Solid State Relay, 3 phase, load current 40A, DC-AC, zero-cross switch, built-in RC, optical isolation between input and out circuit, with LED indicator, especially suitable for frequent switching occasion and some harsh environments of corrosion, moisture, dust, etc.
|On-state voltage drop
|Off-state leakage current
||2500V AC (1min)
||500МΩ with 500V DC
||Fan needed for cooling
Tips: Thermal design and radiator selection of SSRs
There is certain internal power dissipation in SSRs’ operation. The dissipation value is mainly determined by product of output voltage drop and load current, embodied in the form of heat radiation. The quality of heat dissipation directly affects maximum load current of SSRs and maximum allowable temperature of the working environment and it is one of the important factors that affect the reliable operation of SSRs. Therefore, we should pay attention to thermal design and radiator selection so that SSRs may work reliably and failure of and damages caused by poor heat dissipation to SSRs can be avoided.
In general, SSRs, whose output current is less than 5A, use natural convection air enough to achieve the purpose of cooling, but when installed, SSRs need a good convection environment and the space between each SSR should not be less than the width of a SSR. It is essential for those SSRs with a load current greater than 10 A to use suitable radiators, even forced air cooling (air speed at 6 m/s) or water-cooling if necessary. The good heat dissipation condition is very important for SSRs’ reliable work.