Precision Resistance Box 0-9999/0-9999.9 Adjustable Decade Resistor Teaching Instrument for Physical Teaching Experiment Tools Features: 1.100% new and high-quality products. 2.It can verify the partial Ohm's law of the circuit. 3.Used as an additional resistor to expand the voltage range. 4.Used to measure unknown resistance. 5.Used as electromotive force and internal resistance to measure power supply. 6.Used as a known resistor in a circuit to regulate the required current. Description: The 23022 teaching resistance box is designed for students in ordinary high schools, technical secondary schools, and universities to conduct the following electrical experiments: verifying the Ohm's law of some circuits; using it as an additional resistor to expand the range of a voltmeter; Used to measure unknown resistance: Used to connect known resistance into a circuit to adjust the required current; Used for measuring electromotive force and internal resistance of power sources. It is an essential instrument in electrical experiments. Structure and usage method The 23022 teaching resistor box adopts a rubber sealed structure. The resistance value transformation method is in the form of a knob switch, which relies on the electric brush rotating to different positions to achieve the purpose of resistance value transformation. Panel layout, wiring principle. The resistance components of this instrument are made of highly stable precision alloy manganese copper wire wound non-inductively on the porcelain skeleton. After strict screening, testing, aging, and impregnation treatment, the resistance value is stable and correct. When in use, connect the circuit through two terminals on the panel and adjust the five knobs to get a resistance value of 0 999.92. The resistance reading is obtained by multiplying the readings of the indicated points on each knob by the multiples above and adding them together. Generally, the values of the indicated points on each knob are sequentially read from high multiples to low multiples, and this value is the resistance reading. The resistance is 5083.2 Specifications: 1.Accuracy level: Level 1. 2.Adjustable range of resistance value: 0~9999.9/0~9999, with a minimum step value of 0.10/1. 3.Operating temperature: 0-40C. 4.Relative temperature: 25%