Tag: what is

A magnetic stirrer also known as magnetic mixer is a kind of laboratory equipment which is mainly used for stirring or heating stirring in low-viscosity liquid or solid-liquid mixing experiments. A rotating magnetic field is generated under the container plate, and the principle of homosexual repulsion and heterosexual attraction is used to push the magnetic stirring rod in the container to rotate rapidly, thereby achieving the purpose of stirring. The plate usually has a heating function to meet more experimental needs.

Hipot tester, also called dielectric strength tester, is used to carry out the test of applying a specified AC or DC high voltage between the live part and the non-live part of the electric appliance to check the hipot of the insulating material of the electric appliance. In long-term work, electrical appliances must not only bear the effect of rated working voltage, but also bear the effect of overvoltage that is higher than the rated working voltage for a short time during operation(The overvoltage value may be several times higher than the rated working voltage value). Under the action of these voltages, the internal structure of electrical insulating materials will change. When the overvoltage intensity reaches a certain value, it will cause the insulation breakdown of the material. The electrical appliances will not operate normally, and the operator may get an electric shock, endangering personal safety. The main electrical safety test indicators include AC/DC hipot, insulation resistance, leakage current, ground resistance, etc. AC/DC hipot tester is used to test the electrical safety performance of the product under actual working conditions, so it is one of the important instruments for testing the electrical safety performance of the equipment.

In recent years, a new type of vacuum pump that can be achieved from atmospheric pressure to high vacuum with only one pump has been developed, but generally speaking, for obtaining high vacuum, ultra-high vacuum and extremely high vacuum, multiple vacuum pumps are connected in series to complete the pumping task. Thus, knowing the type of pumps properly is important for user to choose affordable and suitable vacuum pump.

Gas detector is an instrument for detecting the concentration of gas leakage, including portable gas detector, hand-held gas detector, fixed gas detector, online gas detector, etc. It mainly uses a gas sensor to detect the types of gases present in the environment, and the gas sensor is a sensor used to detect the composition and content of the gas.

An automatic screw feeder is an automatic device that replaces human hands to take, put and tighten the screws by automatic mechanism, which mainly applies for automatic assembly, such as producing car components, computers, display screens, motors, lamps and lanterns, mobile phones, printers, circuit boards and batteries. It can extremely improve production efficiency and reliability as well as reduce production costs. 

Automatic screw feeders are divided into the handheld automatic screw feeder and the fully automatic screw feeder. 

The principle of three-phase isolation transformer basically adopts the principle of electromagnetic induction. It is safe to use a three-phase isolation transformer, which is generally used as a maintenance power supply. The isolation transformer is commonly 1:1 transformer, but it has different specifications. Three-phase isolation transformers are used for changing voltage, lighting, power supply and rectifying power supply, widely applied to industrial and mining enterprises, power plants, airports, high-rise buildings, subways and other places with high fire safety requirements.

Isolation transformer is the transformer with electrical isolation between the input winding and the output winding. Isolation transformer is used to avoid users accidentally touching the charged body at the same time. Isolation transformer, whose transformer ratio is usually 1:1, is a special transformer with high insulation strength between the primary winding and secondary winding to isolate different potential to suppress common mode interference. The main function of the step-up & step-down isolation transformer is to completely insulate the primary side and the secondary side, and also to isolate the loop. In addition, the high frequency loss of the iron core is used to suppress the high frequency clutter into the control loop. 

Industrial water chiller is a kind of water cooling equipment, which can provide constant temperature, constant current and constant pressure. The principle of the chiller is to inject a certain amount of water into the internal water tank of the machine, cool the water through the cooling system of the chiller, and then the water pump inside the machine will inject the low-temperature frozen water into the equipment to be cooled, the frozen water will take away the heat inside the machine, and return the high-temperature hot water to the water tank again for cooling, so as to achieve the function of cooling the equipment by circulating and exchanging cooling.

What is the principle of the chemical element analysis instrument?
Chemical analysis instrument is mainly used for in-site measurement of elements in metal materials in the military industry, aerospace, iron and steel, petrochemical, power, pharmaceutical and other fields, it's an indispensable tool for rapid identification of materials in the industrial and military manufacturing fields accompanying the rise of the world economy.
Principle of chemical element analysis instrument.

What is the fiber optic sensor

Fiber optic sensor is a medium that transmits light waves by the principle of complete internal reflection of light, it consists of a core and cladding with a high refractive index. The refractive index of the cladding is smaller than that of the core, and its diameter is about 0.1mm～0.2mm. When the light penetrates into the fiber core through the end face and reaching the interface with the cladding, the light is reflected back to the fiber core due to the complete internal reflection of the light. After constant reflection, the light propagates along the fiber core and has only a slight attenuation. In actual detection process, the fiber optic sensor guides the light emitted by the transmitter to the detection point through light-guide fiber, and then guides the detected optical signal to the receiver through light-guide fiber, the detection is thereof realized. According to the different manner of execution, the fiber optic sensor can also be divided into various types, such as opposite type, diffuse reflectance type. Fiber optic sensor can detect objects in the far area. Due to the fiber loss and fiber dispersion, the intermediate amplifier shall be set at a proper position for long-distance fiber transmission system, so as to process and amplify the attenuated and distorted light pulse signals.

Three-phase imbalance means that inconsistent amplitude of three-phase current (or voltage) in electrical power system and that amplitude difference surpasses the specified range.
Unbalanced current of transformer refers to current difference of three-phase transformer windings. The current difference is mainly caused by different three-phase load. Asymmetry of load gives rise to asymmetry of three-phase current which flow through transformer. And current asymmetry causes asymmetry of three-phase impedance drop of transformer, thus three-phase voltage of secondary side is asymmetric, which will do harm to transformer and electric equipment.