1, working principle and characteristics of relay:
Relay is an electronic control device, which has a control system (also called input loop) and a controlled system (also called output loop). Usually used in automatic control circuits, it is actually an "automatic switch" that controls a larger current with a smaller current. Therefore, it plays the role of automatic adjustment, safety protection and conversion circuit in the circuit. 2. Technical parameters of main products of relay:
(1), rated working voltage:
Refers to the voltage required by the coil when the relay works normally. Depending on the model of the relay, it can be AC voltage or DC voltage.
(2) DC resistance movement:
Refers to the DC resistance of the coil in the relay, which can be measured by multimeter.
(3), pull-in current:
Refers to the minimum current that relay can produce pull-in action. In normal use, the given current must be slightly larger than the pull-in current before the relay can work stably. In general, the working voltage applied to the coil should not exceed 1.5 times of the rated working voltage, otherwise a large current will be generated and the coil will be burned.
(4), release current:
Refers to the maximum current that the relay produces release action. When the current in the pull-in state of the relay decreases to a certain extent, the relay will return to the non-energized release state. At this time, the current is much less than the pull-in current.
(5), contact switching voltage and current:
Refers to the voltage and current allowed by the relay to the load. It determines that the relay can control the voltage and current, and cannot exceed this value when it is used, otherwise it will easily damage the contacts of the relay.