The relative humidity controller shall be microprocessor based. For general application, it shall use a high polymer type sensor with a range of 30-80% and accuracy 5% of relative humidity. For critical applications, the sensor used shall be capacitive type with a range of 0-100% and accuracy of 3% of relative humidity.

For ON/OFF application the controller shall have a changeover contact of 230V, 3 Amp rating. For modulating application, the output shall be 3 point or 0-10 VDC.