Categories: Overcurrent Coordination

ETAP Star Coordination on Focus | Detailed Example
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Device/Equipment Specifications

The specifications used in the example using the ETAP star coordination were determined by trial and error in order to obtain the fault levels indicated in figure 1. The values for the 3-phase faults were prioritized over the 1-phase faults.

Edit the device/equipment parameters according to the following specifications and leave other fields to their default values.

Power Grid

  • Rated kV: 115
  • MVAsc 3-Phase: 4340
  • X/R 3-Phase: 17
  • MVAsc 1-Phase: 4340
  • X/R 1-Phase: 17

Power Transformer 115 kV-side Fuse

  • Manufacturer: Southern States
  • Model: HPA-PM
  • Max kV: 115
  • Speed: Medium
  • Size: 125A

Power Transformer

  • Voltage Rating kV Prim.: 115
  • Voltage Rating kV Sec.: 13
  • MVA: 15
  • Class: OA/FA/FA
  • Positive %X: 8.3
  • Positive %R: 1.43
  • Positive %Z: 8.422
  • Zero %X: 8.2
  • Zero %X: 1.96
  • Zero %Z: 8.431
  • Grounding Primary: Delta
  • Grounding Secondary: Y (Solid)

Current Transformer 13 kV-side Circuit Breaker

  • Primary: 400
  • Sec.: 5

Overcurrent Relay 13 kV-side Circuit Breaker

  • Output > click ‘Add’
  • Interlock > click ‘Add’
  • OCR: ABB REF541
  • Phase Overcurrent: ☑
  • Phase Overcurrent Curve Type: IEEE – Extremely Inverse
  • Phase Overcurrent Pickup Range: 0.1 – 5 x CT Sec
  • Phase Overcurrent Pick-up: 1.8
  • Phase Overcurrent Time Dial: 1.5
  • Phase Instantaneous: ☑
  • Phase Instantaneous Pickup Range: 0.05 – 40 x CT Sec
  • Phase Instantaneous Pickup: 18.4
  • Phase Instantaneous Delay Range: 0.05 – 300
  • Phase Instantaneous Delay (Sec): 0.05
  • Neutral Overcurrent: ☑
  • Neutral Overcurrent Curve Type: IEEE – Extremely Inverse
  • Neutral Overcurrent Pickup Range: 0.1 – 5 x CT Sec
  • Neutral Overcurrent Pick-up: 0.8
  • Neutral Overcurrent Time Dial: 3.9
  • Neutral Instantaneous: ☑
  • Neutral Instantaneous Pickup Range: 0.05 – 40 x CT Sec
  • Neutral Instantaneous Pickup: 17.5
  • Neutral Instantaneous Delay Range: 0.05 – 300
  • Neutral Instantaneous Delay (Sec): 0.05

13kV Circuit Breaker

  • Cycle: 5
  • CPT: 3

Distribution Line Section 1

  • Length: 655
  • Unit: m
  • Phase Conductor: EPRI/M.LAYER Linnet
  • Ground Wire: EPRI/S.LAYER Penguin
  • Configuration Type: Vertical
  • Height: 37.5
  • Spacing AB: 2
  • Spacing BC: 2
  • Number of Ground Wires: 2
  • GG: 0.8
  • CG: -2.5
  • Number of Earth Layers: 3
  • Layer 1 p(ohms-m): 100
  • Layer 1 Depth: 30
  • Layer 2 p(ohms-m): 20
  • Layer 2 Depth: 100
  • Layer 3 p(ohms-m): 10

100T Fuse

  • Manufacturer: Chance
  • Model: Fuse Link (T)
  • Speed: Slow
  • Size: 100A

Distribution Line Section 2

  • Length: 1165
  • Unit: m
  • Phase Conductor: EPRI/M.LAYER Linnet
  • Ground Wire: EPRI/S.LAYER Penguin
  • Configuration Type: Vertical
  • Height: 37.5
  • Spacing AB: 2
  • Spacing BC: 2
  • Number of Ground Wires: 2
  • GG: 0.8
  • CG: -2.78
  • Number of Earth Layers: 3
  • Layer 1 p(ohms-m): 100
  • Layer 1 Depth: 30
  • Layer 2 p(ohms-m): 20
  • Layer 2 Depth: 100
  • Layer 3 p(ohms-m): 10

