When to specify solid-state relays in control cabinets
High-cycle heaters and silent panels benefit from SSRs. Electromechanical contactors still win on inrush and galvanic isolation.
High-cycle heaters, PID loops and silent panels benefit from solid-state relays. Electromechanical contactors still win on motor inrush, isolation and a visible contact state that a night-shift electrician can trust.
Many OEM cabinets mix the two: an SSR on the temperature zone, a TeSys / AF / DIL contactor on the motor. That is the right split. Do not put an SSR on a reversing motor without the manufacturer’s reversing kit, and do not put a tiny interface relay on a heater that needs a heatsink rating.
We list photographed relays and contactors. Quote the coil voltage, contact arrangement and whether the load is AC-1, AC-3 or a heater. The type key on the side of the body is worth more than a photo of the front bezel.