- May 23, 2018 -
The function of Crane time relay
The function of the crane time relay is to play the control action. By adding or removing the input signal, using the electromagnetic principle and the principle of mechanical action, the control line corresponding to the time delay or the time limit closed disconnection can be used to accurately control the action time between the parts and equipment of the crane.
Because this kind of relay has the function of delay only when the power is cut off, it is also known as the power off time delay relay. The time delay of the controller can be controlled. Generally used for crane control panel is the JT3 series DC electromagnetic time relay.
The components of the JT3 series DC time relay include coil, dynamic center, fine-tuning spring, dynamic and static contact and so on. The delay function is determined by the slow decay of magnetic flux in the magnetic circuit. A metal damping sleeve is installed at the static iron core of the relay. When the coil is broken, the induction current is produced in the damping sleeve. Because the current exists, the flux attenuation speed of the iron heart is slowed down, and the dynamic core of the relay will be released after a certain time delay. This is the delay of the time relay. Time function.
Installation and maintenance of time relay
1, the surface of the time relay appear no damage deformation and dirty.
2. The time relay in operation is not overheated or abnormal.
3, the setting value of time relay should be basically the same as the action value, the contact action is fast, and the delay error of relay is controlled within 10%.
4. The usual method of adjusting the time delay effect of time relay is to change the thickness of the nonmagnetic gasket. In addition, the time delay time can be adjusted evenly by adjusting the armature spring tension.
5, make sure that the resistance of the two ends of the auxiliary contacts is zero.
6. In the power analogue and manual simulation tests, the time relay acts correctly and accurately.
7. Time relay is not suitable for places where voltage is below its rated voltage. In addition, temperature changes have a certain effect on the delay accuracy of relay.