AC contactor is widely used in low-voltage circuit, it is a kind of safe use, convenient control, large amount and a wide range of industrial necessities.China is now generally used in 40A and above large and medium capacity of AC contactors should be more than 100 million meters, its operating electromagnetic system in the suction of active power consumption between 8w-100w.The reactive power consumed is between dozens of bills and hundreds of bills.The distribution of active power consumed is roughly 65%~75% iron core, short circuit ring 25%~30%, 3%~5% coil.In view of the problem of large power consumption in the operation of AC contactors, as early as 1981, the national release document no. 56 pointed out that the power saving measures of AC contactors should be implemented.After long-term research, some energy saving achievements have been achieved, but the structure of traditional contactors has been greatly reformed, the process is complicated, and the production cost is increased.The finished product is expensive, or the use range is small, or not in line with people’s use habits, and some also affect its reliability to varying degrees, which may be the main reason why the contactor energy-saving products have not been widely accepted by the market.
1 Several common energy saving methods of AC contactors in the market and their advantages and disadvantages:
Working principle of newly developed energy saving device for contactor
The energy saving device has a free tripping mechanism, using the principle of crank link lock (unlock only 0.15N-0.3N force), the mechanism firmly stuck, make the contact electromagnet can maintain all contact groups without energy consumption, unlock the purpose of energy saving; because it is mechanical lock, its life can not be too high, about 35,000 times, so it is used in continuous operation occasions, such as control fan, pump and capacitor compensation cabinet.The working principle is as follows:
The energy saving device is connected to the contactor, including housing, starter rod, free tripping mechanism, normally closed micro switch, rod, energy saving coil and electromagnetic buckle assembly.Start rod move with the contact of the contactor, using the crank linkage by the lock principle, the mechanism firmly stuck, micropower electromagnetic buckle component core suction extrusion micro switch, make often closed micro switch contact often closed to often open contact, the coil of the contactor power, the electromagnet without energy consumption can still keep all the working state of the contact group, current only from the energy saving coil through.When a control signal is suddenly applied or a power grid suddenly fails, the micropower consumption electromagnetic tripping component pushes the link to disconnect the free tripping mechanism, and the starting lever returns to the starting position under the contactor counterforce spring.Because the micro-power consumption electromagnetic unbuckle component required to unlock the force is very small can make the electromagnet unlock, to achieve the purpose of energy saving.
Figure 1 is a profile diagram of contactor special energy saving device and contactor or relay.
FIG. 2 is a circuit connection diagram for a special energy saving device and contactor or relay.
3. Characteristics of the newly developed special energy-saving device for contactors
3.1 No manual reset: the power grid suddenly blackout, the main circuit will be automatically disconnected, without manual reset;
3.2 Mechanical interlocking function ensures the safety and reliability of the products
The device is also equipped with mechanical interlocking function, if the lock does not firmly jam the mechanism, the coil in the contactor will not power off, so that the main contact continues to keep closed, so if the device cannot be reliably put into use or damaged, will not affect the normal use of the contactor of the original, but the product is no longer energy saving.
3.3 No auxiliary power supply is required
As shown in Figure 3, the energy-saving device does not need auxiliary power supply, together with the main power supply, and can also add a stop button to remotely control the contactor, with no safety risks.
3.4 Plug and Play
Energy-saving device is directly hung on the contactor products, the old contactor or relay can be used without modification; easy installation, wide use range.
3.5 High efficiency and energy saving of more than 90%
When use with the device, the AC contact core does not produce periodic absorption, no vibration, so there is no noise, can greatly reduce energy consumption, simple maintenance, effectively reduce the operating cost.
3.6 Do not affect the original contactor function, but also other functional auxiliary contacts can be added
Do not occupy the original auxiliary contact, but also according to the need, the design to add auxiliary contact, delay function and capacitor special energy saving device, so that it has different functions.
3.7 Can extend the anti-sway electric function
This device has a certain delay function, successfully solve the problem of “shaking electricity”.At present, under the same conditions, the contact life of energy-saving AC contactor and traditional AC contactor is increased by 3-5 times, reducing the operation and maintenance cost.
3.8 Wide voltage operating range
Wide voltage suction 0.8-1.1US, release voltage 20%~75%US, AC-DC contactor universal.
Post time: Apr-22-2022
