The DeltaV I/O subsystem supports single I/O channels called CHARMs as well I/O cards with multiple channels. CHARMs and I/O cards convert field signals to the appropriate format for control and communications. Analog input and output CHARMs, discrete input and output CHARMs and RTD and Thermocouple input CHARMs are supported. CHARM terminal blocks provide the keying and field wiring terminals for the CHARMs.
Multiple types of I/O cards, including analog and discrete input and output cards, HART input and output cards, serial cards, the H1 fieldbus card, AS-Interface card, Profibus DP card, RTD, ohms, Thermocouple, mV, Multifunction, and the SOE (Sequence of Events) card are supported. Terminal blocks provide the keying and field wiring for the I/O cards.