** NOTE: The SNAP-AOA-23-iH is OBSOLETE and no longer available. ***
The SNAP-AOA-23-iH provides two channels of isolated analog output current with a range of 4–20 mA, and communicates with other Highway Addressable Remote Transducer (HART®) current loop devices. External loop power supplies are required for current loops.
Each channel features an integrated HART modem that allows the channel to communicate digitally with a HART FSK (frequency-shift keying) signal superimposed onto the analog 4–20 mA current loop. The channel is a master device when used together with SNAP PAC brains
to communicate with other HART current loop devices in either point-to-point or multidrop configurations.
The SNAP-AOA-23-iH is categorized by the HART protocol as a current output device, which means that each channel controls the loop current and is a high impedance device.
The module provides channel-to-channel isolation as well as transformer isolation and optical isolation. It is factory calibrated.
HART SNAP I/O modules are part of the SNAP PAC System. They mount on SNAP PAC racks alongside other SNAP I/O modules (analog, digital, and serial), so you have the combination of I/O you need at any location.
These modules require a SNAP PAC brain
or rack-mounted controller
for I/O processing and communications. They are not compatible with legacy brains and controllers.
HART SNAP I/O modules are designed for use with a SNAP PAC programmable automation controller and PAC Control
automation software. Several HART-specific commands are available in PAC Control (version 9.4 and higher) for these modules. See the module data sheet for additional information. Sample PAC Control subroutines
show you how to use commands to communicate with HART devices.
HART SNAP I/O modules can also be used without PAC Control. Use the SNAP PAC .NET HART developer toolkit
to integrate HART SNAP I/O modules into an existing .NET/Mono application.
NOTE: If you need a HART input module, see the SNAP-AIMA-iH