problems with the "index" part of it ! Ukazatel? Strelka? Zadannoe znachenie?
CONTEXT: In normal operation the pyrometer "index" is set to the desired temperature, circuit is on, blower(s) is on, and the control switch is set to AUTOMATIC. When the temperature is below "index" set point, High Power is on. When above "index" setpoint, the Low Power is on.