I wanted to make a number of electro-modules re-using fischertechnik 60x60mm cassettes and adding various (cheap) electronic components to measure voltage, current, temperature, time as well as timers, thermostats and chargers. It needed a customised lid for the cassette.

This was achieved through a remix of the excellent design by Dan Malec using his fischertechnik 6060 cassette lid design (https://www.thingiverse.com/thing:4544287) as a base and adding:

1. text to the panel - module panel_text - remixed from Heartman (https://www.thingiverse.com/thing:1264391)

2. modifications to use standard tubes (“bundhulse”) as connectors (https://www.fischerfriendswoman.de/index.php?p=7&sp=3#R7145)

3. option to add holes for toggle switches for some of the meters

4. various designs for different lids for various electronic applications/components that can be ordered from various on-line suppliers:

A: VA-meter - search for "digital panel volt amp meter" B: Solar Charger C: Counter - one box - search for "Voltcraft DCM220W" D: Counter - two boxes - search for "digital teller 4 digit" E: Timer - search for "mini dual display time relay" F: Thermometer - search for "Voltcraft TM-70" G: Thermostat - search for "12V digital panel thermostat" H: Relais: Model 1 - uses 5V high 2-channel relay - DIL16 I: Relais: Model 2 - uses 5V low 2-channel bi-stable relay - DIL16 J: Relais: Model 3 - uses 2x 5V low 2-channel bi-stable relay - DIL16 K: Relais: Model 4 - uses 2x 5V high 2-channel relay - DIL16

All these units are intended for use with fischertechnik and take 5-9V DC. Color was used to identify function where possible and construction was simple. The connection tubes are inserted and fixed with a small hammer, strengthened with epoxy or a glue-gun. The rest of the connections are soldered. The latter has to happen with some care as the panels soften quickly. In some of the modules protective diodes are placed to protect the unit against reverse voltage. The timer, thermostat and solar chargers have DC/DC step-up converters.

Fischertechnik has produced several types of relay, but these have the disadvantage that they are mono-stable. The relays in model 2 and 3 are of the bi-stable type which have the advantage of not drawing current in either state but only for the switch.

The foto’s and SCAD files provide additional information.