SDM Series

SDM Series — Compact Energy Meters with Clamp CTs

Future-ready smart energy meters with split-core clamp CTs, designed for DIN rail installation. Supports three-phase, split-phase, and multi-branch single-phase monitoring — engineered for both IEC and UL markets.

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Product Variants

SDM products are defined across three dimensions:

1. Product Platform

	SDM01 Combo	SDM02 SP
Target System	Three-phase (3P4W) or multi-branch single-phase	Split-phase / two-phase
Market	IEC (EU, Asia, etc.)	IEC + UL (North America)
Rated Voltage	220–240 VAC (L-N) / 380–415 VAC (L-L)	110–240 VAC (L-N) / 220–240 VAC (L-L)
No. of CTs	3× split-core CTs	2× split-core CTs
Dimension	113.7 × 18.0 × 65.9 mm (1MW DIN rail)	42.2 × 41.6 × 20 mm
Wired Communication	RS485 (Modbus RTU)	—
Active Energy Accuracy	Class 1 (IEC 61557-12)	Class 1 (IEC 61557-12)

2. CT Current Rating

CT Rating	Aperture	SDM01 Combo	SDM02 SP
120A	Ø16 mm	✅	✅
200A	Ø20 mm	✅	✅
100A (UL2808)	Ø12 mm	—	✅ (North America)

💡 The CT is factory-calibrated together with the main module. Always order the CT rating that matches your installation — CTs are not interchangeable between ratings.

ℹ️ Current monitoring can be extended up to 400A via custom CT configurations. Please contact us for customization inquiries.

3. Connectivity

Wireless — select one firmware variant per order:

Variant	Communication	Archetecture	API Style	Typical Users
Tuya Wi-Fi (*TW)	Wi-Fi	BK7231N SoC (Tuya Firmware, Slave) + Metering MCU (Bituo Firmware, Master)	MQTT(Tuya Proprietary)	Tuya ecosystem, IoT beginners
Tuya Zigbee (*TZ)	Zigbee	EFR32MG21 SoC (Tuya Firmware, Slave) + Metering MCU (Bituo Firmware, Master)	Tuya Proprietary Clusters	Tuya ecosystem with Zigbee hub
Open Wi-Fi (*EW)	BLE + Wi-Fi	ESP8685 SoC (Bituo Firmware, Master) + Metering MCU (Bituo Firmware, Slave)	MQTT, HTTP, UDP, BLE	DIYers, System Integrators
Std. Zigbee (*TZ-U01)	Zigbee 3.0	EFR32MG21 SoC (Bituo Firmware, Master) + Metering MCU (Bituo Firmware, Slave)	Standard Zigbee 3.0 Clusters	System Integrators, DIYers

Wired — availability by platform:

	SDM01 Combo	SDM02 SP
RS485 (Modbus RTU)	✅ Included in all variants	—

ℹ️ On SDM01 Combo, RS485 is always present alongside the wireless module — it is not a separate variant choice.

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Sub Pages

Model	Description
SDM01 Combo	3PN / Multi-branch 1P, 120A or 200A
SDM02 SP	Split-phase / 2×1P+N, 120A / 200A / 100A (UL)

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Related

SPM/SDM Zigbee Cluster Reference

SDM01 Modbus RTU Map