Instead of using a coil, packaged solid-state relays(SSR) use power semiconductor devices such as thyristors and transistors, which provide a much faster switching speed than the mechanical relays. The Grove - Solid State Relay V2 is based on the high-quality G3MC202P module, which allows you to use a 5VDC to control MAX. 240VAC. With the help of the Grove interface, it becomes very convenient to use the SSR with your Arduino.
Features
Advantages over mechanical relays:
Solid-state relays have much faster switching speeds compared with electromechanical relays, and have no physical contacts to wear out.
Totally silent operation.
No physical contacts means no sparking, allows it to be used in explosive environments, where it is critical that no spark is generated during switching.
Increased lifetime, even if it is activated many times, as there are no moving parts to wear and no contacts to pit or build up carbon.
Compact, thin-profile SSR of monoblock construction with an all-in-one lead frame incorporates a PCB, terminals and heat sink, which is much smaller than mechanical relays, and can integrate more channels
Disadvantages:
When closed, higher resistance (generating heat), and increased electrical noise.
When open, lower resistance, and reverse leakage current.
Only works for AC loads.
Typical Applications
Operations that require low-latency switching, e.g. stage light control.
Devices that require high stability, e.g. medical devices, traffic signals.
Situations that require explosion-proof, anticorrosion, moisture-proof, e.g. coal, chemical industries.