Stucke Elektronik SYMAP®M motor protection
SYMAP® M (Motor Protection) is a dedicated digital protection relay from Stucke Elektronik designed specifically for the protection, control, and monitoring of high-stakes electric motors.
1 It is widely used for large asynchronous (induction) and synchronous motors in industrial and marine environments.
1. Product Description
SYMAP® M is a multifunctional, microprocessor-based relay that provides comprehensive protection against mechanical and electrical stress.
2 Unlike standard motor starters, SYMAP® M monitors complex thermal images of the motor, protects against stalled rotors, and manages frequent starting cycles.
It integrates protection, measurement, and control (including star-delta or autotransformer starting logic) into a single, rugged unit.3
2. Technical Parameter Table
| Category | Specification |
| Power Supply | 24V DC (Standard range 18V – 36V) |
| Current Inputs | 3-phase ($I_1, I_2, I_3$) + 1 Ground ($I_o$) / 1A or 5A rated |
| Voltage Inputs | 3-phase ($U_1, U_2, U_3$) for power and phase monitoring |
| Motor Specific Protection | Thermal Overload (49), Stalled Rotor (50S), Start Intensity Monitoring, Phase Reversal (46) |
| Analog Inputs | RTD/PT100 inputs for bearing and winding temperature monitoring |
| Control Logic | Built-in PLC for motor start/stop sequences and interlocks |
| Communication | Modbus RTU, Profibus DP, CANbus, or IEC 61850 |
| Protection Speed | Processing cycle < 20ms |
| Enclosure | IP54 front panel protection; Metal housing for EMC shielding |
3. Related Models
The SYMAP® M series includes variants based on motor size and voltage:
SYMAP® M (Standard): Focused on current-based protection for LV/MV motors.
SYMAP® M-V: Adds voltage and frequency monitoring for sensitive motor applications.
SYMAP® M-Diff: Includes Motor Differential Protection (87M) for high-voltage motors to detect internal phase-to-phase faults.
SYMAP® M-Compact: A space-saving version for integration into smaller Motor Control Centers (MCC).
4. Application Cases
Marine Propulsion & Thrusters: Protecting the massive electric motors used for ship maneuvering and main propulsion.
Heavy Industry Pumps & Fans: Used in water treatment plants, cooling towers, and mine ventilation systems.
Compressors: Protection for large-scale industrial air or gas compressors in the Oil & Gas sector.
Conveyor Systems: Managing the high-torque start-up phase and overload protection for mining conveyors.
SYMAP®M
5. Product Advantages and Features
Advanced Thermal Modeling: Calculates the motor’s “Thermal Image” in real-time to prevent overheating while allowing maximum operational flexibility.
Comprehensive Start-up Monitoring: Specifically monitors the number of starts and the time between starts to prevent insulation degradation.
Integrated Control: Can replace external timing relays and small PLCs by managing the entire starting sequence (e.g., controlling the main, star, and delta contactors).
Fault Diagnostics: Records the “Trip Profile,” allowing technicians to see exactly what the current and voltage were at the millisecond of the fault.
Safety & Redundancy: Built with the Stucke 3-CPU architecture for fail-safe operation in critical environments.4
6. Other Models in the Same Series
SYMAP® is a modular platform covering the entire power distribution board:5
SYMAP® G: Generator Protection.
SYMAP® EC / ECG: Engine Control and integrated Generator Protection.
SYMAP® F: Feeder Protection for distribution lines.
SYMAP® BC: Bus-tie Control for managing busbar segments.
SYMAP® T: Transformer Protection.