SDM01 G2X

Status: Preliminary | Applies to: SDM01G2X | Hardware Revision: V1.0+ | Last Updated: 2026-07-28

1. Introduction

The SDM01 G2X is an ultra-slim 18mm energy meter for precise three-phase or multiple single-phase monitoring. It delivers high-speed reporting for dynamic load balancing and export limiting, alongside an external antenna for reliable connectivity.

Product Highlights

Bi-directional Power Tracking: Delivers high-precision bi-directional monitoring for both imported energy and exported power generation.
Minimalist 1MW Design: Effortlessly fits into space-constrained distribution boxes, utilizing snap-on split-core CTs for rapid, non-intrusive installation.
Real-Time Monitoring: Provides continuous, live tracking of critical electrical metrics, including voltage, current, and active power.
Local WiFi API for HEMS: The dedicated WiFi variant features robust local APIs, seamlessly driving dynamic load balancing (DLB) and export limitation.
Long-Range LoRaWAN Integration: The LoRaWAN variant ensures reliable, long-distance data transmission, making it the ideal choice for large-scale building and infrastructure monitoring.

Typical Application

Home energy management systems (HEMS)
energy management systems (EMS) for small business
Energy management systems (EMS) for buildings, Infrastructure, and Industry
Dynamic load balancing (DLB) for electrical vehicle charging
Export limitation for renewable power generation

2. Part Description

Connector for voltage take-offs connection

The monitor is powered by AC power supply and measures voltage through four cables: X, Y, Z, and N

Connector for current transformer connection

The Red (+) and Black (-) wires of CT(X), CT(Y), and CT(Z) must match the corresponding polarity of the connector.

External Antenna Connector

For Wireless communication

Reset button

Press and hold for 3–5 seconds to enter pairing mode.

Status LED (ACT)

Indicates device operation and network status through different flashing patterns.

Alarm LED (AL)

Flashes to indicate system alarms or errors.

Product Model

Main unit product model

Locking clip for DIN rail mounting

Mounts onto a 35mm DIN rail.

Split-core CT locking clasp

Ensure the clasp is securely locked for precise measurement.

Positive power flow direction

Indicates positive power flow direction for CT(L1), CT(L1), and CT(L3) installation.

3. Technical Data

Rated voltage (Input)

~220-240 VAC phase to neutral, 50/60 Hz ~380-415 VAC phase to phase, 50/60 Hz¹⁾

Max monitoring current I_max

50A / 120A / 300A / 400A

Over-voltage category

III

Rated insolating voltage U_i

440V

Rated impulse withstand voltage Uimp

4kV

Pollution degree

Power Supply

100~240 VAC (L1-N)

Protection degree

IP20

Energy measurement accuracy

Class 1 (IEC 61557-12)

Maximum Power consumption

≤ 2VA

Rated operating temperature

-25℃ to 55℃

Main module dimension

113.7×18.0×65.9mm

Clamp CT apertures

Ø10 / Ø16 / Ø24 / Ø36 mm

Communication Type

BLE+Wi-Fi; BLE+LoRaWAN

Remark: 1) Not suitable for 3P3W installation.

4. Mechanical Outline

Dimension: Unit in mm
Main Unit: Monitoring module for DIN-rail installation (18mm width)

Split-core Current Transformer - 50A (CT Clamp - 50A):

Split-core Current Transformer - 120A (CT Clamp - 120A):

Split-core Current Transformer - 300A (CT Clamp - 300A):

Split-core Current Transformer - 400A (CT Clamp - 400A):

5. Electrical Installation

Wiring Diagram

⚠️ Safety Remarks:

The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
The device must be installed, operated, serviced, and maintained ONLY by qualified professionals.
Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

Three-phase (3P4W) System Wiring

Single-phase System Wiring up to 3 Branch Circuits

Note:

Voltage measurement must match current measurement – V₁ (I₁) ; V₂ (I₂) ; V₃ (I₃) , to measure electrical data correctly.
It can cause product damage, if the blue cable for N connection is connected to phase conductors by mistake

Installation Video

🚧Coming soon...

6. User Interface

Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

LED Indicator

Solid ON

Device connected - the device is online and functioning normally with cloud connectivity.

Flashing at 2Hz

Pairing mode – press and hold the reset button until the LED flashes rapidly.

Flashing at 0.5Hz

Reconnecting to network - the device is attempting to reconnect using saved network settings.

Flashing at 1Hz

Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.

Flashing at 0.25Hz

The device failed internal self-check. Please power off, restart, and reconfigure the network settings.

Flashing at 1Hz

Alarm reminder - The device has detected a fault. Please check the wiring and power supply.

Solid ON

Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.

Flashing at 2Hz

Pairing mode – press and hold the reset button until the LED flashes rapidly.

Flashing at 0.5Hz

Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.

Flashing at 1Hz

BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.

Flashing at 0.25Hz

The device failed internal self-check. Please power off, restart, and reconfigure the network settings.

Flashing at 1Hz

Alarm reminder - The device has detected a fault. Please check the wiring and power supply.

7. System Integration

Wireless communication

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

Note:

Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.

The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

Zero-Configuration Discovery Mechanism (LAN Addressing)
- mDNS / DNS-SD: Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
BLE Near-Field Communication Mode (Offline/Maintenance)
- BLE GATT (Time-limited activation): Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
- BLE Broadcast (Always-on 24/7): Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
LAN Standard Mode (Ultra-low Latency Device Communication) Plaintext or lightweight encryption for local networks.
- Modbus TCP: Used for local linkage with EV chargers and PV inverters.
- Local MQTT: Used for local integration with open-source smart home ecosystems.
- WebSocket (WS) / Raw UDP: Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
- HTTP / CoAP: Suitable for low-frequency parameter configuration and status queries.
Cloud Device Access Layer (Device-to-Cloud / Southbound API)
- MQTTS (MQTT over TLS 1.2/1.3): Core main communication link.
- HTTPS (OTA dedicated): Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.

8. Ordering Information

Ordering number

Description

SDM01G2X-TW-12

SDM01G2X SCTA-3×120A/Φ16 Wi-Fi (Tuya LAN+)

SDM01G2X-TW-20

SDM01G2X SCTA-3×200A/Φ20 Wi-Fi (Tuya LAN+)

SDM01G2X-TW-30

SDM01G2X SCTA-3×300A/Φ16 Wi-Fi (Tuya LAN+)

SDM01G2X-TW-40

SDM01G2X SCTA-3×400A/Φ20 Wi-Fi (Tuya LAN+)

1) Tuya LAN+: Tuya LAN+ is a specific Wi-Fi SoC firmware provided by Tuya Smart that features local area network (LAN) communication. It is suitable for local LAN communication with products such as EV chargers, microinverters, and micro-energy storage systems that are also equipped with Tuya LAN+ communication firmware. This model can only be purchased through Tuya's official or designated channels.

Ordering number

Description

SDM01G2X-EW-12

SDM01G2X SCTA-3×120A/Φ16 Open Wi-Fi

SDM01G2X-EW-20

SDM01G2X SCTA-3×200A/Φ20 Open Wi-Fi

SDM01G2X-EW-30

SDM01G2X SCTA-3×300A/Φ16 Open Wi-Fi

SDM01G2X-EW-40

SDM01G2X SCTA-3×400A/Φ20 Open Wi-Fi