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HT & LT Breaker Testing & Commissioning
Precision for Safety & Reliability

Circuit breakers are the first line of defense in any electrical network, designed to detect and isolate faults instantly, preventing equipment damage, fire hazards, and power outages. Our comprehensive testing ensures fault-free operation from day one.

Our Testing Process Get Quote

Types of Breakers We Test & Commission

SF₆, Vacuum (VCB), and Air (ACB) types across voltage ranges from 415 V to 400 kV

SF₆ Circuit Breakers

Application: 66 kV to 400 kV transmission and substation networks

Advantages:
  • Compact design
  • High interrupting capacity
  • Arc quenching efficiency
Testing Focus:
  • Gas pressure checks
  • Leak detection
  • Contact resistance
  • Timing analysis

Vacuum Circuit Breakers

Application: 11 kV to 33 kV distribution networks

Advantages:
  • Minimal maintenance
  • No gas refilling
  • Long service life
Testing Focus:
  • Vacuum integrity
  • Mechanical operations
  • Contact erosion

Air Circuit Breakers

Application: 415 V to 1 kV industrial panels

Advantages:
  • Cost-effective
  • Easy maintenance
  • Reliable in LV applications
Testing Focus:
  • Trip unit calibration
  • Contact resistance
  • Closing/tripping speed

Why Breaker Testing Before Commissioning is Critical

Safety

Prevents malfunction that could lead to catastrophic faults

Accuracy

Ensures correct tripping at set current/voltage thresholds

Reliability

Verifies breaker will operate even after long idle periods

Compliance

Meets IS 13118, IS 13947, IEC 62271 standards

Longevity

Prevents early wear and reduces maintenance costs

Cost Effective

Early detection prevents expensive failures and downtime

Our HT & LT Breaker Testing & Commissioning Process

Comprehensive testing following IS 13118, IS 13947, IEC 62271, IEEE C37 standards

1. Pre-Installation & Visual Inspection

  • Check for shipping damage, corrosion, loose parts
  • Verify nameplate details—rated voltage, current, short-circuit capacity
  • Confirm mechanical parts operate smoothly
  • Inspect contacts for wear or damage
  • Verify auxiliary systems and connections
  • Check operating mechanism alignment

2. Electrical & Mechanical Testing

Insulation Resistance (IR) Test
Measures insulation between phases and to earth
Contact Resistance Test (CRM)
Detects worn contacts or loose connections
Timing Test
Measures opening/closing time, pole synchronism
Vacuum Integrity Test (VCB)
High voltage test across open contacts
SF₆ Gas Quality Test
Checks moisture, purity, and decomposition products
Primary Injection Test
Verifies breaker trips at set current threshold

3. Protection Relay Coordination & Integration

  • Ensure breaker trip curves match system protection design
  • Calibrate relay settings for overload, short-circuit, and earth fault protection
  • Test breaker interlocks and synchronism check relays

4. Commissioning Procedure

  • Energize breaker under controlled conditions
  • Record operational parameters under no-load and load conditions
  • Perform final tripping tests under simulated fault
  • Submit detailed commissioning report and compliance certificate

Real-World Example

SF₆ Breaker Commissioning at 220 kV Substation

8 SF₆ Breakers

220 kV Substation, Madhya Pradesh - 2023

Project Highlights

Tests Performed: Gas quality analysis, timing test, CRM, primary injection

Challenge: Breakers stored for over a year before installation

Solution: Pre-commissioning overhaul and lubrication before testing

100%

Compliance test pass rate

Zero Faults

Energization without incidents

Safety & Quality Standards We Follow

IS Standards

IS 13118 (HV Breakers), IS 13947 (LV Breakers)

International Standards

IEC 62271 (HV), IEC 60947 (LV), IEEE C37

Safety Practices

Lockout/tagout, PPE compliance, safe discharge protocols