1、The influence of the use of environmental temperature
Solid state relay load capacity by the ambient temperature and its own temperature rise, device use process, should ensure that it has good heat dissipation conditions, rated operating current in more than 10A products should be equipped with a heat sink, more than 100A products should be equipped with a heat sink plus fan strong cooling device should pay attention to the bottom of the relay and good contact with the heat sink and consider coating the appropriate amount of thermal grease to achieve the best heat dissipation effect.
If the relay temporarily work in a high temperature state 40 ℃ ~ 80 ℃), the user can provide the maximum output current and ambient temperature curve data according to the manufacturer, consider reducing the use to ensure normal work.
2、Over-current and over-voltage protection measures
Relay use, due to overcurrent and load short circuit will cause permanent damage to the internal output of solid state relay silicon, can be considered in the control circuit to add a fast fuse and air switch to maintain the type; can also be connected to the relay output RC absorption circuit and voltage sensitive resistor to achieve output maintenance. The principle of selection is to choose 500V-600V varistor for 220V, and 800V-900V varistor for 380V.
3、Relay input circuit signal
When using the input voltage is too high or input current is too large beyond its rated parameters, consider connecting a voltage divider resistor in series with the input terminal or shunt resistor in parallel with the input port, so that the input signal does not exceed its rated parameter value.
4, the specific use, control signal and load power requirements for stable, fluctuations should not be greater than 10% or should take voltage stabilization measures.
5, the device should be used away from electromagnetic interference, radio frequency interference sources, to prevent the relay misoperation out of control.
6, solid state relay open circuit and load voltage, there will be a certain leakage current at the output, the use or design should be noted.
7, solid state relay failure replacement, should try to use the prototype or technical parameters of the exact same product, in order to match the original application line, to ensure the reliable work of the system.
The above is an introduction to the common failures and maintenance of solid state relays. Solid state relays have been widely used in computer peripheral interface equipment, thermostat systems, temperature regulation, electric furnace heating control, motor control, CNC machinery, remote control systems, industrial automation devices; signal lights, dimming, blinkers, lighting stage lighting control systems; instruments, medical equipment, copiers, automatic washing machines; automatic fire fighting, security systems, and as power factor compensation of the power capacitor of the power grid Switching switch and so on, in addition in the chemical industry, coal mines and other need explosion-proof, moisture-proof, anti-corrosion occasions are used in large quantities.
