Introduction
Laxven’s Rotational Speed Sensors are designed for traction motor speed sensing in three-phase locomotives. These active sensors offer 100% compatibility with existing passive Weigand sensors and are more reliable. The sensors provide redundant outputs to represent direction and speed and are crucial for accurate speed control, adhesion control, and slip control during starting and braking operations.
Laxven also offers a model for IGBT-based locomotives, with two independent channels for speed output and a power supply ranging from 8V to 36V. These sensors are robust, durable, and designed to withstand the harsh conditions of locomotives.
System Overview
- The Rotational Speed Sensor is used in three-phase locomotives to calculate the locomotive speed and manage various functions like speed limits, constant speed control, and adhesion control during starting and braking.
- The system works effectively even at crawling speeds, where sensor accuracy is critical for slip control.
- The sensor outputs provide information about the direction and speed of the locomotive, ensuring seamless operation in various conditions
Salient Features
| Feature | Description |
| Sensor Type | Hall effect-based speed sensor |
| Redundancy | Dual-channel redundant system for reliability |
| Direction & Speed | Speed and direction can be detected with just one output |
| Signal Conditioning | In-built signal conditioning and filtering |
| Air Gap Tolerance | Works even with an air gap of 3mm |
| Durability | Withstands shocks, vibrations, and extreme temperatures encountered in locomotives |
| Environmental Immunity | Immune to dust and grease |
| Railway Compliance | Complies with IEC 60571 and IEC 61373 standards |
| Low Maintenance | Requires less maintenance with long-term reliability |
| Power Supply Range | Works from 50V to 140V DC, suitable for Indian Railway locomotives |
| Built-in Protections | Reverse Polarity, Over Voltage, Over Current, and Short Circuit protection |
| Surge and EMI Protection | High-capacity filters for Surge/Transient suppression and EMI/EMC suppression |
| Enclosure Material | Made of high-grade Stainless Steel (SS-304) |
| Signal Noise Protection | Shielded cables eliminate noise in the system |
| High Reliability Connectors | Uses circular connectors for enhanced reliability |
Technical specification
| Parameter | Details |
|---|---|
| Power Supply Voltage | 77V DC to 137.5V DC from locomotive Battery (Nominal: 110V DC) |
| Power Consumption | < 3 Watts |
| Sensor Wheel | 120 pulses per revolution (can be customized as per requirement) |
| Air Gap | 3mm |
| Railway Compliance | IEC 60571, IEC 61373 |
| EMI/EMC Compliance | IEC 61000 |
| Temperature Range | -10°C to +85°C |
