1、 Product Introduction
The XWBJ and XQBJ series large circular graph transistor automatic balance recording and regulating instruments (hereinafter referred to as instruments) are widely used in metallurgical, chemical, petroleum, light industry, textile, power plant and other industrial and mining enterprises as well as various scientific research units for automatic measurement, indication and recording of the measured object after being matched with certain transmitters.
The XWBJ series instruments are potentiometers that can be used in conjunction with various standard calibrated thermocouples and radiation temperature sensors to measure temperature, or with corresponding transmitters that generate DC potential or current to measure pressure, measure or perform component analysis. The XQBJ series instruments are balanced bridge (DC) and can be used in conjunction with various standard graduated resistance thermometers to measure temperature.
If the instrument is equipped with various types of additional devices, it can also achieve automatic control and adjustment of the measured object, such as surface or internal electrical contact devices, cam or program control devices, time proportion adjustment devices, weighing and accumulating devices, etc.

2、 Working principle
The XWBJ series potentiometer uses voltage compensation method to measure the measured parameters. When the measured DC potential is added to the measurement bridge circuit through a filtering unit, the unbalanced voltage generated by the unequal size of the measured potential and bridge circuit due to their reverse direction series connection is amplified by a transistor and drives the reversible motor. On the one hand, the reversible motor drives the sliding resistance contacts of the measuring bridge circuit to generate compensation potential and balance the measured signal in the bridge circuit; On the other hand, it drives the pointer to indicate the corresponding measured parameter, and the recording pen draws the value of the measured object on the recording paper. The bridge resistance RW (instead of R2) of the instrument for measuring temperature with a thermocouple compensates for the change in electromotive force caused by the temperature change at the cold end of the thermocouple with copper, ensuring the accuracy of the instrument within the range of 00-500C.
The XQBJ series balanced bridge and resistance thermometer Rr are sensitive components for temperature measurement, which are connected to one arm of a balanced bridge circuit. When the change in the measured object causes a change in the resistance value of the resistance thermometer, the balance of the bridge circuit is disrupted, resulting in an unbalanced signal that is amplified by a transistor amplifier and drives a reversible motor. On the one hand, the reversible motor drives the sliding resistor contacts to move, rebalancing the bridge circuit, and on the other hand, it drives the pointer and recording pen to indicate and record the corresponding measured parameter values.

3、 Characteristics
The effective curvature of the ruler is 742mm in total, equipped with visible pointers for clear and convenient reading;
Keeping the paper running at a constant speed and replacing it once a day is beneficial for clarifying the responsibilities of shift handover in daily production;
Simple structure, stable and reliable performance, easy to maintain.

4、 Technical parameters:
Working climate conditions:
Environmental temperature: 0~500C
Relative temperature: 30%~85%
Working power supply: AC220V50Hz
Basic indication error: ± 0.5%
Record basic error: ± 1%
Indicating insensitive area: 0.25%
Scale scale total length: 742mm
Effective length of the center on the recording paper: 110mm
Full travel time: ≤ 5s
Rated external resistance on input side:
Potentiometer ≤ 1K Ω
Balanced bridge ≤ 1.5K Ω
Record paper feed speed: 24 hours/week
Power consumption: approximately 40W
Weight:<23kg
Given error: ± 1%
Dimensions: 420 × 415 × 350mm


Product Introduction: