1. Official complete definition Reed relay is a kind of magnetic control electromagnetic relay which is composed of sealed reed tube as contact switch element and matched excitation coil. Two magnetic alloy reeds are sealed in a glass tube filled with inert protective gas to form a dry reed tube, and an excitation coil is wound outside the dry reed tube; the coil is electrified to generate a magnetic field to magnetize the reeds, and the contacts are attracted and connected by means of magnetic force; and after the coil is powered off, the reeds are automatically separated and disconnected by means of the elasticity of the reeds, so that the on-off control of a circuit is completed. 2. Disassemble the core points Core switch unit: reed switch The contact is completely sealed in the glass tube, and the inside is filled with nitrogen to isolate the air, so as to prevent oxidation, moisture and dust pollution. Drive mode: magnetic field driven There is no iron core, no armature, no external reset spring, and only the magnetic field of the coil controls the action of the reed. Working medium differentiation Different from the open mechanical contact of the conventional electromagnetic relay, it belongs to the sealed magnetic reed type weak current switching relay. 3. Simplify the popular definition (can be directly used for documentation/learning) The dry reed relay is composed of a dry reed tube and a driving coil, and the opening and closing of the sealed reed in the glass tube are controlled by the magnetic field of the coil, so that the dry reed relay is used for switching a micro electric signal.