Choice of contact load

Contact load refers to the bearing capacity of the contacts. The contacts of the 5v relay can withstand a certain voltage and current when switching. Therefore, when using a 5v relay, it should be considered that the voltage on the contact and the current passing through the contact cannot exceed the contact load capacity of the 5v relay. If it exceeds the load capacity, it will affect the normal use of the 5v relay, or even burn the contacts.

Selection of 5v relay coil power supply

This refers to whether the 5v relay coil uses direct current (DC) or alternating current (AC). Usually, beginners use electronic circuits in electronic production activities, and electronic circuits are often powered by DC power, so it is necessary to use a 5v relay with a coil of DC voltage.