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S Jun 27, 2021 at 3:53 vote accept RockWest
S Jun 27, 2021 at 3:53 vote accept RockWest
S Jun 27, 2021 at 3:53
Jun 27, 2021 at 3:53 vote accept RockWest
S Jun 27, 2021 at 3:53
Jun 26, 2021 at 0:28 answer added Seamus timeline score: 1
Jun 25, 2021 at 23:06 answer added Milliways timeline score: 0
Jun 25, 2021 at 17:05 comment added RockWest I appreciate your words of caution @Milliways with respect to the guides I linked. I did use them as a guide and have something similar wired up now. There are some differences in my implementation, specifically it's much lower amperage and my connections are soldered and insulated more rigorously. However you warning is ominous, and I wonder what I am missing, could you elaborate on your concerns? What additional details can I provide to help?
Jun 24, 2021 at 18:53 comment added Seamus @Dougie: Oh sorry - the voltage level wasn't the basis of my comment. You're talking "optocoupler" & OP is talking about LEDs and photodetector. Check his comment...
Jun 24, 2021 at 11:28 comment added Milliways @Dougie 50V is Low Voltage (same as 110 or 220V) - according to IEC and most national codes (admittedly at the low end) not that this has much to do with the problem.
Jun 24, 2021 at 7:09 comment added Dougie @Seamus 50V is SELV level so using it to light an LED isn't outside any wiring codes. It's not something I'd do with 110V or 220V, for that I'd use an current clamp CT.
Jun 24, 2021 at 5:11 comment added tlfong01 Ah, the popular toy for EE newbies are ninjas alike is ACS712: (1) ACS712: Fully Integrated, Hall-Effect-Based Linear Current Sensor IC with 2.1 kVRMS Voltage Isolation and a Low-Resistance Current Conductor - Allegro: allegromicro.com/-/media/files/datasheets/acs712-datasheet.ashx, (2) Rpi Current Sensing Using ACS712 and INA219 - Rpi SE, Asked 2019feb20, Viewed 7k times: raspberrypi.stackexchange.com/questions/94403/…. Cheers.
Jun 24, 2021 at 0:35 comment added Milliways Incidentally just out of curiosity I looked at the instructables link you followed. I am appalled! DO NOT do this! This violates so many electrical principles and safety rules.
Jun 23, 2021 at 23:17 review Close votes
Jul 12, 2021 at 3:06
Jun 23, 2021 at 23:00 comment added Milliways As you suggest this is not a Pi problem but an EE question. I am an EE but given the sparsity of details I would be reluctant to suggest a solution, although I would likely use an opto isolator but running from AC is not straight forward.
Jun 23, 2021 at 22:18 comment added RockWest That's exactly what I needed, thanks @Dougie. Works like a charm. For future reference, I used the following guides: instructables.com/LED-on-AC-Mains peppe8o.com/…
Jun 23, 2021 at 20:32 comment added Dougie Your 50V AC should be OK to light the LED in an optocoupler (on half of the AC cycle if you don't rectify it to DC). An optocoupler can be used to switch a GPIO.
Jun 23, 2021 at 18:50 review First posts
Jun 23, 2021 at 20:32
Jun 23, 2021 at 18:49 history asked RockWest CC BY-SA 4.0