(1) First understand the necessary conditions for relay selection

1) The supply voltage of the control circuit, the maximum current that can be supplied;

2) The voltage and current in the circuit to be controlled;

3) How many groups of contacts are needed in the controlled circuit, and in what form. When selecting a relay, the supply voltage of the general control circuit can be used as the basis for selection. The control circuit should be able to provide sufficient operating current to the relay, otherwise the relay suction is unstable.

(2) After consulting the relevant information to determine the conditions of use, you can look up the relevant information to find out the model and specification number of the required relay. If you already have a relay on hand, you can check whether it is available based on the information. Finally, consider whether the size is suitable.

(3) Pay attention to the volume of the appliance. If it is used for general appliances, in addition to considering the volume of the chassis, small relays mainly consider the circuit board mounting layout. For small appliances, such as toys, remote control devices should be selected ultra-small relay products.