Application and characteristics of QJ57 DC resistance bridge:

The QJ57 type is a portable precision DC double arm bridge with Kelvin circuit. Measurement range 0. There are seven measurement ranges for 01 μ Ω~1.11K Ω. Due to the presence of an internal secondary zero point gauge and the ability to accommodate a working battery, measurements can be made without any accessories other than measuring wires. Suitable for precision measurement of various low value DC resistances, such as conductivity of metal conductors, DC shunt resistance, switch contact resistance, cable resistance, as well as DC resistance of various motors and transformer windings, in laboratories and workshops of industrial and mining enterprises, scientific research units, and even field construction sites.
The main resistance components of the bridge are made of low temperature coefficient materials and undergo strict processing and manual aging; High sensitivity, low noise, and low power consumption.

Main technical indicators.

2.1 All technical indicators of QJ57 type comply with the national standard GB393083 (tributary bridge for measuring resistance), ZBY16483 。

2.3 Allowable limit of basic error:

Elim=±C%（RN/10+x）

In the formula: Elim: allowable limit of basic error, RN: reference value

C: Accuracy Level Index X: Measurement Disk Indication

2.4 Environmental conditions for use:

a: Reference value: 20 ± 0.5 ℃ Relative temperature: 40%~60%

b: Nominal value: 20 ± 5 ℃ Relative temperature: 20%~75%

Zero finger instrument

a: The internal zeroing device has mechanical and electrical zeroing devices, and its sensitivity can be adjusted.

B: The damping time shall not exceed 4 seconds.

c: Sensitivity: When the resistance value of the bridge deviates from one level value from the equilibrium point, the pointer deflection of the zero pointer should not be less than 1 grid

d: Noise: The pointer jitter should not exceed 1/3 of the grid

e: There is an external zero pointer socket inside the battery box on the back of the bridge

Power supply: The working power supply of the bridge is R40 type 1.5V dry battery connected in parallel, and the power supply of the built-in zero pointer is a 6F22 type 9V dry battery .
Dimensions: 30mm × 250mm × 160mm

2.8 Quality: Approximately 6KG