Obviously the PhotoRelays differ from the conventional electro-mechanical relays.
PhotoRelays are classified to semiconductor relays that have no moving contact, therefore they are superior to conventional electro-mechanical relays in life-expectance and reliability of contacts, operation speed, and their sizes.
But they also distinguish themselves from other switching solutions that utilize photo-couplers, photo-transistors etc.. PhotoRelays have MOSFET for output, therefore they are the most suitable devices for small analog signal switching.
|Compared with Electro-Mechanical Relays |
have moving contact:
|Compared with SSR (Solid State Relays)|
have phototriac for output:
|●Longer lifetime (No limit on mechanical and electrical lifetime)|
●Higher-speed and high-frequency switching
●Higher sensitivity (less power consumption)
●Less contact problems such as arcs, bounce, and noise
●More resistant to vibration and impact
●No limitation for the mounting direction
|●Able to control miniature analog signal|
●Applicable to both AC/DC
●Less leakage current
●Lower offset voltage
●Various contact structures such as 2a, 4a, 1b, 2b, and 1a1b in addition to 1a