ABB|RET521|Protection and Control Terminal
ABB RET521 Protection and Control Terminal
Description
ABB RET521 is a multifunctional protection and control terminal designed for feeder and motor applications in utility and industrial power systems.
Features
Integrated analog input processing
Configurable binary I/O modules
DSP-based protection algorithms
Front HMI with LCD and LED indicators
Dual communication interface support
mA analog input option
Technical Specifications
Current input: 1 A or 5 A; burden < 0.25 VA
Voltage input: 100–120 V; burden < 0.2 VA
Frequency range: 50/60 Hz ±2.5 Hz (standard), extended to (0.7–1.2) × fr
Auxiliary DC supply: 24–60 V or 90–250 V ±20%; power consumption < 35 W
Binary inputs: Optocoupler-isolated; voltage options 24/48/110/220 V DC
Binary outputs: Up to 24 relay contacts; making capacity 30 A (0.2 s), breaking capacity 8 A at 250 V AC
mA input module: 6 channels, 0–20 mA (4–20 mA), Rin = 194 Ω
Operating temperature: –10°C to +55°C
Immunity: IEC 60255-22 series compliant (ESD 8 kV, burst 2.5 kV, surge 1–2 kV)
Dielectric test: 2.0 kV AC, 1 min
Insulation resistance: >100 MΩ at 500 V DC
ABB|RET521|Protection and Control Terminal
ABB|RET521|Protection and Control Terminal
ABB RET521 Protection and Control Terminal
Description
ABB RET521 is a multifunctional protection and control terminal designed for feeder and motor applications in utility and industrial power systems.
Features
Integrated analog input processing
Configurable binary I/O modules
DSP-based protection algorithms
Front HMI with LCD and LED indicators
Dual communication interface support
mA analog input option
Technical Specifications
Current input: 1 A or 5 A; burden < 0.25 VA
Voltage input: 100–120 V; burden < 0.2 VA
Frequency range: 50/60 Hz ±2.5 Hz (standard), extended to (0.7–1.2) × fr
Auxiliary DC supply: 24–60 V or 90–250 V ±20%; power consumption < 35 W
Binary inputs: Optocoupler-isolated; voltage options 24/48/110/220 V DC
Binary outputs: Up to 24 relay contacts; making capacity 30 A (0.2 s), breaking capacity 8 A at 250 V AC
mA input module: 6 channels, 0–20 mA (4–20 mA), Rin = 194 Ω
Operating temperature: –10°C to +55°C
Immunity: IEC 60255-22 series compliant (ESD 8 kV, burst 2.5 kV, surge 1–2 kV)
Dielectric test: 2.0 kV AC, 1 min
Insulation resistance: >100 MΩ at 500 V DC
