tlfong01 wrote: ↑
Thu Jul 12, 2018 7:08 am
I gave up and will try another new toy, a mini water pump.
My water pump is on its way. I have nothing interesting to do before it arrives, so I googled around to see what other hobbyists are playing with their AC220V relay toys.
I found the following yesterday question interesting.
Relay connected to rpi zero w - causes to freeze - by guyd 2018-ju7l11
The original poster is using Rpi and relay to control an AC220V windows shade motor but his Rpi freezes after a number of successful relay switching. I have seen similar reported problems while googling last month, usually Rpi freezes, or becomes crazy, or one water pump unexpectedly and randomly triggers another water pump etc. Similar to the Rpi KY019 relay newbies, all
such questions have no confirmed acceptable answers, therefore all those disappointed newbies disappeared after a while, and I guess are still weeping in the dark, ...
My wild guess is that EMI
(Electromagnetic Interference) causes all trouble. But I have zero experience in EMI, so perhaps I can do some experiments on that, to find what is going on, ...
I remember I have a Rpi Zero W lying in my no-time-to-play-toys box, collecting dust for a year or so. Perhaps I should dedicate this lonely RpiZeroW to control my coming water pump to verify my guess that EMI is the problem.
> Rpi Zero W collecting dust for a year or so, ...
Actually I bought my RpiZero W from Argon40 in 2018dec, for HK$117.75 (= USD15). In other words, my RpiZW is only 7 months ago. I remember I bought it because I hope to play with the Google Visual Bounty. But later I found the Google AIY with the Visual Processing Unit (Intel Movidius MA2450 ) is not that powerful, and that the Rpi onboard GPU is not supported (On the other hand my Windows 10 PC's much more powerful Nvidia GPU is supported by the Google AI software) . The Google vision software for Visual Bonnet at that time seemed buggy. So I was disappointed and threw my Zero W into the junk components box collecting dust.
And BTW, an Rpi's authorized distributor in China
https://703805.world.taobao.com/index. ... 689295IRpl
is now selling Rpi ZW for also around USD15 (RMB105).
https://item.taobao.com/item.htm?id=55 ... acQAvD_BwE
That shop is even selling the Movidius Stick, and Intel TX2 development board, with 6 core CPU, 8GB 128bit, 32GB eMMC, Nvidia Pascal 256 Cuda cores, .... The low tech, hopelessly lagging behind Hongkong hobbyists are indeed losing face!
Anyway, next time perhaps I could get my second RpiZW from them, together with other Rpi goodies, with a much cheaper express deliver fee, ...