HELP! Rail Lights not working

SuperLongBoard 📖Docs
1

Hello,
I am trying to get my LED Rail lighting to work on my Longmill MK2.5 48X30 with the latest B5.0.5 firmware flashed to the SLB. The light I am using are BTF-Lighting WS2811. These are 12V individually addressable LED’s with NO controller and 60 LED’s/meter.

I am using 55" of lights which works out to about 83 LED’s.

I am also using an External power supply (12V, 10A) and it is plugged into the LED PWR port on the SLB (made certain polarity was correct).

The lights are wired to an XH 2.54mm female pin header that is plugged into the RAIL plug on the SLB. Again, assured that polarity was correct per silkscreen on SLB.

I have verified 12.49VDC between V+ and GRD and 0VDC on the CTL pin.

In the gSender Firmware section, I have set $665 to 84 (83 LED’s on strip, plus 1 on SLB). Saved settings and cycled power on the SLB. Still cannot get the lights to come on. What am I doing wrong? Any help is greatly appreciated! Info below.

  1. Firmware version: B5.0.5
  2. Sender: gSender 1.4.8
  3. Relevant tested files: N/A
  4. Any pictures or videos attached showing the issue: N/A
  5. Upload of the ‘Diagnostics’ PDF file: New users not allowed to upload! WTH?
2

I had no luck doing it that way. Think the current draw is to high through the slb switch.
I bought an external 24v relay & switched the 12v through it. Connected the relay coil to one of the slb switched 24vdc outputs & wrote 2 macros using M codes (64/65?? I’m not at machine) to switch on & off. I also recoded one of the buttons on the panic button box to turn the light’s on.

3

Appreciate your response! That is a disappointment for sure! I will see what relays I have lying around. If I happen to have a 12VDC coil on one, I will try that first, otherwise, I guess I can take a page out of your book and use the External Power and a 24VDC Coil Relay.

4

Hey Jaybird,

Are you in the position to cut the minimal cuttable length of the strip and play around with that to see if you can light it up via the slb?

At this point the solder iron has to be heated. why not see if you can mitigate the problem by reducing the amount of leds. 3A isn’t much to work with at 12V.

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5

Hi @JayBirde, the components on the board to control externally addressed LEDs are only designed to handle up to 3A so that might be the issue you’re running into. Unfortunately it just would add extra cost for more processing and power bandwidth to handle much longer LED strips and to be honest I wasn’t sure how many people would be hoping to run long RGB strips of their CNCs. It looks like your LEDs consume about 0.3W/LED when white which at 12V should be 0.025A/LED and a total of only 2.1A needed, even if you add in a buffer so that has me wondering if perhaps there’s some other issue going on. I know we’ve done lots of testing on typical 5V Neopixel-style LEDs but perhaps yours are using another chip that our firmware hasn’t been tested for

What @Rusty_golfer mentioned, if you did that then it’s another option but you’d only be able to do on/off control and not have the board do the colour control - for people that just want white on/off then it’s perfectly reasonable

6

You might be able to feed the led power with a 24V power supply and step it down at the led output to 12V to halve the amperage the SLB has to handle, but that will only work if the problem is indeed that your strip is drawing too much amps.

7

Don’t really want to cut the LED strip, as I have mounted an aluminum channel under the X gantry and the LED tape is mounted to that with a diffuser over it. It would be a royal pain to try and get that strip off the channel! I will probably just use a 12VDC coil on a SPST relay and re-route the external power to the appropriate spot on the SLB. I relished the idea of hooking these lights up on the given ports, but there isn’t a lot of options the way the board is currently made. Maybe the next revision could include a relay on the board capable of switching a bit of power. Thanks for the reply though. Appreciate it!

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8

Hi @JayBirde, just want to let you know that I ordered the same strip you’ve got because I vaguely recall someone else mentioning this same issue and thought I’d give it a shot.

I got some wiring done today and started playing around. Things definitely seem not 100%, but I’ll need more time to play around to figure out what the reason is. I’ll have to revisit next week and let you know once I find more :+1:

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9

So “next week” later, I’ve confirmed my original suspicion and now the docs are in the process of being updated accordingly. Basically the manual has now been revised to mention that “only 5V RGB LED strips are able to be supported by the SLB” and this is for two reasons:

  1. Different voltage LED strips actually tend to use different chips / communication protocols, which means that if the SLB were to support different strips we’d have to configure a way for someone to select their LED type which would add to the setup complexity
  2. The ‘Rail’ output plug needs to have an extra mosfet added to support the wider range of strip voltages

I want to apologize since I know original docs specified that strips 5-24V could be used, so if anyone felt misled they can contact me and I can arrange to send you a 5V strip as a replacement for your setup. If anyone else has any questions feel free to let me know or open up a new topic

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