Hi Guys, firstly can i say i LOVE the forum, LOADS of amazing help and advice and everybody seems so helpful. I have a project that I'm trying to pull together, and was wondering if anyone could see a weak link that will fail or wont work and general advice on the project. I need to create some free standing boxes, using WS2801 pixel strip LED tape (picture attached), (id also like some advice as to whether i would gain anything switching to the WS2811 chip) i managed quite well to get this all working using a mains power supply, now for the interesting part... i need it to run off batteries!!! the idea is to run the unit from a battery big enough to have a run time of circa 6-8 hours running animations, here is the list so far that i have pulled together to try to get this to work Battery http://www.batterymasters.co.uk/Product-Yuasa-NP24-12I,-12V-24Ah-Sealed-Lead-Acid-Battery-(L(mm)-W(mm)-H(mm)-166-175-125)_1767.aspx 12V - 5V DC-DC converter http://www.ebay.co.uk/itm/DC-DC-Voltage-Step-Down-Converter-Buck-Module-12V-24V-to-5V-5A-25W-Waterproof-/320910878846?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item4ab7c7687e DMX controller http://www.ebay.co.uk/itm/DMX-512-SPI-decoder-to-WS-2801-led-controller-miniDMX-2801-1-0-/320991177470?pt=LH_DefaultDomain_0&hash=item4abc90aafe Wireless DMX receiver transmitter http://www.ebay.co.uk/itm/3-sets-OEM-PCB-Modules-Wireless-DMX-LED-Lighting-Controller-Transmitter-Receiver-/181174061275?pt=UK_Sound_Vision_Performance_DJ_Parts_Accessories&hash=item2a2ed0c8db I managed to get the whole system working correctly using the wireless DMX running the Chamsys software (which i know very well so will be my software of choice) My question really relates to the battery side of the project, will the 12v with the DC-DC step down converter work? i was planning on using x2 for the strip, half the length off each converter, then i would power the DMX decoder direct from the 12v side and the Wireless DMX from one of the converters. Sorry in the very long first post, any help would be greatly appreciated. Mike
Welcome to ACL This idea should work, I ran some lighting from batteries last year but they were only 7.5amp/hour batteries and I seemed to get about 3 to 4 hours of use before they needed charging. What you need to work out is what size battery is suitable to give you constant power for 8 hours.
Hi there, and thanks for having me I intend to run the strip at around 40 percent intensity, this i will do as an inhibit through the desk so that should help in terms of current draw on the batteries Is there any advantage to using the ws2811 chip as opposed to the ws2810? Mike
2811 is now the choice, the main difference is that the 2801 has an extra cable for the timing where as the 2811 has 3 wires only as the timing is within the data. Both are 8 bit per colour. If you are wanting to use single LED control then the 2812B is a good choice which is effectively a 2811 chip that is embedded into the LED. Running at 40% intensity will definetly extend the battery life.
Thanks for the quick response What are the advantages of the WS2812b over the WS2811? will it be more efficient as it is embedded into the LED? I have just looked for the Ws2812b in Ray Wu store and they dont seem to have any DMX decoders to suit, will a WS2811 decoder do the same? Mike
The 2812b uses the exact same data as the 2811 so any 2811 controller will work with the 2812b, the 2812b definition means its embedded into the LED and the b means its a second revision which includes better efficiency and reverse polarity protection.
Thankyou for all your help, Ive ordered some bits from Ray Wu and will see how i get on. If anybody else has any input re the battery side that would be amazing Mike
