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Zhongshan Longde Electrical Co.ltd


Zhongshan Longde Electrical Co.ltd founded in 2005,which is engaged in the development and production of the temperature tuses and overheating protection products,is a strong,experienced and 
professional-oriented enterprise with mature technology and strict management.
 

 

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Zhongshan Longde Electrical Co.ltd

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Producing the high quality products with full efforts——This is the promise Longde gives to the users

Thermal Fuse

Thermal fuse, also called thermal fuse (national standard GB9816.1-2013), is a temperature-sensing loop cut-off device. Thermal fuses can sense the overheating generated during the abnormal operation of electrical and electronic products, thereby cutting off the circuit to avoid the occurrence of fire. Commonly used in: hair dryer, electric iron, rice cooker, electric stove, transformer, electric motor, water dispenser, coffee pot, etc...
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KSD Thermostat Series

When the electrical appliance is working normally, the bimetal is in a free state, and the contacts are in a closed/disconnected state. When the temperature reaches the operating temperature, the bimetal is heated to generate internal stress and act quickly, opening/closing the contacts and cutting/connecting the circuit. , so as to control the temperature. When the appliance cools down to the reset temperature, the contacts close/open automatically, returning to normal operation.

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9700 Thermostat Series

It is a thermostat with bimetal as a temperature sensing element. It has the characteristics of rapid action, accurate temperature control, large control current and long service life. It is widely used in various micro motors, induction cookers, air conditioner motors, small household appliances, etc. Temperature protection control.

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Producing the high quality products with full efforts——This is the promise Longde gives to the users

What is the temperature switch used to sense the temperature?


Many friends are very interested in how the sudden jump temperature control switch senses temperature! Since it is a snap-type temperature control switch, it must have its own temperature sensing system. If there is no good temperature sensing system, there is no way to predict the temperature, and it can be disconnected or contacted freely. The principle used by the thermostat is very simple. It is composed of bimetallic sheets. When the temperature reaches a certain height, it will be disconnected or touched together freely. This is also the most basic temperature sensing setting of the thermostat. The temperature sensing setting is also the most important point in the whole process. No matter what kind of electric heating equipment, it needs a good temperature sensing. Use can have a very big impact. Looking at the whole society, there are more and more fields of sudden jump temperature control switches, which are closely related to our lives and have long been inseparable from the connection. So far, there are many brands of temperature control switches. Maybe because of the different brands, their temperature sensing effects will be different, but their principles are still roughly the same, and there is almost no change. After all, they are all temperature switches. Control switch, the difference is definitely not big. The biggest difference is only a quality issue. Some temperature control switches are of very good quality, while others are a bit unsatisfactory, but this is not a very absolute thing! The sudden jump temperature control switch is also the core position of the electric heating equipment. We will use a simple water dispenser for comparison. If there is a problem with the temperature control switch of the water dispenser, it will be very troublesome for us to drink water. The temperature control switch of the water dispenser may be slightly different from the temperature control switch of other electric heating equipment. After all, most of the water dispensers have buttons, which are not automatic. And some temperature control switches are automatic temperature sensing, there are still some small differences between them, but the difference is not very big.   If we want to buy temperature switches, we should choose some trusted brands as much as possible, which will also reduce a lot of risks for shopping. The important thing is that good quality temperature control switches can ensure the durability of electric heating equipment. This fully shows that when choosing a temperature control switch, you must choose those with good quality, after all, the temperature sensing system they rely on is also a bimetallic sheet. If the temperature sensing system itself is not set strong enough, then the use time will be relatively reduced, which is also a problem that we should pay attention to when purchasing temperature control switches. What temperature does the temperature control switch rely on? What they rely on is the bimetal in it

