Libratherm offers Microcontroller based multiple Ramp Soak programmable PID temperature controller
Model PRC-489 which is designed to improve reliability, accuracy and control for all temperature control
applications. It features Ramp and Soak functions (the capability to control the temperature and its rate of
change over a predetermined time span). Single pattern of total 16 (rampsoak) steps can be programmed
and stored in the memory. It can also be used as single set point control when the rampsoak profile control is
not desired. Inputs can be Thermocouple, IR Thermocouple, RTD Temperature Sensors, Voltage, Current
Signals etc.
PRC-489 offers both switching outputs in the form of SSR driverTriac (AC SSR) for external SSR or external
load contactor and analog output in the form of (4-20) mA or (0-5) volt control signal, which can be used to
control heater power through Thyristor power regulator (for electrical heating system) or to control the
position of a modulating motor valve (for oil or gas fired heating systems). The analog outputs can be directly
connected to Libratherm make single phase three phase SCR phase angle or zero cross over fired power
controller which is ideally suitable for both resistive and inductive heating loads.

Libratherm offers Microcontroller based multiple Ramp Soak programmable PID temperature controller
Model PRC-489 which is designed to improve reliability, accuracy and control for all temperature control
applications. It features Ramp and Soak functions (the capability to control the temperature and its rate of
change over a predetermined time span). Single pattern of total 16 (rampsoak) steps can be programmed
and stored in the memory. It can also be used as single set point control when the rampsoak profile control is
not desired. Inputs can be Thermocouple, IR Thermocouple, RTD Temperature Sensors, Voltage, Current
Signals etc.
PRC-489 offers both switching outputs in the form of SSR driverTriac (AC SSR) for external SSR or external
load contactor and analog output in the form of (4-20) mA or (0-5) volt control signal, which can be used to
control heater power through Thyristor power regulator (for electrical heating system) or to control the
position of a modulating motor valve (for oil or gas fired heating systems). The analog outputs can be directly
connected to Libratherm make single phase three phase SCR phase angle or zero cross over fired power
controller which is ideally suitable for both resistive and inductive heating loads.