Measuring the total current which flows along the insulation coating of the sample when pressure is applied via several contacts. Conversion of the measured value to an equivalent surface resistance. Suitable especially for quality control of insulation coating.
Constructed from 2 main components:
Voltage supply unit
Testing device with hydraulic pump
The test head consists of two longitudinal rows of five vertically mounted steel rods which are free to move axially against the surrounding spiral springs. A stainless steel measuring contact is positioned at each end of each rod. It is possible to move the test head hydraulically perpendicular to a surface.
The testing contacts are pressed onto the insulation coating with a pressure of 129N per electrode. An electrical contact to the steel sheet is created with a spiral drill. If the resistance is finite a current proportional to the resistance flows through the insulation coating.
Surface resistance
Resistance distribution
Coating thickness (optional)
Determination of surface resistance of individual samples of electrical steel and punched parts
Quality control of insulation coating
Manually operated or fully automatic version
Preparation and execution of the measuring process according to ASTM-standard A 717-81