P3U20 UNIVERSAL PROTECTION RELAY

P3U20 Universal Protection Relay Technical Specifications

General Information

• Type: Multifunction universal protection relay
• Application:
• Feeder protection
• Motor protection
• Product series: PowerLogic / Easergy P3
• Mounting: Flush / Rack, disconnectable

Power Supply

• Auxiliary supply:
• 48230 V AC/DC OR
• 110230 V AC/DC (model dependent)
• Frequency: 50/60 Hz
• Power consumption:
• Typical: ~15 W
• Max: ~25 W

Measuring Inputs

• Current inputs (CT):
• 1 A / 5 A (phase currents)
• Residual current input available
• Voltage inputs (VT):
• 100 V / 110 V

I/O Configuration

• Digital Inputs (DI): ~10
• Digital Outputs (DO):
• Typically 5 + watchdog or up to 10 (variant-based)
• Analog Inputs/Outputs: Not provided (in standard versions)

Protection Functions

Includes a wide range of ANSI protections:

Current & Fault Protection

• Phase overcurrent (50/51)
• Earth fault (50N/51N, 51G)
• Directional earth fault (67N)
• Negative sequence (46)
• Undercurrent (37)

Motor & Thermal Protection

• Thermal overload (49)
• Locked rotor / starting time (48/51LR)
• Motor restart inhibit (66)

System Protection

• Over/under frequency (81O / 81U)
• ROCOF (81R)
• Capacitor protection (51C, 59C)

Additional Features

• Breaker failure (50BF)
• Recloser (79)
• Fault locator
• Switch-on-to-fault (SOTF)
• CT/VT supervision

Communication & Protocols

• Protocols supported:
• IEC 61850
• Modbus (RTU & TCP)
• DNP3
• IEC 60870-5-101 / 103
• Ports:
• Ethernet (RJ45 / fiber optional)
• RS-485
• USB (front)
• Redundancy: PRP / RSTP
• Time sync: SNTP / IRIG-B

Cybersecurity Features

• Password protection
• Role-based access control
• Firmware authentication
• Port hardening

Monitoring & Control

• Circuit breaker monitoring
• Trip circuit supervision
• Event & fault recording
• Self-diagnostics

Environmental & Physical

• Operating temperature: approx. -40C to +60C
• Protection class: IP54
• Dimensions:
• 176 171 226 mm
• Weight: ~2.5 kg

Additional Features

• LED indications (status & alarms)
• Programmable logic & setting groups
• Harmonic measurement & THD calculation