The JCA-158D Hammer-Type Surface resistance tester is a highly integrated, microcomputer-displayed, portable insulating surface Resistance Tester (high-resistance meter). It is also equipped with a high-precision digital temperature and humidity sensor. The internal test voltage automatically switches between DC 10V and DC 100V. It directly displays the resistance value digitally, featuring high accuracy, fast display, good stability, and easy reading. This instrument is suitable for testing anti-static products such as anti-static shoes, anti-static plastic and rubber products, and anti-static raised floors in computer rooms, as well as measuring the insulation resistance of electronic and electrical products.

The JCA-158D Hammer-Type Surface Resistance Tester (high-resistance meter) is suitable for measuring the insulation resistance of insulating materials, electrical products, and various components. It can also measure the insulation resistance of plastic wires and cables (without shielding layers) at different temperatures, such as the working surfaces of materials, paints, packaging bags, wrist straps, common point grounding wires, footwear, packaging materials, clothing, anti-static chairs, and static-controlled areas. Its application scope includes engineering, maintenance, quality control, incoming inspection, manufacturing, and training.

Working Principle

According to Ohm's Law, the measured resistance Rx is equal to the applied voltage V divided by the current I passing through it, i.e., R = V/I. The working principle of ordinary high-resistance meters (mainly pointer-type high-resistance meters and some commonly used digital high-resistance meters) is to keep the measured voltage V fixed and obtain the resistance value by measuring the current I flowing through the sampling resistor. It can be seen from the above formula that since the current I is inversely proportional to the resistance (not directly proportional), the displayed value of the resistance is non-linear. That is, when the resistance is infinite, the current is zero, so the zero position of the meter head is marked as ∞, where the scale is very dense and the resolution is very low. The entire scale is non-linear. In addition, when measuring different resistances, the voltage V will also change slightly, so it is difficult to improve the accuracy of ordinary high-resistance meters.

For temperature and humidity measurement, an imported original digital temperature and humidity sensor is used, which directly transmits data to the microcomputer for display. This ensures high accuracy, a wide measurement range, and intuitive reading. There is no need for manual switching of the test voltage; the microcomputer automatically switches the range and test voltage according to the magnitude of the measured resistance. The instrument will not be damaged when the test terminal is short-circuited with a high voltage of 100V, ensuring safety and reliability.