Battery powered pixels

[Habbosrus]

This may have been asked before. Could one power a pixel tester and a small strip of LED's with a small battery pack? Something like this? Battery pack found on Ebay.
Please understand I know nothing about this and my question or suggested battery pack may be completely ridiculous. I would like to find a way of doing this though.

 

[David_AVD]

I don't see why you couldn't use something like that with a small piece of 5V pixel strip or string.

The limiting factor will be how much current that pack can provide. I'd guess somewhere in the 0.5A to 1A range but you'd really need to check it out so you know how many pixels you could drive from it.

Be aware that the linked item doesn't include the Li-on cells; you have to buy them separately.

I have thought about using a battery pack for an LED adorned hat that is sync'd with a display.

 

[firebug]

While we are talking battery powered pixels, would a 12v vehicle battery (still attached to the running vehicle) suffice to run pixels in some sort of pattern? I'm assuming it would, but how far could I go with it? Could I have a pi or similar running a basic sequence?

Sorry to hijack your thread Steve, carry on mate...

 

[David_AVD]

While we are talking battery powered pixels, would a 12v vehicle battery (still attached to the running vehicle) suffice to run pixels in some sort of pattern? I'm assuming it would, but how far could I go with it? Could I have a pi or similar running a basic sequence?

The battery voltage of a running vehicle (car) is in the 13.8V to 14.4V range. This is up to 20% higher than the recommended 12V your typical strings and strips would be designed for, but may be ok.

The other thing that springs to mind is that a vehicle electrical system can have quite high voltage spikes on it. This can occur when fans cut in and out, etc.

I suspect one of those little 12V pixel testers and some 12V strings or strip would be worth giving a go as it's not a lot of money lost if it dies. Make sure you add a suitably rated fuse to the V+ line right near where you tap on the the battery supply.

 

[Habbosrus]

I have hooked up some lights to a car battery and it has run for a couple of hours. The battery wasn't in a car at the time though. I used one of Rays 12v pixel testers with the same thinking as David, it was only a short strip and a couple of dollars worth of pixel tester. Unfortunately I've lost the pixel tester somewhere. This is what got me thinking of powering some 5v pixels with one of his 5v pixel testers. I was thinking of lining a Santa hat or possibly an outline of a Santa suit. I then wondered if I could sync this with the show somehow. David, have you given any more thought to how you could sync the pixels on a hat? Is there a wifi enabled controller or something similar? I don't know if I'd be able to do it but I'm sure there are other ACL members who would have the ability and $$'s. Put your thinking caps on lads (& lasses).

 

[David_AVD]

There is a thread (or two) on the DIYC forum about wearable display pieces (hats, etc). I haven't followed it lately so not sure how they went with it.

It would be cool to have even just a few channels (for simple RGB lights) that were able to be sequenced along with the rest of the display.

I ordered a "USB Battery Bank" and a couple of cells off eBay today (prelim page here) to see how usable they would be. I like the idea of a plug-in battery pack that can be easily recharged.

As for the wearable controller, I guess the complexity of it would depend on transmission method (RF or IR), how many channels and what sort of update rate.

 

[fasteddy]

I used a small 7amp hour battery (used in alarm panels) to drive pixels to light up signs and to run a chase towards the direction i wanted the cars to go, like runway lights.
With a 5 metre strip you would get at least good 2 to 3 hours of running before you started seeing issues with the battery going flat so would last the duration of the show and light up the signage. I would then just use a 12v battery charger overnight to recharge the batteries ready for use the next day.

The battery is something like this http://www.ebay.com.au/itm/ALARM-BATTERY-7AH-AMP-HOUR-AGM-SLA-UPS-12-VOLT-12V-SPOT-LIGHT-DEEP-CYCLE-NEW-B-/291051798796?pt=AU_Car_Parts_Accessories&hash=item43c40a010c#ht_2494wt_918

 

[AussieDoug]

I ran a small set of lights for my donation box & the post off of one of these. It ran for the entire month & I never re charged it once. Would have only had 20-30 pixels so not a great load but they are only a small battery. Just wired it up to a cigarette lighter plug & a pixel tester.
http://www.supercheapauto.com.au/online-store/products/SCA-Jumpstart-900-Amp-Heavy-Duty.aspx?pid=283446#Recommendations

 

[firebug]

While we are talking battery powered pixels, would a 12v vehicle battery (still attached to the running vehicle) suffice to run pixels in some sort of pattern? I'm assuming it would, but how far could I go with it? Could I have a pi or similar running a basic sequence?

The battery voltage of a running vehicle (car) is in the 13.8V to 14.4V range. This is up to 20% higher than the recommended 12V your typical strings and strips would be designed for, but may be ok.

The other thing that springs to mind is that a vehicle electrical system can have quite high voltage spikes on it. This can occur when fans cut in and out, etc.

I suspect one of those little 12V pixel testers and some 12V strings or strip would be worth giving a go as it's not a lot of money lost if it dies. Make sure you add a suitably rated fuse to the V+ line right near where you tap on the the battery supply.

Is there a voltage regulator that I could place in line before the controller to curb fluctuations or spikes?

 

[David_AVD]

The other thing that springs to mind is that a vehicle electrical system can have quite high voltage spikes on it.

Is there a voltage regulator that I could place in line before the controller to curb fluctuations or spikes?

You could use a 12V to 5V DC-DC converter with 5V pixels and controller.

 

[firebug]

Hmm. Much food for thought. Thank you David. ..