System 800xA offers flexible and modular I/O solutions through fieldbus technologies and hardwired I/O systems like S800 and S900. The system is now enhanced with Select I/O that allows to condition each signal coming from the field individually. Select I/O is Ethernet connected and consist of single channel granular Signal Conditioning Modules (SCM).

AOS880 a Analog Output Signal Conditioning Module High Integrity for 2-wire devices. 16 bit. HART communication. Certified for SIL3.

Features and benefits

• Analog output for 2-wire field devices
• Signal range: 4...20 mA
• Can be used in hazardous areas
• Certified for Functional safety
• Transmitter power current limited to 30 mA
• 16 bit A/D converter resolution
• Channel to channel galvanic isolation
• Configurable output rise/fall times (down to 1ms; with HART down to 20 ms)
• Safe state shutdown (0 V) in case of internal failures or lost communication.)
• Protected against wrong wiring
• Configurable software filter

• Diagnostics:
– Loop supervision (open circuit and short circuit)
– Hardware error supervision
– Communication supervision
– Internal power supervision

• Support of HART field devices (up to HART application layer revision 7)
– HART Pass-Through
– Cyclic read of up to two HART Device Variables
– HART Device Validation

• Single loop granularity - each SCM handles a single channel.
• Supports hot swap
• Mechanical locking slider which turns off field device power and/or output before removal.
• Field disconnect function which can galvanically separate the field loop wiring from the SCM during commissioning and maintenance.
• All SCMs have electronic current limitation
• Mechanical keying to prevent insertion of wrong module type after commissioning.
• 24V DC powered through Modulebus
• Configurable through parameters
• LED indicators on the SCM indicate the operational state of the module.
• Certified for SIL3