Safety Relay Working Principle

Safety relay can be classified into electromagnetic safety relay, thermal reed relay and solid-state relay. The working principle of safety relays can also be roughly divided into three types. Safety relay is composed of several relays and circuits, so as to supplement each other's abnormal defects and achieve the complete function of relay with correct and low faulty operation, so as to make the error and failure value become lower, thus reaching higher safety factor. Therefore, multiple safety relays should be designed to protect different grades of machinery. It is used to mainly protect the mechanical operators who perform operation under different levels of risk.

This kind of relay has the safety protection function and use low pressure to control high voltage, which also can be considered to protect the personal safety with just one safety relay, which can avoid the electric arc danger when contacting the high pressure switch. It is a relay that uses a low-voltage electrical switch to control a high-voltage switch. In other words, the low-voltage magnetic core pulls in the high-voltage switch.

The so-called "safety relay" is not a "non-fault relay". It has a forced guiding contact structure and can ensure safety in case of contact melting. Where is the safety relay used?

• When the emergency stopping is released, the machine cannot start suddenly.
• When failure of the machine safety circuit occurs, the power supply of machine can be stopped.
• When the safety circuit fails, the machine cannot start the safe input such as safety switch and light screen.