VTRI-318S Transformer Turns Ratio Tester – 3 Phase Vector Group Testing

VTRI-318S Transformer Turns Ratio Tester is an advanced automatic 3 phase transformer turns ratio tester designed for accurate measurement of transformer turns ratio, vector group, polarity, phase angle and excitation current. It is ideal for transformer manufacturers, repair workshops, utilities, and EPC contractors.

Why Use a Transformer Turns Ratio Tester?

Transformer Turns Ratio (TTR) testing is a mandatory diagnostic test to verify winding integrity, detect shorted turns, identify incorrect tap connections, and ensure compliance with IEC & IS standards. The VTRI-318S simplifies this process using one-time 3-phase connection.

Key Features of VTRI-318S Turns Ratio Tester

• Measures Turns Ratio, HT & LT Voltages, Excitation Current
• Vector Group Detection (Y-y, Y-d, D-y, D-d)
• Polarity, Phase Angle & Percentage Deviation Measurement
• Large 7” TFT Touch Display for easy operation
• Single-connection 3-Phase Testing (No Re-connection Required)
• Manual & Automatic Test Modes
• Ideal for Transformers up to 10 MVA
• Internal Memory for up to 25 Test Results
• PC Connectivity via RS-232
• MIL-grade HT & LT Terminals for reliable field use

Technical Highlights

• HT Excitation Voltage: 55V AC
• Auxiliary Supply: 230V AC
• 3-Phase Ratio Measurement in One Test

Applications

• Power & Distribution Transformer Testing
• Transformer Manufacturing Plants
• Transformer Repair & Rewinding Workshops
• Electrical Utilities & Substations
• Commissioning & Preventive Maintenance

VTRI-318S vs Conventional Turns Ratio Testers

Frequently Asked Questions – Transformer Turns Ratio Tester

What is a transformer turns ratio tester?

A transformer turns ratio tester measures the ratio between high voltage and low voltage windings to ensure correct transformer operation and detect winding faults.

Is turns ratio testing mandatory?

Yes, TTR testing is mandatory during transformer manufacturing, installation, repair, and preventive maintenance.

Can VTRI-318S test 3-phase transformers?

Yes, VTRI-318S is a true 3-phase transformer turns ratio tester with single-connection testing.

What vector groups are supported?

The instrument supports Y-y, Y-d, D-y, and D-d vector group testing automatically.

What is the maximum transformer capacity supported?

VTRI-318S is suitable for transformer testing up to 10 MVA.