Solid State Relays for Electric and Glass Firing kilns. A solid-state relay (SSR) is an electronic switching device that switches on or off when an external voltage (AC or DC) is applied across its control terminals. It serves the same function as an electromechanical relay, but has no moving parts and therefore results in a longer operational lifetime.
When making your selection, if the kiln model is built for 3-phase wiring, you must click on the amps and the 3-phase wiring option; or if the kiln is built for 3-zone control, you must click on the amps and 3-zone control option.