Overview
The Electro-Sensors 906 is a Hall Effect shaft speed sensor engineered for accurate, reliable speed monitoring in industrial automation and hazard detection systems. Water-resistant and built with a threaded aluminum housing, this sensor uses magnet-sensing Hall Effect technology to generate clean digital pulse signals immune to electrical noise. Supplied with a 10 ft cable, mounting bracket, and connector, the 906 is ready for immediate installation in dust, moisture, and grease-laden environments.
Key Features
- Hall Effect Technology: Magnet-sensing Hall Effect IC’s produce digital pulse signals with true zero speed operation, square-wave output, and immunity to electrical noise
- NPN Open-Collector Output: Square-wave pulse frequency output with 5-24 VDC powered operation
- Water-Resistant Design: Water resistant and suitable for industrial applications, including environments where dirt, dust, grease, or moisture are present
- Non-Contact Sensing: Recommended gap distance of 1/4 inch ±1/8 inch with gap flexibility that makes the sensor tolerant of vibration, shaft run-out, misalignment, and industrial environments
- Easy Integration: Interfaces directly with speed switches, tachometers, counters, signal conditioners, or PLCs
- Bidirectional Option: Quadrature (bidirectional) option with two sensors designed for applications requiring both speed and direction information
Technical Specifications
- Power Supply: 5–24 VDC
- Output Type: NPN open-collector square-wave pulse
- Sensor Technology: Hall Effect (magnet-sensing)
- Housing Material: Threaded aluminum body
- Cable Length: 10 ft PVC
- Mounting: Bracket assembly included
- Sensing Gap: 1/4 inch ±1/8 inch (recommended)
- Duty Cycle: 50/50 (with matched pulser disc)
- Environmental Rating: Water-resistant
- Operating Principle: Non-contact, zero-speed capable
Typical Applications
- Motor and pump speed monitoring in HVAC and process control systems
- Conveyor belt speed verification and chain drive supervision
- Hazard detection and equipment safeguarding on rotating machinery
- Overspeed and underspeed alarm triggers in industrial automation
- Machine health monitoring and predictive maintenance programs
- Tachometer and counter signal generation for data acquisition
Compatibility & Replacements
Compatible With
- Allen-Bradley PLC digital I/O modules and CompactLogix controllers
- Siemens S7-1200, S7-1500, and LOGO PLC systems
- Mitsubishi FX and iQ series PLCs
- Omron CP and CJ series controllers
- Generic speed switches, tachometers, counters, and signal conditioners
- Any control system with 5-24 VDC digital input capability
Replaces / Drop-In Replacement For
- Electro-Sensors 906 standard aluminum-body variants (all revision levels)
- Earlier 906 Hall Effect models with PVC cable
- Electro-Sensors 906 AL Body (Part No. 775-000500)
- Electro-Sensors 906 SS Body (Part No. 775-000400) — with mechanical adapter
Works With
- Electro-Sensors Model 255 Pulser Disc with evenly spaced magnets of alternating polarity
- Electro-Sensors split collar pulser wraps
- Any magnetic pulser disc or encoder with alternating magnetic poles
- Standard 24 VDC industrial control systems and DCS platforms
- SCADA and HMI systems configured for frequency or pulse counting
