VCB Testing – Tung Hoa

Project Introduction

The project focused on safety verification and technical testing for VCB systems before operation. This is a mandatory step to ensure the medium-voltage system of the Tung Hoa factory complies with strict utility regulations.

System Role and Function

The VCB is the most important protection device in medium-voltage panels:

• Performing 22KV switching under load or during faults.
• Protecting transformers and underground cables from large short-circuit currents.
• Ensuring operator safety thanks to the vacuum arc extinguishing chamber.

Detailed Construction Items

Specialized testing items:

• High-voltage AC testing (AC Hi-pot) for VCB insulation.
• Protecting transformers and underground cables from large short-circuit currents.
• Checking opening/closing times and pole simultaneity.
• Testing trip/close coils and interlocking control circuits.

Advanced Technical Solutions

We used modern digital timing sets to ensure the time discrepancy between phases is minimal (less than 2ms), effectively suppressing arcs and protecting equipment longevity.

Standardized Execution Process

VCB testing steps:

• Step 1: Visual inspection and cleaning of insulation poles.
• Step 2: Performing static measurements (Insulation resistance, contact resistance).
• Step 3: Performing dynamic measurements (Opening/closing times).
• Step 4: High-voltage testing to determine vacuum chamber integrity.
• Step 5: Generating test reports and applying certification labels.

Project Highlights

Project results:

• 100% of equipment met energizing standards, with no incidents during actual operation.
• Test reports quickly approved by utility authorities.
• Provided additional advice on effective preventive maintenance solutions.
• Executed swiftly, meeting the client's site handover schedule.