The ETCR EM3900 lightning protection standard resistor consists of nine 1/2W high-precision wirewound resistors. Calibration allows for direct switching and testing without changing test leads. Its stable performance and robust construction make calibration and 

testing particularly convenient. The high-precision wirewound resistors feature a maximum accuracy of 0.05%. Available resistance values include 1mΩ, 10mΩ, 100mΩ, 1Ω, 10Ω, 100Ω, 1kΩ, and 100kΩ, fully meeting the 10⁻³ to 10⁵Ω range specified in 

National Meteorological Administration Order No. 38, "Administrative Measures for the Qualification and Inspection of Lightning Protection Devices." This standard resistor is primarily used for calibrating instruments such as ground resistance testers and equipotential testers. 

It is widely used in building quality inspection stations, supervision companies, construction companies, lightning protection companies, and power companies.

Product Features

1. Made of high-precision wirewound resistors, it offers stable performance and robust construction, making calibration and testing particularly convenient.

2. It fully meets the 10⁻³ to 10⁵Ω range specified in National Meteorological Administration Order No. 38, "Administrative Measures for the Qualification and Inspection of Lightning Protection Devices."

3. 8 output levels: 1mΩ, 10mΩ, 100mΩ, 1Ω, 10Ω, 100Ω, 1kΩ, 100kΩ.

Commonly Used Test Instruments in the Lightning Protection Industry