1, computer and electronic equipment voltage
The power structures of computers and electronic devices (such as televisions, copiers, fax machines, PLCs, etc.) are very similar, so their sensitivity to voltage sags is similar, and they are discussed here as a type.
The simplified structure of the power supply for computer and electronic equipment typically consists of a diode rectifier and a voltage regulator (DC/DC converter). The AC voltage is rectified by a rectifier to obtain a DC voltage of several hundred volts, which is then regulated by a voltage regulator to a DC voltage supply device of a voltage rating of 10V. If the voltage on the AC side is reduced, the DC side voltage of the rectifier will also decrease, but within a certain range of voltage variation, the voltage regulator can keep its output variation small and the device works normally. However, if the voltage on the DC side of the rectifier is too low and the output voltage of the voltage regulator can no longer maintain the specified value, an error will occur inside the digital electronic device or the computer power supply will trip.
2, adjustable speed drive
Adjustable-speed drives (ASD) are one of the most critical devices in an industrial process to control the speed, torque, acceleration and direction of rotation of the motor. It is very sensitive to voltage sag. When the voltage drops by 30%~40% for 120ms, the user's ASD stops running, and when the driving process is strict on the motor's speed and torque, the device will temporarily drop the voltage. More sensitive. The adjustable speed drive is powered by an AC power supply via a three-phase diode rectifier or a three-phase controlled rectifier. In general, the first method is more common in AC drives, and the second method is more common in DC drives and large AC drives. Due to the similar mechanism, only small and medium-sized AC drives powered by three-phase diode rectifiers are selected for discussion.
Most AC-driven three-phase AC voltages are rectified by a three-phase diode rectifier and filtered by a DC-side capacitor. Some DC sides of the drive may also be connected to an inductor. The rectified DC voltage is inverted by a voltage source inverter (VSC) into an AC voltage having a variable frequency and amplitude to the motor.
3, electromagnetic switch electromagnetic switch mainly has two types of AC contactor and relay, generally used for low-voltage industrial wiring and control motor starting. There is an electromagnetic coil, a movable iron core and a spring. The principle is that when current flows through the upper electromagnetic coil, the electromagnetic force generated by the upper iron core will attract the lower movable iron core, causing the normally open point (NO) core to close, and the normally closed point (NC) will leave because of the movable iron piece. Open the joint.
When the electromagnetic contact is subjected to voltage sag interference, the current flowing through the coil becomes smaller as the voltage becomes smaller. When the current becomes smaller, the generated magnetic force is insufficient to attract the movable iron core, which causes the electromagnetic switch to be industrially The controlled device malfunctions and even stops. Studies have shown that when the voltage is less than 50% and the duration is more than 20ms, the contactor will trip; some studies have shown that when the voltage is lower than 70%, the contactor may trip.
4, lighting equipment Most lighting lights only flash or temporarily darken when the voltage sag occurs, will not cause serious consequences. The lighting equipment that is mainly discussed here is a high-intensity discharge (HID), such as a mercury lamp, a metal halide lamp, a high-pressure sodium lamp, and the like. HID not only has high luminous efficiency, but also has higher luminous quality, longer life and high economic efficiency compared with fluorescent lamps. From the above advantages, it can be seen that HID will become more and more popular in the application of future lighting technology and will occupy an important position.
HID is an arc discharge lamp, and the lamp current changes greatly during illumination. Therefore, a ballast is needed to stabilize the current and stabilize the light emitted by the bulb.
HID ballasts can be divided into electronic and electromagnetic (traditional). Electronic ballasts have the advantages of small size, high efficiency and long life. Currently, electromagnetic ballasts have a tendency to be replaced by electronic ballasts.
5, mechanical device
In general, for finishing robots or complex machines used for cutting, drilling and metal processing, any change in voltage can affect the quality of the part being machined. Another reason that mechanical devices are sensitive to voltage changes is due to safety considerations. Automatic devices typically require very smooth voltages for normal safe operation, and any voltage fluctuations, especially voltage dips, can cause abnormal operation of automated devices or complex machinery. Therefore, this type of mechanical device is usually set to trip at 90% of rated voltage.
"Non-burning, nicotine for users, low tar content. As the heating temperature (below 500℃) is lower than the combustion temperature of traditional cigarettes (600-900℃), the harmful components produced by tobacco high-temperature combustion pyrolysis and thermal synthesis are reduced, and the release amount of side-flow smoke and environmental smoke (second-hand smoke) is also greatly reduced."
Heating non - combustion products are electronic devices containing tobacco. When you heat them, they produce a nicotine-containing vapor that you can inhale.
They are different from traditional cigarettes and work by heating tobacco to a very low temperature. Tobacco is heated to 350 ° C in a heat-incombustible device, while traditional cigarettes burn at up to 900 ° C.
Still, the temperature at which non-combustion products are heated is high enough to vaporize and inhale harmful chemicals.
Although both are electronic devices, heated non-combustible products are also different from e-cigarettes or steam devices. These usually use chemical liquids and do not necessarily contain nicotine. E-cigarettes tend to heat liquids to around 250 degrees Celsius to produce vapor.
Hnb Device Oem,Hnb Device Patent,Hnb Device,Hnb Device For Sale
Shenzhen MASON VAP Technology Co., Ltd. , https://www.e-cigarettefactory.com