| 摘要 |
PURPOSE:To realize precise humidity control by finding relative humidity by using a dry-bulb temperature signal and a wet-bulb temperature signal and then by performing humidification or dehumidification on the basis of the deviation from a reference humidity signal. CONSTITUTION:A dry-bulb temperature signal td and a wet-bulb temperature signal tw are inputted to a humidity arithmetic circuit RHOP through a preamplifier PA, a multiplexer MPX, and an AD conveter ADC. An arithmetic circuit PID performs control arithmetic so that the deviation between the dry-bulb temperature signal tdpv and a temperature set signal tdsp from a setter SET is zero, and then controls a hmidifying device and a cooling device by an output OUT#1. Further, the control arithmetic is so performed that the deviation between a relative humidity signal RHPV found by a humidity arithmetic circuit RHOP and a humidity set signal RHSP is zero, and then controls the humidifying device and a dehumidifying device by an output OUT#2. |