2020-07-15

How many control modes does the electronic thermostat have


There are generally two control methods; one is controlled by the temperature change of the object to be cooled, mostly using a vapor pressure temperature controller, and the other is controlled by the temperature difference of the object to be cooled, mostly using an electronic temperature controller. controller. Thermostats are divided into: Mechanical type is divided into: vapor pressure thermostat, liquid expansion thermostat, gas adsorption thermostat, metal expansion thermostat. Among them, the vapor pressure thermostat is divided into: inflatable type, liquid-gas mixed type and liquid-filled type. The mechanical type of household air conditioner is mainly based on this type of thermostat. Electronic type is divided into: resistance thermostat and thermocouple thermostat. The role of the circuit system: The function of the air conditioner circuit system is to control the normal and multi-functional operation of the air conditioner, and to protect the normal operation of the compressor and fan motor. The main components of the circuit system are: thermostat, thermal protector, main control switch, running capacitor, fan motor running capacitor, etc. are fixed in the control box. The picture on the left is the electrical wiring diagram of the single cooling air conditioner. The role of the temperature controller is only to control the start and stop of the compressor. working principle steam pressure The action of the bellows acts on the spring, and the spring force of the spring is controlled by the knob on the control panel. The capillary is placed at the air outlet of the air conditioner indoors and responds to the temperature of the indoor circulating return air. When the room temperature rises to the set temperature, the temperature-sensing agent gas in the capillary tube and the bellows expands, making the bellows stretch and overcoming the elastic force of the spring to turn on the switch contacts. At this time, the compressor runs and the system cools down until room temperature. When the temperature drops to the set temperature again, the gas of the temperature sensing package shrinks, the bellows shrinks and acts together with the spring, and the switch is placed in the off position to cut off the motor circuit of the compressor. This action is repeated to achieve the purpose of controlling the room temperature. Electronic temperature controller The electronic temperature controller (resistance type) is measured by the method of resistance temperature sensing. Generally, platinum wire, copper wire, tungsten wire and semiconductor (thermistor, etc.) are used as temperature measuring resistors. These resistors have their own advantages and accuracy. point. Most of the sensors of household air conditioners are of thermistor type. The thermistor thermostat is made according to the principle of Wheatstone bridge, (left picture) is a Wheatstone bridge. Connect the power supply E at both ends of BD. According to Kirchhoff's law, when the resistance of the bridge is R1×R4=R2×R3, the potentials of A and C are equal, and no current flows between the output terminals A and C. , The size of the resistance R1 of the thermistor changes with the rise or fall of the surrounding temperature, so that the balance is destroyed, and there is an output current between AC. Therefore, when composing a thermostat, it is easy to change the temperature adjustment range and operating temperature by selecting an appropriate thermistor Metal expansion thermostat: According to the principle of thermal expansion and contraction of objects. Thermal expansion and contraction are common to objects, but different objects have different degrees of thermal expansion and contraction. The two sides of the double gold piece are conductors of different materials. Under the changing temperature, the double gold piece is bent due to the different degree of expansion and contraction. When it touches the set contact or switch, the set circuit (protection) starts to work. Thermostat switch, thermostat, thermal protector

2020-07-15

Longde Electric teaches you to use the thermostat correctly


There are more and more families using electric heating systems, and how to save energy has become a problem that many people pay attention to. In addition to good house insulation, temperature control is one of the keys to energy saving. Some users who have installed electric heating will always turn on the thermostat when needed, and turn off the thermostat when they go out, thinking that this will save electricity. In fact, this will not only save energy, but will consume more energy. So how to use the thermostat to achieve real energy saving? Let the editor of Longde Electric take everyone to learn.   1. Save energy when you hold a meeting right away? Turn on the thermostat when you need it and turn it off when you go out, which consumes energy. The electric heating system is a low-temperature operation system with good heat storage type. It takes a certain amount of time to make the room temperature reach the set temperature after the system is turned on, and the indoor temperature will not drop rapidly after the system is turned off. It also takes a longer time for the temperature to rise again. Frequent switching not only fails to save energy, but also increases the operating cost of the heating system. For rooms that are not frequently used, the temperature can be lowered by a few degrees through the thermostat. When you leave the house for a long time, you only need to lower the temperature of the thermostat by a few degrees. You can choose to turn off the system when you don’t live for a long time or leave for a long time. , but it should be noted that if there is equipment in the room that is afraid of freezing, it should be turned on to a certain temperature to prevent the equipment or pipes from freezing.   2. Does the thermostat set the high temperature to heat up quickly? Some users feel that the room temperature is low, and they need to quickly heat up to set the temperature of the thermostat to the highest, which is also wrong. The heating time of the room temperature depends on the indoor and outdoor temperature difference and the installed power per unit area of ​​the room. Under the condition that the installation power and the temperature difference between indoor and outdoor are certain, no matter how many degrees are set, the time for the room to rise to the temperature you need is the same. If the room is now 16 degrees, and you want the room to heat up to 18 degrees, in this case, set the room temperature to 18 degrees or 20 degrees, 25 degrees, and the time it takes to heat up to 18 degrees is the same. Set as many degrees as needed, or use an intelligent thermostat, the thermostat can automatically calculate the advance opening time of the thermostat.

2020-07-15