Solid state relay (SSR) is ideal equipment that using weak power to control strong power, which has extensive application in SCM measuring and controlling system.

In this paper, we introduced the Hazard Analysis and Critical Control Point(HACCP)system and the application of HACCP system which was used in solid-state fermetation vinegar.

Temperature computer control system of a resistance furnace is designed with industry person computer (IPC), temperature input module, PWM output card, solid state relay(SSR) and interrelated circuit.