Recently in Electronics Category

House Power Meter

I've recently installed an 80A Power Meter on the electricity supply to my house. It measures the current active, reactive and apparent power as well as providing a count of the total active and reactive energy. These reading are updated every second.

After installing a 100A isolator and pulling through extra cables, the installation of the power meter was relatively straight forward. It's in an enclosure with an 80A circuit breaker, located inside to avoid inconvenience if it ever trips, and because the distribution board doesn't have enough space for it.

[Closed metal enclosure with electricity supply input/output cables and RS485 cable] [Metal enclosure with lid open showing 80A and 6A circuit breakers and the Power Meter] [Metal enclosure with the cover off showing the circuit breakers and Power Meter] [Electricity distribution board with the live supply out of the 100A isolator going via the Power Meter]

I intend to write an Android app for a real-time view but for now I'm just collecting historical data:

Bar chart of total active energy usage for each day of the month with detailed views of active/reactive power usage and supply voltage

Adafruit Proto Cape Kit for Beagle Bone

I bought one of Adafruit's Proto Cape Kit for my Beagle Bone Black so that I could put 3 relay circuits and pin headers on it. The double-sized PCB is supplied with separate pin headers that you have to solder on yourself.

It provides access to all of the pins but only SYS_5V is provided as a set of power lines and not VDD_5V, so limited current is available. However, this doesn't matter too much given that there is very little space for components.

I had to really squash everything in and use a lot of wires because there was no chance of creating an optimal layout:

3D printed replacement parts

My freezer compartment doors now open and close instead of lifting out thanks to Adrian's 3D printer:

Base layer of printed plastic insert Finished printed plastic insert Comparison of printed and original parts

I've had to glue all but one of them in place as some of the plastic to hold them in has actually broken off the door itself, but they work quite well:

Network Speakers

| 1 Comment

I had an unused Mini-ITX computer which I can make silent (by removing the fan) as long as it isn't doing anything too intensive, and some spare speakers from a broken CD player... so I put together some remote speakers to play music on.

With some cheap bamboo cane and tie wraps I've mounted them at the head of my bed. The server boots over the HomePlug network allowing MPD to connect to it. I'll add a wireless remote control soon.

Speaker frame Speakers at top of bed Remote speaker server

USB powered doorbell

I have a second doorbell because the one in the living room is too far away to hear from the computer - especially with music playing - but it uses up AA batteries far too quickly and I don't easily notice that it's no longer ringing with the main one. So I connected it up to a USB port instead...

[USB powered doorbell]

NTP reference clocks

I've finally finished putting together the parts to connect multiple NTP reference clocks to the same serial port...

[Inside of box]

It uses three reference clocks - one GPS receiver and two radio clocks (DCF77 and MSF).

[MSF receiver]

[DCF77 receiver]

[GPS receiver]

About this Archive

This page is an archive of recent entries in the Electronics category.

Edinburgh is the previous category.

Energy is the next category.

Find recent content on the main index or look in the archives to find all content.

Content authored by myself is just my honest opinion. If you find any words or pictures menacing or offensive, stop reading now.

Jabber

simon@arlott.org.uk
  • Linux
  • Get Firefox!
  • Get Thunderbird!