GE Multilin | 745-W2-WP5-G5-HI | Transformer Management Relay

The 745 Transformer Protection System is a high speed, multi-processor based, threephase, two or three winding, transformer management relay intended for the primary protection and management of small, medium and large power transformers. 

Technical specifications:

• Transformers: Two-winding or three-winding
• Frequency: 50 or 60 Hz nominal
• Frequency Tracking:
  • 40 to 65 Hz for 0.05 × CT < current ≤ 1 × CT
  • 5 to 65 Hz for current > 1 × CT
  • 2 to 65 Hz for voltage > 50% of VT (only if voltage sensing is enabled)

CONTROL POWER

• Options: LO/HI (specified when ordering)
• LO Range: 20 to 60 V DC; 20 to 48 V AC at 48 to 62 Hz
• HI Range: 90 to 300 V DC; 70 to 265 V AC at 48 to 62 Hz
• Power: 30 VA nominal, 40 VA maximum
• Total loss of voltage ride-through time (0% control power): 16.7 ms
• Fuse Current Rating: 3.15A (fuse not accessible)
• Fuse Type: 5 × 20 mm slow-blow Littelfuse, high breaking capacity; model 2153.15

PHASE CURRENT INPUT

• Source CT: 1 to 50000 A primary; 1 or 5 A secondary
• Relay Input: 1 A or 5 A (specified at order)
• Burden: Less than 0.2 VA at rated load per phase
• Conversion Range: 0.02 to 46 × CT at 50/60 Hz nominal frequency
• Accuracy:
  • At < 4 × CT: ±0.25% of 4 × CT (±0.01 × CT) at 50/60 Hz nominal frequency
  • At ≥ 4 × CT: ±0.5% of 46 × CT (±0.2 × CT) at 50/60 Hz nominal frequency
• Overload Withstand: 1 second at 80 times rated current; 2 seconds at 40 times rated current; continuous at 3 times rated current

GROUND CURRENT INPUT

• Source CT: 1 to 50000 A primary, 1 or 5 A secondary
• Relay Input: 1 A or 5 A (specified at order)
• Burden: Less than 0.2 VA at rated load
• Conversion Range: 0.02 to 46 × CT
• Accuracy:
  • At < 4 × CT: ±0.25% of 4 × CT (±0.01 × CT)
  • At ≥ 4 × CT: ±0.5% of 46 × CT (±0.2 × CT)
• Overload Withstand: 1 second at 80 times rated current; 2 seconds at 40 times rated current; continuous at 3 times rated current

VOLTAGE INPUTS

• Source VT: 2 to 600 kV / 60 to 120 V
• Source VT Ratio: 1 to 5000 in steps of 1
• Relay Input: 60 to 120 V phase-neutral
• Burden: Less than 0.025 VA at 120 V
• Maximum Continuous Input: 273 V
• Maximum Accuracy Input: 260 V (full-scale)