La long and windy
Simple point conversion isolation signal and more than a few contacts
Electromagnetic relay is generally composed of iron core, coil, armature, contact reed and so on. As long as the coil at both ends with a certain voltage, the coil will flow through a certain current, resulting in electromagnetic effects, the armature will be attracted by the role of electromagnetic force to overcome the return of the spring to pull the iron core, Moves the contact with the static contact (normally open contact). When the coil is powered off, the electromagnetic force will disappear, the armature will return to the original position of the spring, so that the movable contact with the original static contact (normally closed contact) release. So that pull, release, so as to achieve the circuit in the conduction, cut off the purpose. For the relay "normally open, normally closed" contacts, it can be distinguished: relay coil is not in power when the state of the static contact, known as the "normally open contact"; in the state of the static contact As "normally closed contact".
The relay is an electronic control device, it has a control system (also known as the input circuit) and the control system (also known as the output circuit), usually used in automatic control circuit, it is actually a small current to control the larger A "automatic switch" of the current. So in the circuit plays an automatic adjustment, security protection, conversion circuit and so on.