Automatic Recloser

  • Manufacturer: Cooper
  • Model: Nova 15
  • Controller Model: Form 6
  • Sequence Operation 1st TCC: Phase – 1, Ground – 1
  • Sequence Operation to Lockout: Phase – 2, Ground – 2
  • Sequence Reclose Duration (Sec): 1
  • Operation Level: TCC1 ☑
  • TCC1 Phase Overcurrent: ☐
  • TCC1 Phase High Current: ☑
  • TCC1 Phase High Current Trip Range: 1 – 32 x TOC Pickup
  • TCC1 Phase High CurrentTrip: 1
  • TCC1 Phase High CurrentDelay Range: 0.01 – 0.15
  • TCC1 Phase High CurrentDelay (Sec): 0.01
  • TCC1 Ground Overcurrent: ☐
  • TCC1 Ground High Current: ☑
  • TCC1 Ground High CurrentTrip Range: 1 – 32 x TOC Pickup
  • TCC1 Ground High CurrentTrip: 1
  • TCC1 Ground High CurrentDelay Range: 0.01 – 0.15
  • TCC1 Ground High CurrentDelay (Sec): 0.01
  • Operation Level: TCC2 ☑
  • TCC2 Phase Overcurrent: ☑
  • TCC2 Phase Overcurrent Curve Type: ANSI – Extremely Inverse
  • TCC2 Phase Overcurrent Trip Range: 5 – 800 Primary
  • TCC2 Phase Overcurrent Trip: 560
  • TCC2 Phase Overcurrent Modifier Time Multiplier: 0.15
  • TCC2 Phase High Current: ☑
  • TCC2 Phase High Current Trip Range: 1 – 32 x TOC Pickup
  • TCC2 Phase High Current Trip: 4.75
  • TCC2 Phase High Current Delay Range: 0.01 – 0.15
  • TCC2 Phase High Current Delay (Sec): 0.01
  • TCC2 Ground Overcurrent: ☑
  • TCC2 Ground Overcurrent Curve Type: ANSI – Extremely Inverse
  • TCC2 Ground Overcurrent Trip Range: 2 – 400 Primary
  • TCC2 Ground Overcurrent Trip: 280
  • TCC2 Ground Overcurrent Modifier Time Multiplier: 0.7
  • TCC2 Ground High Current: ☑
  • TCC2 Ground High Current Trip Range: 1 – 32 x TOC Pickup
  • TCC2 Ground High Current Trip: 5.77
  • TCC2 Ground High Current Delay Range: 0.01 – 0.15
  • TCC2 Ground High Current Delay (Sec): 0.01

Distribution Line Section 3

  • Length: 3550
  • Unit: m
  • Phase Conductor: EPRI/M.LAYER Penguin
  • Ground Wire: EPRI 3 No. 10
  • Configuration Type: Horizontal
  • Height: 37.5
  • Spacing AB: 2.92
  • Spacing BC: 3.36
  • Number of Ground Wires: 1
  • CG: -4.75
  • Number of Earth Layers: 1
  • Layer 1 p(ohms-m): 1000

Distribution Line Section 4

  • Length: 3835
  • Unit: m
  • Phase Conductor: EPRI/M.LAYER Penguin
  • Ground Wire: EPRI 3 No. 10
  • Configuration Type: Horizontal
  • Height: 37.5
  • Spacing AB: 2.92
  • Spacing BC: 3.36
  • Number of Ground Wires: 1
  • CG: -4.75
  • Number of Earth Layers: 1
  • Layer 1 p(ohms-m): 1000

65T Fuse

  • Manufacturer: Chance
  • Model: Fuse Link (T)
  • Speed: Slow
  • Size: 65A

Distribution Line Section 5

  • Length: 3465
  • Unit: m
  • Phase Conductor: EPRI/M.LAYER Penguin
  • Ground Wire: EPRI 3 No. 10
  • Configuration Type: Horizontal
  • Height: 37.5
  • Spacing AB: 2.92
  • Spacing BC: 3.36
  • Number of Ground Wires: 1
  • CG: -4.75
  • Number of Earth Layers: 1
  • Layer 1 p(ohms-m): 1000

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Tags: etap relay coordination tutorialetap star coordinationHow-Toprotection coordination study
6 years ago

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