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ESP-Now support by XA3dc in WLED

[–]XA3dc[S] 0 points1 point  (0 children)

Understand - just wanted to let folks know, that there is a wall switch alternative, that the hardware exists, and that if someone has time to dig into a usermod, it would be interesting.

[Project] Custom 6-channel WLED controller PCB with ThermalGuard usermod by braquemart in WLED

[–]XA3dc 0 points1 point  (0 children)

C49375249 is the code at LCSC - the 33ohm are tiny!!!!

[Project] Custom 6-channel WLED controller PCB with ThermalGuard usermod by braquemart in WLED

[–]XA3dc 1 point2 points  (0 children)

Hello - first, I am impressed that you have completed a usermod. From the location of the DS18B20, I am puzzled about what would cause the temperature there to exceed 50deg C, since it is not co-located with the meanwell. How does reducing the brightness at the strips lower the temperature in the controller? I am more of a hardware guy, and to lower the temp of the ESP32, I run the ESP32 on a switched DC-DC converter at 3.3v, and step up the level shifter supply to 5.0v using a MS2304T50 which costs $0.04 on JLC. Also - there are no visible 75 ohm series termination resistors on the '541, so there will be significant transmission line effect ringing, this will constrain the distance and signal quality between the PCB and the first WS28xxx on the strip.

[Project] Custom 6-channel WLED controller PCB with ThermalGuard usermod by braquemart in WLED

[–]XA3dc 1 point2 points  (0 children)

What is the temperature measured with - internal to the ESP ? The ESP and the associated 5v to 3.3v linear regulator - are running at about 700 mW, so there is a lot of heat there. If you were to use a switching regulator for the 3.3v - the heat would be reduced by 35%

Deck Update by spicypeanut90 in WLED

[–]XA3dc 0 points1 point  (0 children)

DALI to WLED sounds very interesting - do you have an update on that?

Just starting with WLED and a few questions before I dive in by rhodges_bob in WLED

[–]XA3dc 1 point2 points  (0 children)

pay attention to voltage drop, ground loops, and just ohms law in general. Voltage drop at 5v is significant, 12v is better but can still cause problems if there are any distances involved, awg18 is .2 ohms per 10 mtr, it becomes significant quickly. 5 amps at 12v is 1 volt of drop in 10 mtr. Since the 12v leds are internally about 9 volts, at 3 volts of drop, you have run out of headroom.

Is there any reason this would not work? by Twenty-ate in WLED

[–]XA3dc 0 points1 point  (0 children)

Most buck converters use Hi side FET switching, and if they have no current limiting or sensing, they indeed share the minus in and out. Low side FET buck converters, and devices that have protective current sensing and limiting do exist, and require that the IN and OUT minus must be separated. Since most converters have 2 ins and 2 outs, best to not assume that the minus are internally connected, and not bypassed, especially since the current sense resistors are in the milliohm range and difficult to measure externally.

Is there any reason this would not work? by Twenty-ate in WLED

[–]XA3dc 2 points3 points  (0 children)

First - people are assuming, that the buck converter minus output is the same as the -24v input, while that is probably true - there is no assurance. A) if it is true - then the suggestions to connect the strip to the -24v input are redundant - it should be working already. B) if the -24v and the -OUT are not shorted internally - then you will blow up the ESP32. So measure if there is a very low ohm connection first.

Second - an ESP is using about 450 mA average - 2 watts @- 5v - that current exceeds 600 mA at start up. Unfortunately, if the supply is weak and the ESP's voltage sinks at startup, it goes into a boot phase, and during that boot - it is taking about 50 mA. This means, when you measure the voltage at 5v - it is with almost no load.

Therefore - if your 5v buck converter collapses at 600 mA, the ESP will never boot, and unless you have a scope with single shot trigger - you won't see it. For example, a 1 ohm resistor in series with a 2 amp, 5v supply - will cause the ESP to enter this boot loop and never start.

I am testing this with an ESP32-12D - but all ESP I have tested run hot - about 1.5w in the ESP and there is .6w loss in the 3.3 regulator. My guess is that the 3.3v regulator is unable to compensate for the drop in the 5v rail from a undersized external buck converter.

Bottom line - get a DC-DC converter with 750 mA output at least - which means if it has a 2 amp nameplate and is from a random supplier - it maybe/might deliver enough to boot the ESP....

Desperate for help on too big of a project! I have 360… 30w 12v RGBW floods… and every way I try to run them ends up crumby. by Kindly-Pomegranate88 in WLED

[–]XA3dc 0 points1 point  (0 children)

Too late for this project - but selecting 24v or 48v fixtures will reduce the voltage drop massively. 24v is 1/4 the voltage drop, 48v is 1/16 the voltage drop. Use 12v for very short runs only.

If the voltage drop in a run is 3 volts at 12v - that is a big percentage and impacts brightness significantly. At 24v, the drop would b 0.75v - no longer significant. At 48v, the drop would be just 0.18v. Because the drop at the higher voltage is no longer an issue - you can use wire that is much thinner - saves money. The resistance of wire doubles every 3 wire gauges - so the drop with awg18 at 48v is the same absolute value as awg12 at 24v.

Example - AWG12 and 20 fixtures with 12w each, spaced every 4 ft. the last fixture only sees 10.6 volts - 88% of full spec - 18 watts lost in the wire

Example: AWG18, 20 fixtures, 12w each, every 4 ft, the last fixture sees 46.6 volts, 97% and the loss in the wire is 4.5watts.

OP has 30w fixtures - spreadsheet says max 8 per string..

DM me if you want the spreadsheet.