Shelly box for T&E 3x slots and wago 221 connectors (1Plus, 1L, 2PM, 2.5, Dimmer2)

Part of my series of enclosures designed for Shelly smart devices and Wago 221 connectors.

• Shelly box for T&E 3x slots and wago 221 connectors (this one)
• Shelly box for inline flex wire and wago 221 connectors
• Shelly box for 2x flex wires and wago 221 connectors
• Shelly box for 3x flex wires and wago 221 connectors
• Shelly quad box for 2x devices/5x relays/5x flex wires and wago 221 connectors

Shelly box for T&E 3x slots and wago 221 connectors

This box was designed for wiring light fittings using the UK wiring model (feed/switch/load) on twin&earth wire with wago 221 connectors, but it can be used for other purposes. The box supports Shelly Plus1, 1L, 2.5, 2PM, Dimmer devices.

Electrical safety

• Mains electricity carries danger of death. Please don't attempt to use one of these with real circuits unless you are competent and aware of health and safety procedures.
• Use PETG or other fire resistant materials other than PLA.

Purpose and features

The enclosure is designed to connect 3 twin&earth wires to 1 shelly device using 3 wago 221 connectors. The wires will serve the functions of providing feed power, external switching and a connection to the load.

Shelly device support: Shelly Plus1, Shelly 1L, Shelly 2.5, Shelly 2PM, Shelly Dimmer2

Wire strain relief: Each flex wire entry port has slots for fitting a cable tie as strain relief for the wires.

Attachment holes: The box has counter-sunk holes to attach it to a surface.

Cooling slots: There are cooling slots all around and above/below the shelly device.

Lid fitting: The lid attaches to the box using 4x M3 screws (5-10mm max) which thread into M3 heat inserts to be installed on the box.

Printing notes

• The lid requires supports on the bolt hole counter-bores, otherwise it will not print cleanly (in my case it didn't)

Version control

Version 2.1 - 11/03/2024

• Updated (reduced) cable tie shelf width
• Re-shaped lid to fit (issue in v2.0)

Version 2 was a significant redesign to include the following features:

• M3 heat thread inserts instead of square nut slots or holes for tapping
• Attachment bolt holes on the inside of the box rather than outside brackets
• Cable tie pads inside the box as opposed to accessible from the outside (enables refitting ties without dismounting the box)
• Shelly slot adjusted for compatibility with multiple models