A solid state relay switches a load electronically, with no moving contacts, which gives silent, wear-free operation even at high switching frequencies. SSRs are used for temperature control of heating elements in plastics machines, ovens and packaging lines, and for frequent switching of motors, lamps and valves. SCN supplies solid state relays from celduc and DC motor reversers from Nominal Controls.<\/p>\n
Under 2 and 3 phase<\/a> you find celduc SOB and SOBR relays that switch two phases from 2\u00d715 A to 2\u00d775 A at up to 600 V AC, and three-phase SGT, SMB and SGB relays from 3\u00d724 A to 3\u00d7125 A at up to 660 V AC, with 4\u201330 V DC or 90\u2013280 V AC\/DC control and versions with push-in terminals. Accessories<\/a> include WF heatsinks from 3 down to 0.3 K\/W, thermal pads, DIN rail adaptors, mounting kits and the ESUC module that monitors current for up to five heaters. The DC Solid-State Motor Reverser<\/a> DRV handles up to 1.5 kV and 200 A. More components are under Components<\/a>.<\/p>\n How to choose:<\/strong> pick the number of phases and a current rating with margin, use zero-cross switching for resistive heaters, match the control voltage, then size the heatsink in K\/W for the load current and cabinet temperature.<\/p>\n A solid state relay, SSR, is an electronic switch without moving contacts that turns an AC or DC load on when a small control signal is applied. Since nothing wears mechanically, an SSR handles millions of cycles, switches silently and suits frequent switching such as heater control. The trade-off is heat: an SSR typically dissipates about 1 to 1.5 W per ampere and needs a heatsink.<\/p><\/details>\nFrequently asked questions<\/h3>\n
What is a solid state relay?<\/summary>