Time relay selection attention points

As the most common type of relay, time relay plays an important role in electrical control systems. The principle is to complete the control of the line by performing a certain period of time on the input signal - that is, "delay action", and then continuing to execute the command of the input model.

First, a brief introduction to the classification of the time relay: if only the principle of action is considered. Time relays can be mainly divided into the following categories: transistor type, such as JS20 transistor relay; electronic type, such as JSS1 electronic relay; DC electromagnetic type. In general, the use of air is the most common, and the performance of electric and transistor type is better, but the price is relatively high.

The following mainly introduces the following points for the selection of time relays:

In general, the most important factors to consider when selecting a time relay are the delay range, delay type, delay accuracy, and operating conditions. Of course, some basic factors will not be neglected, such as the rated working voltage and the rated working current.

The time relay has the rated operating voltage Un and the rated operating current In of the contacts in the corresponding use category, characterizing the ability of the relay contacts to switch circuits. When selected, the maximum operating voltage of the relay can be the rated insulation voltage Ui of the relay. The maximum operating current of the relay should generally be less than the rated heating current of the relay. Usually a relay specifies several rated operating voltages and lists the corresponding rated operating current (the control power can also be listed). This also determines the entire flow of the time relay. The next step is to use the choice of category, such as for communication or DC. Precautions for coil continuity must also be considered. Finally, there are some specific conditions of use restrictions. Such as the surrounding environment, temperature, pollution level, altitude, vibration and other factors. The involved here is also very complicated, you can see the instruction manual of the corresponding time relay product.

For the product, the most important and most important purpose is to be stable and reliable, while ensuring its accuracy. The selection of the time relay mentioned above is only very shallow. In the case of selection, it is also necessary to analyze the specific problems in combination with the actual situation. But the most important thing is to understand what you really need.

Time relay selection:

For occasions where the delay requirement is not high, electromagnetic damping type or air damping type time relay is generally used; for high delay requirements, motor type or electronic time relay can be selected.

For electromagnetic damping and air damped time relays, the coil current type and voltage level should be the same as the control circuit;

For motor and electronic time relays, the current type and voltage level of the power supply should be the same as the control circuit.

According to the requirements of the control circuit, select the power-on delay type or power-off delay type and the contact delay type (whether it is delayed or delayed) and the quantity.

Finally, consider whether the operating frequency meets the requirements.

The new series of time relay products JS14A series, JS20 series semiconductor time relay, JS14P series digital semiconductor relays have the advantages of small size, high delay precision, long life, stable and reliable operation, convenient installation, large contact output capacity and full product specifications. Advantages, widely used in electric drag, sequence control and automatic control of various production processes.