Description
Electric Multi-turn Actuator Overview
Bonray’s BD/BDM20-C8 intelligent multi-turn actuator delivers precise valve control in industrial environments. It combines advanced electronics with rugged mechanics, serving applications from water treatment to oil refining. A dot-matrix LCD shows torque, position, and alarms in text or graphic form. The non-invasive design allows configuration via magnetic knob or infrared setter without opening the IP68-rated housing, preserving the seal and preventing contamination. Control modes include local operation, remote switching, analog input, and fieldbus protocols. Optional explosion-proof certifications and a split-type variant for extreme conditions provide flexible, dependable automation.

How does the absolute encoder work without batteries?
We use a patented BM18 multi-turn absolute encoder that employs non-contact magnetic sensing. This technology retains valve position data across power cycles without relying on battery backup, ensuring consistent performance and reducing maintenance.
Features
Non-Invasive Setup and Diagnostics: Magnetic knob and infrared setter allow complete access to settings and alarms without breaking the enclosure seal, preserving IP68 protection.

Non-intrusive Design High-Visibility Display: The dot-matrix LCD shows torque, position, and diagnostic messages with 1% resolution, complemented by LED indicators for limit positions.
Versatile Control Modes: We equip the actuator to handle field control, remote switching, analog modulation, and fieldbus protocols (Profibus-DP, Modbus, DeviceNet, FF, Hart).
Multi-Layered Protection: Torque overload, motor overcurrent, automatic phase adjustment, phase loss, and thermal protection work together to ensure safe operation.
Patented Position Sensor: The BM18 absolute encoder provides accurate position feedback without batteries, using non-contact measurement for long-term reliability.
Adjustable Torque Limits: Users can set torque protection values via the on-screen menu, tailoring the actuator’s response to specific valve requirements.
Split Version for Harsh Conditions: The BD/BDM-C8F separates electronics from the actuator body, allowing remote mounting of the controller in high-temperature or high-vibration areas.

Split-type Actuator Control Box
Electric Multi-turn Actuator Specifications
| Parameter | Details |
|---|---|
| Power Options | Three-phase: 380Vac ±10% 50Hz±2%; Single-phase: 220Vac ±10% 50Hz±2%; other voltages and frequencies available on request |
| Torque Capacity | 50 N·m to 3,500 N·m (expandable with gearboxes up to 300,000 N·m) |
| Output Speeds | 12, 24, 36, 48, 72, 96, 144 rpm (model dependent) |
| Control Inputs | 4-20mA analog, dry contacts, DC24V/AC220V, fieldbus modules |
| Feedback Outputs | 4-20mA position, up to 4 configurable relays (bistable or monostable), alarm relay |
| Temperature Range | -30°C to +70°C (special ranges available) |
| Environmental Seal | IP68 (submersible at 2m for 48 hours) |
| Hazardous Area | Ex db IIC T4 Gb (gas) / Ex tb IIIC T130°C Db (dust) |
| Mounting | ISO 5210:2017, GB/T12222-2023, JB2920-81 flanges |
| Construction | Aluminum alloy housing with double-seal design |
Related Product
We offer the BD/BDM-C8F split-type intelligent electric actuator. It is designed for installations where the actuator body must withstand high temperatures or constant vibration. This configuration places the electronic control unit in a separate enclosure. It links to the actuator by a standard 10-meter cable. You can specify longer cables during ordering if your installation requires greater separation. The split design retains all the intelligent features of the integrated model, including the non-invasive interface, absolute encoder, and fieldbus connectivity, while allowing you to protect sensitive electronics from harsh process conditions.







