 fully lit. It looks as if B1 to B4 are lit and W1, W2 & W4 are lit but W3 dimly glows. The other partially glowing track is the purple one.

 

[Nightwolf]

With the naked eye the lit ones are enough to leave a temporary blind spot

you're already deaf, try not to go blind as well ehh