The Siemens 7SJ6211-4EB20-1FC0/EE is a versatile numerical protection relay from the SIPROTEC 4 family, primarily designed for overcurrent, feeder, and motor protection in medium and high-voltage electrical networks.
Product Parameters (Datasheet)
- Model Number: 7SJ6211-4EB20-1FC0/EE
- Series: SIPROTEC 4 7SJ62
- Housing: 1/3 x 19″ (Flush mounting)
- Current Inputs: 4 (1A / 5A software-configurable)
- Voltage Inputs: 3 (For voltage-dependent protection and measurement)
- Binary Inputs: 8 (Configurable)
- Binary Outputs: 6 (4 relays + 2 high-speed/power relays)
- Auxiliary Power (Vaux): 60V / 110V / 125V DC
- Communication: RS485 (Port B) with IEC 60870-5-103 or Modbus RTU protocol
- Protection Functions: 50/51 (Overcurrent), 50N/51N (Earth fault), 46 (Negative sequence), 49 (Thermal overload), 67 (Directional), and 27/59 (Under/Overvoltage)
Country of Origin
This precision protection device is engineered and manufactured by Siemens AG in Germany, representing the global benchmark for digital substation automation.
Application Fields
The SIPROTEC 7SJ62 series is used for comprehensive protection and control in:
- Feeder Protection: Managing radial and ring networks in utility distribution.
- Motor Protection: Safeguarding large high-voltage induction motors from stalls and thermal damage.
- Busbar Protection: Acting as back-up protection for busbar zones.
- Industrial Microgrids: Providing frequency (81O/U) and voltage stability control.
- Renewable Integration: Monitoring grid-tie parameters for wind and solar substations.
Product Usage Instructions
- Mounting: Install the relay in a standard panel cutout using the included mounting brackets. Ensure the chassis is connected to a dedicated station earth.
- Current/Voltage Wiring: Connect CT and VT secondaries to the back-terminal block. Important: Never open-circuit a live CT; use shorting blocks during maintenance.
- Power-Up: Apply the correct DC auxiliary voltage. The “RUN” LED should turn green, and the LCD will initialize.
- Configuration: Use Siemens DIGSI 4 software via the front RS232 or USB port to parameterize protection curves, I/O mapping, and logic (CFC).
- Testing: Perform secondary injection tests to verify the pick-up and trip times against the programmed settings.
Product Technical Description
The 7SJ6211-4EB20-1FC0/EE is a multi-functional numerical relay that integrates protection, control, and measurement into a single unit. It features a powerful 32-bit microprocessor that performs continuous digital signal processing of analog inputs. The “CFC” (Continuous Function Chart) logic allows users to create custom automation sequences, such as interlocking or automated switching. Its modular hardware design and conformal coating options make it highly resistant to the harsh electromagnetic environments typical of high-voltage switchgear.
Q&A (Common Questions)
Q: Can this relay be used for distance protection? A: While the 7SJ62 offers directional overcurrent (67), true “Distance Protection” (21) is typically found in the SIPROTEC 7SA series. The 7SJ62 is primarily for overcurrent and motor applications.
Q: Does it support IEC 61850 communication? A: This specific model code (1FC0) typically features RS485. For IEC 61850 (Ethernet), a different communication module (Port B) would be required.
Q: How do I reset a “Trip” alarm? A: You can reset the indicators by pressing the “LED Reset” button on the front panel or via a binary input configured for remote reset.
Q: What is the purpose of the 4th current input? A: The 4th CT input is generally used for sensitive earth-fault detection (In) using a core-balance CT or a Holmgreen connection.
Similar Model Recommendations
- Siemens 7SJ622 (Increased I/O variant)
- Siemens 7SJ61 (Simplified version without voltage inputs)
- Siemens 7SJ64 (Advanced version with synchronization)
- Siemens 7UT61 (Specialized Transformer Protection)
- Siemens 7SJ82 (Next-generation SIPROTEC 5 series)
For more information on the Siemens 7SJ6211-4EB20-1FC0/EE and our full range of SIPROTEC protection relays, please contact our technical support team.
