`DimmableLight::getDetectedFrequency()` returns wrong value on Robodyn AC Dimmer 24A

[mathieucarbou]

• v1.6.0
• Robodyn AC Dimmer 24A
• Inspiration from example: 8_set_frequency_automatically.ino
• Only using ZC pin (control pin is not used)
• France, 50 Hz, 230V
• Board: ESP32 NodeMCU (ESP32-D0WD-V3)

My code:

DimmableLight::setSyncPin(_pin); // ZC pin of Robodyn
DimmableLight::begin();

Calling after, each 5 sec: DimmableLight::getDetectedFrequency()

Returned value is 122.

I have another ZCD module (https://www.pcbway.com/project/shareproject/120_220VAC_Opto_Isolated_Zero_Cross_Detector_Module_for_DIN_Rail_Carrier_Mount_w_57a9f83e.html) and this one works perfectly.

Note: if I set FILTER_INT_PERIOD, getDetectedFrequency () return 0 for both Robodyn and this ZCD module.

[mathieucarbou]

Hello again,

I took some measurements this evening (Owon HDS2202S) and it turns out the Robodyn ZCD pulse is really short in duration: still 5V, but really short, like 0.5 ms, compared to the 1.5 ms duration of the pulse of the dedicated ZCD.

I am wondering if there are some issues detecting that in the code ?

[fabianoriccardi]

Hi Mathieu, which mcu are you using?

[mathieucarbou]

Hi Mathieu, which mcu are you using?

ESP32 NodeMCU devkit

This one: https://www.az-delivery.de/en/products/esp32-developmentboard

I've read the Wiki and learned about some ESP32 issues to detect short pulses, I am trying to activate filters now...

[mathieucarbou]

I added -D FILTER_INT_PERIOD and everything works fine with both the Robodyn and the other ZCD module.

Thanks a lot for this library by the way: far better written than most others, and goes deeper in the details 👍

[fabianoriccardi]

ESP32 NodeMCU devkit

I was supposing it, ESP32 gave quite few troubles, especially when combined with the RobotDyn dimmer. 😅 Glad that you quickly solved it!

Thanks a lot for this library by the way: far better written than most others, and goes deeper in the details 👍

Many thanks!

[mathieucarbou]

... And feel free to use the images above if you need, to illustrate your wiki page or put another ZCD module in ref ;-)

[fabianoriccardi]

That's a good point, in the next days I hope to continue the work with this lib.

[fabianoriccardi]

Add the reference and the images to the wiki page, thanks again!