
Device identification
- Device name: CT 120A
- Manufacturer model: CT313
Short description
CT 120A (The Device) is a split-core current transformer for the Shelly Pro 3EM energy meter.
Features
- Snap-on, screwless mounting system
Connector to Shelly Pro 3EM
- 2-pin MX3.0-2x1Y connector
Safety features
- Secondary winding high voltage protection
Specifications
| Type | Value |
|---|---|
| Physical | |
| Size (H×W×D): | 45×40×36 ±0.5 mm / 1.77×1.57×1.42 ±0.02 in (without the cable) |
| Weight: | 75 ±1 g / 2.65 ±0.05 oz (with the cable) |
| Conductor aperture: | Ø15 mm / Ø0.6 in |
| Core: | Ferite |
| Shell material: | Plastic |
| Color: | White |
| Environmental | |
| Ambient temperature: | -10 °C to 50 °C / 14 °F to 122 °F |
| Humidity: | 0 % to 80 % RH |
| Max. altitude: | 2000 m / 6562 ft |
| Electrical | |
| Primary/secondary current ratio: | 3000/1 |
| Rated max. primary current: | 120 A |
| Electrical strength: | 3000 VAC, 60 sec |
Installation

Legend
| Label | Description |
|---|---|
| A | Shelly CT 120A |
| B | Cable tie (another one on the opposite side) |
| C | Primary conductor |
Compliance
- Declaration of conformity