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amps
12-08-2012, 01:00 AM
Heyo! So in my obsessive planning for next year, I'm working out how to build a mini-Megatree (10ft) using dumb RGB strings for DIYLedexpress. Now normally, I would use cheap 2a Ebay amplifiers like I did with my RGB strips this year but the RGB strings I'm looking at are rated at 5V rather than 12v. That means buying the more expensive 5v capable amplifiers which would run over $160 (32 strings). Not to mention the bulk of all those extra boxes and the wiring.

I'm looking at the Simple Renard RGBW and the Ren48LSD. Each has a rating of about 400-500ma per channel but I'd be looking at running 1A continuous per channel. Running DCSSRs wouldn't be any cheaper so I'm wondering if there would be a way of modifying either existing board with a different transistor or FET that could handle the doubled load. Alternatively a low cost, 12 channel (4 strings from 3 outputs), medium current (1-2A) board to interface between the controller and the board. It would also make possible the running of higher 650-700ma RGB leds for flood light projects.

I know enough about electronics but not nearly enough to go picking replacement parts. Maybe this is a long shot or maybe something is already under works. Either way I figure I've got a year to ask questions and hopefully figure something out.

dirknerkle
12-08-2012, 01:37 AM
I'm going to guess that the traces on both the Simple and the LSD are designed to carry their stated loads and not twice that, so it might be a much more extensive mod to the board than you're anticipating...

Lionking_Tx
12-08-2012, 02:18 AM
OK, completely avoiding your power related question I would suggest to build the tree with intelligent strings rather than dumb ones.
It's not so much more money, but it will give you much more flexibility if you go the pixel route.

amps
12-08-2012, 10:14 AM
I've thought about pixels but two things hold me back. Though the cost isn't that much different, it would still add over a hundred dollars to my build cost and the controller would run nearly three times the cost of a Ren48 or similar. Also, I just don't like the pixel look. It's far too digital for my idea of Christmas. That's ironic of course considering all the blinking, flashing, rgb color changing I've already got going on :)

I just noticed a post in the original SimpleRGBW thread by Mac stating they were planning on upgrading the board for higher current next year. Maybe I can wait for that.

What about a daughter board with opto-isolators and mps650 transistors (also mentioned in that thread)? Or something like THIS MOSFET (http://www.taydaelectronics.com/t-transistors/fets-mosfets/irf520-irf520n-mosfet-n-channel-transistor.html)? Kind of a low cost, high channel DCSSR?

jaywalk101
12-08-2012, 11:24 AM
You could just get the e680 for 100 bucks and some ws2811 strings and just dumb them down...... prob be cheaper in the long run......

tjetzer
12-08-2012, 11:26 AM
I've thought about pixels but two things hold me back. Though the cost isn't that much different, it would still add over a hundred dollars to my build cost and the controller would run nearly three times the cost of a Ren48 or similar. Also, I just don't like the pixel look. It's far too digital for my idea of Christmas. That's ironic of course considering all the blinking, flashing, rgb color changing I've already got going on :)

I just noticed a post in the original SimpleRGBW thread by Mac stating they were planning on upgrading the board for higher current next year. Maybe I can wait for that.

What about a daughter board with opto-isolators and mps650 transistors (also mentioned in that thread)? Or something like THIS MOSFET (http://www.taydaelectronics.com/t-transistors/fets-mosfets/irf520-irf520n-mosfet-n-channel-transistor.html)? Kind of a low cost, high channel DCSSR?

If you add the cost of all the DCSSRs to the cost of the 2 Ren48s will be higher than the 2 E682s you would need to run pixels. You could also "Dumb down" the strings so the E682 addresses each string as 3 channels and they would run just like dumb strings. This would give you the option to run pixels individually in the future.

LightUp
12-08-2012, 11:26 AM
Electronics does offer many options - if you know the technology well enough.

You could use PC power supplies, which wouldn't cost much. A 5V section, depending on models, can drive 30A.

Yes, you could beef up circuit tracks the old fashion way. I've used 14ga (solid) house wiring by stripping the insulation and solder pieces along existing tracks where higher current is needed. This is not always possible due to circuit density. You will also need to know whether the connectors can handle the total current, so this is not a way to go for those uncertain about what they are doing.

I'm not current with all the REN board versions, but perhaps you could double the existing DCSSR boards but drive two from each channel. Now you have double the drive capability without messing with tracks, or modifying circuit boards.

A once you have a driver circuit you could hand-wire it on a piece of perf board for a die-hard DIY type of guy. :)
Much depends on what you are comfortable with and your skill level. This site has a lot a variety in how they want to go to get a job done.

james70818
02-09-2014, 01:12 AM
If you add the cost of all the DCSSRs to the cost of the 2 Ren48s will be higher than the 2 E682s you would need to run pixels. You could also "Dumb down" the strings so the E682 addresses each string as 3 channels and they would run just like dumb strings. This would give you the option to run pixels individually in the future.

Dave with DIYLEDExpress.com is making the new 60 amp RGB controller. It will give you 12 RGB outputs that have the mosfet built onboard. Basically it is half the LSD48 with built in SSR's. I plan to use them. Based on my experience this year, RGB's and Pixels have their pro's and con's. For color and ease of use the RGB's are just rock solid. With pixels, I had to do maintenance almost daily.

James