Detailed introduction of QJ23 single arm bridge:

Basic structure: It mainly consists of a proportional arm, a comparison arm, a zero pointer, and a power supply. The proportional arm, also known as the multiplier disk, adopts a differential type with a total resistance of 1000 Ω; The comparative arm is composed of four sets of resistance elements, and the resistance value can be adjusted through switch combination.

Main technical parameters: The measurement range is 1 Ω to 9.999M Ω, with an accuracy of 0.2%. The current constant of the internal zeroing instrument is less than 6 × 10-5A/mm, and the damping time is less than 4s. The power supply is usually 4.5V, provided by three No. 2 dry batteries.

Working principle: Based on the Wheatstone bridge principle, the measured resistance is connected to the "RX" two terminals. The QJ23 single arm bridge selects the appropriate magnification, presses the "B" and "G" buttons, adjusts the comparison arm, and returns the zero pointer to zero. The bridge reaches balance, and the measured resistance value is equal to the multiplier multiplied by the reading on the measuring dial.

Usage: First, insert 2 1.5V No.2 dry batteries and 1 6F22 9V laminated battery into the battery box, and perform mechanical zeroing on the zero indicator. Connect the measured resistor to the "RX" terminal, estimate its resistance value, select the appropriate multiplier, press the "B" and "G" buttons, adjust the measuring dial to reset the zero pointer, and the measured resistor value can be obtained.

Attention: During measurement, the reading on the "× 1000 Ω" measuring dial should not be 0 to ensure measurement accuracy. When measuring resistors with inductance such as motors and transformers, it is necessary to press "B" first and then "G". After the measurement is completed, "G" should be placed first and then "B". The bridge can only measure passive resistance, and it is strictly prohibited to introduce mains or other power sources from the input end of the bridge.