The temperature control skills of the electric heater of the air duct have also been greatly advanced

Electric heater is commonly used in industrial production and scientific research. Heating and temperature are not available. During heating, various kinds of heating, memory and temperature control are often needed. With the development of computer application skills, the temperature control skills of electric heaters have also been greatly advanced. It can be roughly divided into two major categories.

The first type of plan is shown. It is actually from the normal appearance of the appearance, that is, the emblem system instead of the external system of the conditioning Road, can be said that this is a hybrid system. Its main advantage is that it is easy to connect with the appearance system, and it is easy to complete the switch between the table system and the Huizhou machine system, which is beneficial for the transformation of the appearance system in a short time. However, there are obvious defects in such plans for electric heaters. The first is the equipment used more system clutter. The cost is higher; secondly, because transform multi link output channel (especially after the analog conversion, so nonlinear interference is more serious, and the difference of energy control accuracy is low; third, system reliability is poor. The second type of plan is shown. In this kind of plan, the output terminal removes the links of D/A transform, voltage signal expansion and power frequency and high voltage pulse signal transformation. It directly controls the on-off of solid state relay with TTL level pulse quantity signal, and controls the interruption of electric heater by solid state relay. It can be said that this plan basically overcomes the defect of the first plan, give full play to the advantages of computer skills. The electric heater which can not only considerably reduce the cost, and can greatly improve the control precision (from room temperature to 720 DEG C, control precision is better than 0.5 DEG C). In addition, its anti-interference function and reliability are superior to the first class plan.

In addition to the common sense that everyone knows, there are:

The environmental conditions of the electric heater are: the air relative humidity is not more than 95%, and there is no explosive or corrosive substance or gas in the environment. The operating voltage can not be greater than 1.1 times the rated voltage, and the insulation resistance should not be less than 1M Omega.

The electric heating tube in the electric heater should be positioned and fixed. The effective heating area should be immersed in liquid or metal solid. The phenomenon of empty burning is forbidden. This will damage the electric heater.

If there is scale or carbon deposition on the surface of the pipe, it should be cleaned up immediately, so as not to affect the heat dissipation of the electric heating tube, thereby affecting the service life of the electric heater.

The fusible metal, or solid salt, alkali, asphalt, paraffin and other heating, should use low voltage. When the medium is melted, the voltage is then raised to the rated voltage.

When heating the air, the elements should be arranged uniformly, so that the components can have good heat dissipation conditions and make the air fully heated.

The wiring part should be outside the insulation layer, and to avoid the damp. When the wiring screw is fastened, it should be avoided too hard.