3 ms·

Is there anything simpler/cheaper that can go into a wall socket and be queried over bluetooth? (or join an existing wifi network)

by 1996 6y ago

irq 6y ago
All you can measure by plugging into a wall socket is (1) voltage; (2) power, but only for devices plugged into that outlet (by installing a meter like a kill-a-watt between the outlet and the device). In order to determine power consumption for an entire circuit, or your entire house, you need to put a sensor around a wire in the breaker box. You can’t even do it in the walls because once power cabling leaves your breaker box, all the conductors for a given circuit are bundled, and if you put a current transformer around that bundle, it will show net zero power because it’s summing both halves of the AC wave. You need to get a sensor around just the hot wire of the circuit, which is only accessible on its own inside the breaker box.
KingMachiavelli 6y ago
There are a lot* of cheap 2.4Ghz wireless outlets that can be flashed with custom firmware that supports power usage & outlet control over MQTT & other protocols. Keep in mind that these devices have to be manually configured & calibrated. https://github.com/arendst/tasmota/ https://github.com/arendst/tasmota/ * Some new versions of these outlets come with firmware that can not be patched/flashed so do some research. Also most of these are limited to 10 amps of restive load... inductive loads like motors, compressors, and to an extent power supplies, will have peak loads 3-4x there 'real' consumption which can damage the relay if its not rated for the high initial load. If anyone knows of a cheap alternative or cheap DIY that can handle +20A I would be very interested as it would be nice to be able to control things like fridges without worrying the outlet will fail closed & my food will spoil.

3 ms·

Is there anything simpler/cheaper that can go into a wall socket and be queried over bluetooth? (or join an existing wifi network)

by 1996 6y ago

Is there anything simpler/cheaper that can go into a wall socket and be queried over bluetooth? (or join an existing wifi network)

irq 6y ago
All you can measure by plugging into a wall socket is (1) voltage; (2) power, but only for devices plugged into that outlet (by installing a meter like a kill-a-watt between the outlet and the device). In order to determine power consumption for an entire circuit, or your entire house, you need to put a sensor around a wire in the breaker box. You can’t even do it in the walls because once power cabling leaves your breaker box, all the conductors for a given circuit are bundled, and if you put a current transformer around that bundle, it will show net zero power because it’s summing both halves of the AC wave. You need to get a sensor around just the hot wire of the circuit, which is only accessible on its own inside the breaker box.
KingMachiavelli 6y ago
There are a lot* of cheap 2.4Ghz wireless outlets that can be flashed with custom firmware that supports power usage & outlet control over MQTT & other protocols. Keep in mind that these devices have to be manually configured & calibrated. https://github.com/arendst/tasmota/ https://github.com/arendst/tasmota/ * Some new versions of these outlets come with firmware that can not be patched/flashed so do some research. Also most of these are limited to 10 amps of restive load... inductive loads like motors, compressors, and to an extent power supplies, will have peak loads 3-4x there 'real' consumption which can damage the relay if its not rated for the high initial load. If anyone knows of a cheap alternative or cheap DIY that can handle +20A I would be very interested as it would be nice to be able to control things like fridges without worrying the outlet will fail closed & my food will spoil.