Another LED tape/DMX question

[bruce]

There's been a fair amount of chat about LED tape over the years, and some product recommendations. However, some of these are a few years old, and there are maybe better answers now. So I thought I'd pose a few questions and get the answers into one place.

 

I've got an application where I'll need about half a dozen 2m lengths of RGB (or RGBW) tape. Needs DMX control.

 

So, the questions:

 

1. What sort of tape are people commonly using these days? 5050? 3528? Something else? I'm looking for something reasonably bright.

 

2. There are loads of boxed DMX-LED drivers available on Ebay from China. Most look to be the same design, and come in at about a tenner. Are these OK?

 

3. What sort of PSU should I use with these drivers?

 

4. Any recommendations for a suitable plug/socket to link the unit with the tape and the driver? It needs to be a pluggable connection.

 

 

Any other useful info would be appreciated.

[timsabre]

5050 tape with 60 leds/metre is brightest. You can also get 30 leds/metre. 3528 is cheaper but not as bright.

The chinese drivers seem to be fine as long as you don't mind slight visible steppiness in the bottom few DMX levels.

I just use a generic 12V switch mode psu brick to run tape. 5 amps is enough for a couple of metres if you don't put everything on full.

A lot of the tape uses a pinstrip-type connection for linking. This is fine as long as everything is fastened down and there is no mechanical movement as there is no latch.

 

http://www.ledbulbs123.com/images/LED-Strip-lights/Extension-Cable-With-4-Pin-Male-And-Female-Connector-For-LED-Strip-Light-Length-61CM.jpg

 

 

 

I've also seen these quite a lot (this pic is from Sparkfun). There is no standard that I know of....

 

edit to fix annoying removal of all the carriage returns in my post....

 

[J Pearce]

1 - Usually 5050, not found 3528 to be bright enough to compete with stage lighting.

2 - Yhey work. Not a great dimming curve, can cause strobe effects on cameras.

3 - Not the ever popular open frame with no protection on the mains inputs... I have a couple of big 100W PSUs from CPC (can't find them on the website atm though), and some laptop style PSUs for smaller jobs. Constant voltage (cheaper supplies can float high under low load) and sufficient current capacity are the main points to look for.

4 - There's the cheap 4 pin things that come with the tape, or computer molex connectors, or XLR4. The bigger the connector the more vulnerable the pads on the tape are to being ripped off by the weight of the connector.

 

Sticking a big capacitor in parallel with the mains driver can help stability, had a few issues when snapping long runs of LED tape to full, but adding a capacitor for additional smoothing/regulation sorted this.

[bruce]

Any recommended suppliers (ideally UK) for this sort of stuff? Might need one of the basic 4ch drivers (yes, the ten quid ebay ones) by next week, and all of the ebay suppliers (yes, even the supposedly uk-based ones) are obviously shipping from china, with at least 2 week lead time.

[timsabre]

I know the guys at https://www.wholesaleledlights.co.uk/ in Leicester, they are solid suppliers

 

Obviously you will pay more than ebay though.

 

[MarkPAman]

I don't know them, but I've had stuff from them.

 

So +1 from me.

[sunray]

<br />1 - Usually 5050, not found 3528 to be bright enough to compete with stage lighting.<br />2 - Yhey work. Not a great dimming curve, can cause strobe effects on cameras.<br />3 - Not the ever popular open frame with no protection on the mains inputs... I have a couple of big 100W PSUs from CPC (can't find them on the website atm though), and some laptop style PSUs for smaller jobs. Constant voltage (cheaper supplies can float high under low load) and sufficient current capacity are the main points to look for.<br />4 - There's the cheap 4 pin things that come with the tape, or computer molex connectors, or XLR4. The bigger the connector the more vulnerable the pads on the tape are to being ripped off by the weight of the connector.<br /><br />Sticking a big capacitor in parallel with the mains driver can help stability, had a few issues when snapping long runs of LED tape to full, but adding a capacitor for additional smoothing/regulation sorted this.<br />

<br /><br /><br />

 

Are we looking at these things: https://www.ebay.co.uk/itm/DMX512-Decoder-15A-RGB-Controller-LED-Stage-Driver-Mini-Board-3-Channel-Part-Top/263123345513?epid=718793485&hash=item3d435fa069:g:Mr8AAOSwSzdXBwcO:rk:36:pf:0 So far I haven't had any success with the several versions I've tried. I find they have an annoying 'flick' every 5 to 10 seconds. I've found these: https://www.ebay.co.uk/itm/RGB-DMX-512-Decoder-LED-Controller-3-Channel-DC12-24-V-4A/153101544614?epid=27021487571&hash=item23a5902ca6:g:004AAOSwu05bTGGS:rk:31:pf:0 are a bit better after the limiting resister is beefed up but only run on one of my 3 desks. Or am I doing something wrong. These have so far worked perfectly for me but are not addressable; https://www.ebay.co.uk/itm/6A-72W-3-Channel-DMX512-Decoder-Board-LED-DJ-RGB-Stage-Lighting-Driver-Module/272159073559?hash=item3f5df1e517:g:bhgAAOSwxp9W3PqM:rk:2:pf:0

