The Ketotek KT8230 is a stand‑alone digital temperature controller for high‑current loads. Operating on 120 VAC, it switches a 30 A relay to control heating or cooling equipment. It uses an external NTC probe and covers a wide setpoint range of −22 to 572 °F (−30 to 300 °C) with 1 °F accuracy. Functions include selectable heat/cool mode, adjustable differential, a 0–7 minute delay start for compressor protection, and a user calibration offset. Safety features provide alarms for sensor faults and out‑of‑range temperatures, and settings are retained after power loss. Typical uses include incubators, brooders, refrigerators, fermenters, greenhouses. Package content commonly includes the controller and a roughly 2 m probe lead for flexible sensor placement.