---
title: Shelly Pro 3EM Switch Add-on
date: 2025-11-05T05:46:15Z
modified: 2026-06-08T09:35:39Z
permalink: "https://tech.co.za/product/shelly-pro-3em-switch-add-on/"
type: product
status: publish
excerpt: Shelly Pro 3EM Switch Add-On Extends The Possibilities Of The Shelly Pro 3EM
wpid: 557523
product_brand:
  - Shelly
product_type:
  - simple
product_cat:
  - Smart Home
featured_image: "https://tech.co.za/wp-content/uploads/2025/11/SHELLY-PRO-3EM-SWITCH-ADD-ONa.png"
---

### Diagrams

**WIRING**

### Resistive load

![](https://shellysa.co.za/wp-content/uploads/2024/09/Pro-Switch-Add-on-wiring-115x300.png)

### Inductive load and RC snubber

![](https://shellysa.co.za/wp-content/uploads/2024/09/Pro-Switch-Add-on-wiring-RC-snubber-167x300.png)

**LEGEND**

![](https://shellysa.co.za/wp-content/uploads/2024/09/Pro-Switch-Add-on-wiring-legend.png)

### SPECIFICATIONS



| Physical |  |
| --- | --- |
| Size (HxWxD): | 94x19x69 ±0.5 mm / 3.70×0.75×2.71 ±0.02 in |
| Weight: | 20 ±1 g / 0.70 ±0.05 oz |
| Mounting: | DIN rail, attached to a Shelly Pro 3EM |
| Screw terminals max torque: | 0.4 Nm / 4.43 lbin |
| Conductor cross section: | 0.5 to 2.5 mm² / 20 to 14 AWG (solid, stranded and bootlace lugs) |
| Conductor stripped length: | 6 to 7 mm / 0.24 to 0.28 in |
| Shell material: | Plastic |
| Color: | White |
| Environmental |  |
| Ambient temperature: | -20 °C to 40 °C / -5 °F to 105 °F |
| Humidity: | 30 % to 70 % RH |
| Max. altitude: | 2000 m / 6562 ft |
| Electrical |  |
| Power supply voltage AC: | N/A |
| Power supply voltage DC: | 3.3 V and 12 V (from Shelly Pro 3EM device) |
| Power consumption: | < 1 W |
| Output circuits ratings |  |
| Max switching voltage AC: | 240 V |
| Max switching voltage DC: | 30V |
| Max switching current AC: | 2A |
| Max switching current DC: | 2A |