- Mar 22, 2012 -
The function and maintenance key points of the crane's time relay
The function of time relay
Crane time relay is the role played by adding or removing action, the input signal, using the electromagnetic principle and mechanical action of the original, or close the open limit output delay control circuit of the crane can be used for precise control of parts of equipment action time.
Because this relay has the function of delay only when the power is broken, it is also called the power off time delay time relay. The time delay of the controller can be controlled. The JT3 series DC electromagnetic time relay is generally used for the crane control panel.
The JT3 series of DC time relay components include coils, moving static centers, fine tuning springs, and static contacts and so on. Its delay function is determined by the slow decay rate of magnetic flux in the magnetic circuit. The relay is equipped with a static iron core, metal damping sleeve, when the coil power, the damping sleeve generates induction current, because the current existence of the iron core flux attenuation slowed, but after the power of moving core relay in after a certain period of time delay in the release, this is the function of time delay relay.
Two. Installation and maintenance of time relay
1, no breakage, deformation and dirt appeared on the surface of the time relay.
2. The time relay in the work has no overheating or abnormal sound.
3. The setting value of the time relay should be basically the same as the action value, the action of the contact is rapid, and the delay error of the relay is controlled within 10%.
4, the usual way to adjust the time delay effect of time relay is to change the thickness of non-magnetic shim. In addition, it can also adjust the way of armature spring pull to adjust the delay time evenly.
5. Ensure that the resistance at both ends of the auxiliary contact of the time relay is about zero.
6. In the power simulation and manual simulation test, the action of the time relay is correct and the delay is accurate.
7. The time relay is not suitable for the place where the voltage is lower than its rated voltage. In addition, the change of temperature has a certain influence on the delay precision of the relay.