How to Test the Surface Insulation Resistance of Electrical Steel Sheets

1. What is Surface Insulation Resistance of Electrical Steel?

The surface insulation resistance of electrical steel refers to the resistance performance of the insulation coating on the surface of the steel. Electrical steel is commonly used as a core component in transformers, generators, and motors. Its surface is often coated with an insulating material to prevent inter-laminar short circuits and reduce eddy current losses. The magnitude of surface insulation resistance directly affects the electromagnetic performance and thermal effects of the electrical steel, particularly in suppressing eddy currents. Higher insulation resistance can effectively reduce eddy current losses, thereby improving the efficiency of the equipment and reducing heat generation.  

2. Why Measure Surface Insulation Resistance of Electrical Steel?

The purpose of measuring the surface insulation resistance of electrical steel is to ensure its electromagnetic performance and insulation properties, to reduce eddy current losses, prevent inter-laminar short circuits, extend equipment life, and enhance efficiency. Regular measurement ensures product quality consistency and compliance with relevant international or industry standards, such as GB/T 2521 or ASTM standards. This not only improves the performance of equipment like transformers, generators, and motors, but also ensures stability and safety under various application conditions.

3. How to Measure Surface Insulation Resistance of Electrical Steel?

TS1700 is a dedicated system for measuring the insulation resistance of the coating on electrical steel sheets. It consists mainly of a testing device (10 contact points and metal rods/conductive rubber contacts, drill bits, electric cylinder, specimen tray, etc.), a control console, a system verification standard, a computer, and testing software.

The instrument supports manual turning over to measure the interlayer resistance of electrical steel. The professional testing software automates the testing process beyond parameter setting and specimen placement. It provides real-time display of voltage, current, and pressure values during the test, while also recording each set of test data for comprehensive analysis.

Software Interfaces

4. Specification of TS1700 Surface Insulation Resistance Measuring System for Electrical Steel

4.1 Specifications of Electrical Parameters

4.2 Contact Actuator

4.3 Requirements of Specimens

• Specimen Size: ( 300 mm～500 mm ) x ( 200 mm ) (lengthxwidth)

• Specimen Thickness: 0.1 mm～1.0 mm

• Other Requirements: The surface should be clean, flat, free from spots and scratches

5. Operation Video of TS1700 Surface Insulation Resistance Measuring System for Electrical Steel