Relay is an electrical control device that is an electrical device that causes a predetermined step change in the controlled output quantity in the electrical output circuit when the input quantity changes to meet the specified requirements. What are the reasons for the relay not to be disconnected? Let's take a look at the following:
1. The load current is greater than the rated switching current of the SSR, which will permanently short the relay. In this case, use a SSR with a large rated current.
2. At the ambient temperature where the relay is located, if the heat is not good, the output semiconductor device may be damaged. In this case, a larger or more effective heat sink should be used.
3. Line voltage transients cause the SSR output section to be punched through. In this case, use a higher rated SSR or provide additional transient protection circuitry.
4. The line voltage used is higher than the rated voltage of the SSR.