Relay construction and working principle - Solutions - Huaqiang Electronic Network

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Electromagnetic relays are a common type of relay, and Type 4098 ultra-small relays are the most widely used. Figure 1 is a schematic view showing the structure of such a relay.

The working principle of the relay is that when the relay coil is energized, the iron core in the coil generates a strong electromagnetic force, and the armature is driven to move the reed, so that the contacts 1, 2 are disconnected, and 1, 3 are turned on. When the coil is de-energized, the spring resets the reed, causing contacts 1, 2 to be turned on, and 1, 3 to open. We can use the relay to achieve some control by connecting the circuit to be controlled between the contacts 1, 2 (1, 2 is called a normally closed contact) or between the contacts 1, 3 (called a normally open contact). the goal of.

Figure 1 4098 type relay

The 4098 relay coil has various operating voltages of 3 volts, 6 volts, 9 volts, and 12 volts. The current passing through the coil during pull-in is about 50 mA, and the current allowed between the contacts can reach 1 amp (250 volts).