ESP8266 NodeMCU Photoresistor with MQTT question

Tags: #<Tag:0x00007f77fb0d0758> #<Tag:0x00007f77fb0d0668>

I am trying to to monitor my dryer’s led light with a NodeMCU board. My dryer is electric and uses 240 volt connector so I can’t monitor it with a smart plug at that voltage. I saw 1 user who was using this on reddit in this post but he seems to have gone inactive

Does anyone have any resources they can point me to or advice? I have spent hours trying to find a project I can use but they all seem to be dead ends. I already monitor my washer and while its nice I really need to know when to get the clothes out of the dryer before they are wrinkled.

What about this with Tasmota or Esphome firmware? It is genial simple idea.

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Thanks! I’ll see if I can get this working. This would be my first ESP project to try and getting started due to lack of direction seems to be the biggest challenge right now.

Why not? There are plenty of 220/240v smart plugs with monitoring.

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Hmm maybe I am looking on the wrong places? I’m in the U.S. So our normal plugs are 120 and the only 240 plug I saw was an Aeotech one on Amazon with a lot of pics of it melting.

Do you have any recommendations?

Oh I see, didn’t realise you were in the US. How do you get 240v to your appliance then?

Large appliances (electric dryers, electric stoves, and electric heaters mainly) have 240 runs to them and if it plugs in, as supposed to direct wiring, it has a large plug that’s different from standard plugs.


I bet nobody ever wishes that the US had gone with the rest of the world and used 240v from the outset :slight_smile:

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I have just looked at how 240v works in the US

I think I would stick to the approach you are using.

Also you can use an accelerometer or a vibration sensor to work out when a dryer or washing machine is going.

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I was going to suggest power monitoring, but yeah where we live dryer circuits are 220Vac/30A… not many plugnplay devices that can monitor that, and they are all screw terminal type. At least you’d have to cut into some 10awg and wire it in.

Another though is use an inductive pickup on the wire… would be cleaner than a photocell and wires taped on front.

I work on 110 and 220 all the time. Most electrocution injuries here come from 110/15A or 20A. If we didnt have 110, a lot of those injuries might become deaths.

220 is more efficient, but also if you look at it it is the same 220 all over the us… we just have it split in 2 phases to get 110 lines out of it (hence the neutral lines). So the 110 is only the last 100ft or so of copper. I’m fine with that considering the safety it brings. I would say the same about ground wiring… US has a better infrastructure in this regard. Unlike English vs metric, it is an asset for us, not a liability lol (though some might say there are benefits to us using English bolts in the long run).

I’ll see if I can google up a set up like that. I am not really sure what to search yet. I’m kinda outta my wheel house trying to fill a need on this one sadly.

I would probably do this with a clamp on inductive coil, a hall AC current sensor, and esphome on a wemos d1. Here is a tutorial that should give some ideas and specs (it is for some random uC, and resistors instead of a hall sensor, but the basic idea is the same). Since you don’t need accuracy to tell how much $energy is used, the resistor approach should be good enough.

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It looks like the link didn’t make it/got removed?

Indeed it is gone… here goes another

In case… //

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