Overview
Explosion-proof RS485 / Modbus-RTU absolute encoders (SAS-M78) are designed for hazardous industrial environments where flammable gases, vapors, or combustible dust may exist. These encoders provide deterministic absolute position feedback via the RS485 interface with Modbus-RTU protocol while complying with certified explosion-protection standards.
The 78mm reinforced housing ensures safe installation in petrochemical, chemical, and mining applications, supporting motion control and safety-critical systems.
Key Functional Features
- RS485 Interface with Modbus-RTU protocol for deterministic position communication
- Single-turn resolution: up to 21 bits
- Multi-turn resolution: up to 14 bits
- Optional incremental output for dual-feedback applications
- Stable operation under vibration, shock, and industrial electrical noise
- Explosion-proof housing certified for hazardous areas
- Environmental protection: IP65 / IP67
These features provide reliable absolute position feedback in safety-critical, hazardous industrial applications.
Mechanical Protection and Mounting
The SAS-M78 series features robust mechanical design for explosion-proof compliance:
- Clamp flange – ensures secure and repeatable installation
- Blind hollow shaft flange – facilitates integration onto existing shafts without compromising housing integrity
Reinforced metal housing and sealed cable entries prevent ignition of surrounding flammable atmospheres, ensuring long-term safety and performance.
Shaft Interface Options
- Solid Shaft – suitable when shaft alignment can be controlled, offering a stable mechanical reference
- Blind Hollow Shaft – ideal for retrofit or space-constrained layouts, reducing mechanical components while maintaining explosion-proof compliance
Proper selection and careful alignment are critical to maintain both encoder performance and hazardous-area certification.
Environmental Suitability
- Designed for indoor and outdoor hazardous environments
- Resistant to continuous vibration and mechanical stress
- Rated for typical industrial temperature ranges
- Protected against dust, moisture, and contaminants
Correct grounding, cabling, and adherence to hazardous-area installation standards are essential for safe and reliable operation.
Typical Applications
- Petrochemical and chemical process machinery
- Mining equipment in combustible dust zones
- Oil and gas production systems
- Offshore platforms and hazardous energy facilities
Explosion-proof RS485 / Modbus-RTU encoders provide both precise motion control feedback and compliance with safety-critical requirements.
Engineering Selection Summary
The SAS-M78 explosion-proof RS485 / Modbus-RTU absolute encoder series combines reinforced housing, deterministic Modbus-RTU feedback, and robust mechanical design. Engineers must consider environmental classification, shaft interface, and proper installation to ensure safety, performance, and long-term reliability in hazardous industrial environments.
Technical Reference
For detailed specifications and mechanical drawings, refer to the corresponding product documentation during final selection.
Reference：Explosion-Proof RS485 / Modbus-RTU Absolute Encoder SAS-M78
