21

A well-designed endpoint device will manage loss of mains power. This can be achieved by using a robust filesystem design, or by maintaining sufficient power in battery/supercapacitor supplies to finish any open operations. It is not just a question of maintaining data security, it's about maintaining stable operation over several years of real-time use ...


17

In as much as there is a 'standard' solution I suspect it's going to look like a Wi-Fi enabled microcontroller attached to a relay or MOSFET. Something somewhere has to be on 24/7 if you want round-the-clock control over your outlets. I've made a bunch of internet controlled sockets using ESP8266 ESP-01S modules (not the ESP-01, which has less memory) and ...


15

What is the preferred way to disconnect them from power? What if there is a power cut? I assume you are talking about devices which act as gateways to aggregate and send it to the cloud (for e.g.: Raspberry Pi runs on Debian which is full blown OS) and generally runs from power source which is other than a cell battery. Taking RPi as an example, you can ...


13

You would very rarely want to remotely power off an embedded device. Instead, you put it into sleep mode, otherwise you can never remotely wake it again. In sleep mode, normal functionality is suspended, but you can still remotely wake the device.


10

What is the preferred way to disconnect them from power? What if there is a power cut? Most microcontrollers have a feature called "Brown out detection". This basically a supply voltage monitoring mechanism which keeps the MCU in reset while the supply voltage is below a certain threshold. This threshold is either preset or it can be changed by software. It ...


8

Your smart devices (camera, sensors,...) manage very well power outage by design. For your Rapsberry Pi, you can put an UPS or a powerbank and monitor (ping) your Internet gateway to check if there is a general loss of power and send a SMS with a 3G USB dongle. Even without power outage consideration, you should always and regularly backup your data (...


7

Most smart plugs I have come across are Wi-Fi controlled devices. I expect the regulations would be similar to those imposed on a Wi-Fi router such as Technicolor's TG582n. RTTE Directive 1999/5/EC: Radio and Telecommunications Terminal Equipment. Commission Regulation (EC) No 1275/2008 implementing Directive 2009/105/EC: Ecodesign requirements ...


7

You only need to start involving qualified people for fairly major work. Minor alternations can be done yourself so long as they are done properly. What you are proposing doesn't sound like it would require notification. You can find out more about what is and isn't regulated in the Part P FAQ. Small alternations and general DIY work is specifically ...


6

You've explicitly rejected the factory recommended way to configure the circuit, which is to have only one switch controlling the load, and using remote-only signalling switches for the others. And you're doing this on the supposition that someday one of the switches will fail; but you've only said that it would leave a switch "useless", without saying why ...


5

There is the Sonoff Pow WiFi Switch With Power Consumption Measurement or the SONOFF S31 - COMPACT DESIGN SMART PLUG WITH ENERGY MONITORING that seems to be popular with the DIY community. You can reflash that with new firmware (might not be absolutely needed) and receive mqtt messages on your server. You can then have a TICK Stack to receive and store and ...


5

I would imagine the same restrictions would apply to Smart Plugs and any other electrical device equally; there does not seem to be any specific legislation that applies to IoT devices. The UK Government (which, despite the recent Brexit referendum, still respects EU law as of 2016) has published an extensive guide named Electrical equipment manufacturers: ...


5

The Belkin WeMo sockets can also be controlled remotely from the app. Basically any socket with support for Alexa/Google Assistant will have cloud component to control them (because the smart assistants connect to a cloud end point to do the control). This means you can also use the Alexa/Google Home apps to control them remotely.


5

Some smart plugs can be controlled over the internet without having to be on the same network. D-Link Smart Plugs (http://us.dlink.com/products/connected-home/wi-fi-smart-plug/), for example, have a linked app that allows you to switch the plug on and off from anywhere as well as setting schedules. They can also be connected to things like the IFTTT system ...


4

If you already have a digital meter inline (or can fit a cheap 2nd hand one), then you can optically monitor the 1000 impulse/kwH LED which is likely present (without needing to interface to the optical serial port present on the meter). You can then integrate the impulses to approximate instantaneous power. Bear in mind that you'll need to infer the ...


4

What if there is a power cut? Is my data at risk? For most well designed commercial IoT devices you need not worry about sudden power loss. Let's take case on the Nest Thermostat. The Nest Thermostat uses the Micron 2 Gb NAND flash memory. Given its NAND flash, the file system used must be YAFSS, as YAFFS has been designed specifically for use with NAND ...


3

@Helmar 's comment is quite good for a workaraound : You should monitor power outage. Monitoring power outage is starting to become recurrent here and it is critical to see if there was an intrusion attempt. So several solutions can be managed to detect power recovery: ping your Internet gateway and log the last time you did this. If the time is large (> 1 ...


3

The regulations in the UK cover fixed wiring only, as far as I know. Replacing existing fittings is generally OK, it's only new or specific locations which are regulated. So if it plugs in, it's OK. If it's hard wired, I think it needs to meet the relevant standards.


3

In-line dimmers have to be dimmers rather than switches because they have no neutral return at the switch. This makes any multi-way arrangement nigh impossible. The 'obvious' homebrew solution is a z-wave relay, and a unit to aggregate 'switch' requests into a control toggle. Probably requires an mcu or SBC to facilitate this, and this would extend to more ...


2

Inside the Sonoff, there will be an AC to DC converter like Hi-link HLK-PM03 220V to 3.3V Step-Down Buck Isolated Power Supply Module which is used to power the Wi-Fi module separately. As I have created the same Wi-Fi smart switch using a solid-state relay, ESP-12 generic module and simple LED within an AC-outlet and also created just like sonoff. If the ...


2

Different classes of IoT devices have different requirements as to functioning in light of power loss. Your weather station might not care if power goes down, but your security system might. Your temperature control system might want to function locally despite power loss. As to how to control your device there should be a control channel that allows ...


2

Yes, the Linky power meters are able to count both power received from the grid ("puissance soutirée" in French) and power injected back to the grid ("puissance injectée"). This document from Enedis (the electricity distribution network that installs those meters) says: Linky permet l’enregistrement de 2 courbes de charge, l'une en injection et l'...


2

I would use a current transformer. A current transformer is typically a toroidal magnetic core through which one power wire is threaded, with a few hundreds turns wrapped around the core. A current transformer causes the current in the secondary to be equal to one over the turns ratio times the current in the primary. If there are 500 turns on the ...


2

If you have internet, it would be easiest to use a switch that can be controlled via IFTTT. Just google IFTTT light switch and you'll see the light ! If you dont have internet, you can still use a RaspberryPI with a relay shield and run an MQTT broker on a PC to which the raspberryPI will connect. And you can then run another MQTT program on the PC to send ...


1

One possibility would be a Shelly Button with a Shelly 1 inside. It can use its own firmware or be flashed by something like ESPHome (both are supported in Home Assistant) The setup is not cheap, though (~12€ piece)


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