 

<br />1 - Usually 5050, not found 3528 to be bright enough to compete with stage lighting.<br />2 - Yhey work. Not a great dimming curve, can cause strobe effects on cameras.<br />3 - Not the ever popular open frame with no protection on the mains inputs... I have a couple of big 100W PSUs from CPC (can't find them on the website atm though), and some laptop style PSUs for smaller jobs. Constant voltage (cheaper supplies can float high under low load) and sufficient current capacity are the main points to look for.<br />4 - There's the cheap 4 pin things that come with the tape, or computer molex connectors, or XLR4. The bigger the connector the more vulnerable the pads on the tape are to being ripped off by the weight of the connector.<br /><br />Sticking a big capacitor in parallel with the mains driver can help stability, had a few issues when snapping long runs of LED tape to full, but adding a capacitor for additional smoothing/regulation sorted this.<br />

<br /><br /><br />

 

Are we looking at these things: https://www.ebay.co.uk/itm/DMX512-Decoder-15A-RGB-Controller-LED-Stage-Driver-Mini-Board-3-Channel-Part-Top/263123345513?epid=718793485&hash=item3d435fa069:g:Mr8AAOSwSzdXBwcO:rk:36:pf:0 So far I haven't had any success with the several versions I've tried. I find they have an annoying 'flick' every 5 to 10 seconds. I've found these: https://www.ebay.co.uk/itm/RGB-DMX-512-Decoder-LED-Controller-3-Channel-DC12-24-V-4A/153101544614?epid=27021487571&hash=item23a5902ca6:g:004AAOSwu05bTGGS:rk:31:pf:0 are a bit better after the limiting resister is beefed up but only run on one of my 3 desks. Or am I doing something wrong. These have so far worked perfectly for me but are not addressable; https://www.ebay.co.uk/itm/6A-72W-3-Channel-DMX512-Decoder-Board-LED-DJ-RGB-Stage-Lighting-Driver-Module/272159073559?hash=item3f5df1e517:g:bhgAAOSwxp9W3PqM:rk:2:pf:0

[alistermorton]

I've used the 6 channel version of the first controller with no problems, no flickers or flashes so dunno if you're doing something wrong.

[timsabre]

I think we have discussed this before but those controllers flicker if RDM packets are being sent. They do not check for start code zero so any rdm (or other) packet gets output as dimmer levels causing a flick.

[alistermorton]

I certainly wasn't sending RDM so that could make sense.

[J Pearce]

I'm talking about these.

[sunray]

<br />I think we have discussed this before but those controllers flicker if RDM packets are being sent. They do not check for start code zero so any rdm (or other) packet gets output as dimmer levels causing a flick.

No, no RDM in the system. Just desk - Chav colour 50 or Cobra colour control 48 or transcension sdc816 and module, with or without an end resister.

 

<br />I'm talking about <a href='https://www.ebay.co.uk/itm/NJD-NJ971-DMX-Interface-Controller-for-use-RGB-LED-Tape-Light-FFA3600/382355325277' class='bbc_url' title='External link' rel='nofollow external'>these</a>.<br />

 

I have some, they work on my Chav colour 50 but not on Cobra colour control 48 or transcension sdc816. I still find I have an occasional flick, which was fine for the only time I've used them in anger as they were running RGB floods as house lights for a murder mystery set in war time India and we included the flick in the script.

They have a built in buffer amp and terminator so never need an end plug if at the end of the universe, however with a power loss there is no DMX pass through and I've had 2 fail when running on 24V, there is a surface mount resister between the DC supply and the 5V regulator which overheats and fails, I've replaced the resister with a standard 1/4W of a higher resistance.

This is obviously a known problem as the Ebay supplier offered me a 50% refund and explanation of the problem (which is OK at 12V).

[musht]

Pixels can be simpler than RGB to actually use and are advancing fast.

 

APA 102 5V 4 wire seperate clock line, was popular for ability for high refresh rate, it won`t actually sustaing it over any length

 

WS 2812 5V 3 wire, most common pixel currently

 

WS 2813 5V 4 wire, same control as 2812 but with backup data line, one LED failing will just be left isolated

 

WS 2815 12V 4 wire, 12V version! of 2813 , easier power distribution

 

SK 6812 5V 3 wire , 2812 clone, available in White/Warm White and RGBW combos

 

Branded, Meanwell, Puls, TDK Lamda, Power Pax etc PSUs are worth paying for, everytime.

 

JST as illustrated above is common connector, currently liking Weipu SP-13 as a decent IP rated connector.

[timsabre]

Don't forget TM1804 and TM1812 which are 3-wire similar to WS2812 but slightly different.Also LPD8806 4 wire.

 

I am surprised nobody is making a 16-bit dimming version of pixel LEDs. That would be really useful in some of our applications.

 

[musht]

 

I am surprised nobody is making a 16-bit dimming version of pixel LEDs. That would be really useful in some of our applications.

 

UCS 8904 4 channel 16 bit as a chip not a pixel, but appears in no products, just everyones controller will support it.