Building the Energy Meter is quite straightforward but make sure that you refer to our warning panel. This is not a project for the inexperienced!

As shown in the photos, all the parts are mounted on two PC boards: (1) a main PC board coded 04107041 (138 x 116mm); and (2) a display PC board coded 04107042 (132 x 71mm) for the LCD module and switches.

Fig.8: follow this layout to install the parts on the display PC board. The Altronics LCD module goes in the red position, the DSE module in the blue position and the Jaycar module in the green position.

Note that the display board was designed to accept three different LCD modules – from Altronics, Dick Smith Electronics and Jaycar. The straight-line 14-pin connection caters for the Altronics and DSE LCD modules, while the dual 7-way connection is for the Jaycar module.

Altronics, Dick Smith Electronics and Jaycar will all have kits for this project, so obtaining a kit will be easy. Note, however, that Dick Smith Electronics will be supplying a different case to the one used for our prototype. They’ve also altered the PC board layouts slightly, to get everything to fit inside their case. Their kit department built a fully-working prototype to confirm the design (see photo) and full instructions will be supplied with the kit.

Begin by checking the PC boards for the correct hole sizes. The LCD module and transformer require 3mm mounting holes, while the switches require 6.5mm holes. In addition, 2mm holes are required for the mains wire connections.

Check also that there are no breaks in the copper tracks or shorts between any of the tracks or pads. Note, however, that one of the tracks on the main board has no connection at one end (ie, near the 10Ω resistor, to the right of the transformer). This is correct – this track simply functions as an earth guard, so don’t join it to anything.