Description

The ABB DSSR122 48990001-NK is a microprocessor-based digital static overload relay designed for comprehensive motor protection in industrial automation systems. As part of ABB’s renowned DSSR series, this 48990001-NK variant delivers advanced thermal modeling and electrical fault detection for motors up to 25A. The relay continuously monitors current, voltage imbalance, and phase loss using True RMS measurement, providing Class 20 trip curves compliant with IEC/EN 60947-4-1 standards. Its modular design integrates seamlessly with ABB contactors like the A-series, while the DSSR122 48990001-NK‘s configurable trip thresholds and restart inhibit timers prevent motor damage during frequent start-stop cycles. Featuring a backlit LCD display for real-time current readout and fault diagnostics, this unit supports Modbus RTU communication via optional module for integration into building management systems. The ABB DSSR122 48990001-NK is engineered for harsh environments with an operational range of -25°C to +60°C and immunity to vibration (5g @ 10-150Hz), making it ideal for HVAC, pump control, and material handling applications where motor reliability is critical.

ABB DSSR122 48990001-NK

Technical Specifications

Main Features and Advantages

Precision Thermal Modeling: The DSSR122 48990001-NK emulates motor heating characteristics using real-time I²t algorithms, accounting for cooling times during stops to prevent nuisance tripping.

Multi-Layer Diagnostics: Continuously tracks six fault types with timestamped event logging (last 10 trips). Phase imbalance detection as low as 5% prevents single-phasing damage.

Versatile Integration: Plug-in CM-ARD communication module enables Modbus parameter adjustment and remote monitoring without opening control cabinets. The relay’s memory retains settings during power loss.

User-Adaptive Configuration: Rotary switches and pushbuttons allow programming without external tools. The LCD displays real-time current (phase-by-phase) and predictive thermal capacity percentage.

Robust Construction: 6kV surge immunity (IEC 61000-4-5) and 50g shock resistance ensure reliability in vibrating environments like crusher plants.

Application Field

The ABB DSSR122 48990001-NK safeguards motors across critical infrastructure. In water treatment facilities, it protects pump motors against dry-running via undercurrent detection. Manufacturing plants utilize its ground fault protection (5–30% adjustable) for conveyor motors in explosive dust environments. HVAC systems leverage the relay’s automatic restart lockout after overload to prevent compressor damage.

For material handling, the DSSR122 48990001-NK‘s vibration-resistant design ensures stable operation in crane trolley drives. In food processing, its NEMA 12-rated enclosure (with optional kit) withstands washdown chemicals. Mining operations depend on its phase loss protection during voltage sags. The Modbus capability enables centralized monitoring of motor health in distributed systems like airport baggage handling.

Related Products

ABB CM-ARD: Modbus RTU communication module for DSSR122

ABB A30-30-10: 25A contactor for direct relay mounting

DSSR120: Lower-current variant (0.1–12A)

DSRD-22: Diagnostic display module for remote status

ABB 1SVR730850R0100: Auxiliary contact block

ABB CP-S-24DC: 24V DC power supply for control circuits

TA25DU: Thermal overload relay alternative

ABB DSSR122 48990001-NK

Installation and Maintenance

Pre-installation preparation: Verify motor FLA (Full Load Amperes) and set current dial accordingly. Ensure CT leads are routed away from power cables (>100mm separation). Configure trip class via rotary switch before energizing.

Maintenance recommendations: Perform annual calibration check using reference current source. Clean airflow vents with dry compressed air quarterly. After fault trips, use the DSSR122 48990001-NK‘s event log to identify root cause before resetting. Replace unit if LCD shows persistent segment failure.