Sept. 29, 2014 – Industrial automation manufacturer Opto 22 has released the SNAP-AIMA-iH and SNAP-AOA-23-iH two-channel analog input and output modules, each with HART communications. Both SNAP I/O modules use the HART communications protocol to extract status, diagnostics and other information from smart devices such as field-mounted process transmitters and analyzers. This information can be used by the automation system and/or the asset management system to increase uptime, improve productivity and enhance safety, the company says. The SNAP-AIMA-iH analog input module has two isolated 4-20 mA input channels, and the SNAP-AOA-23-iH output module has two isolated 4-20 mA output channels. Each channel features an integrated HART modem that allows the channel to communicate digitally with the HART FSK (frequency-shift keying) signal imposed on the 4-20 mA current loop, enabling communication with the target smart device. Each channel is a HART master device when used with Opto 22 programmable automation controllers (PACs), and can communicate with other HART current loop devices in either point-to-point or multidrop configurations. The SNAP-AIMA-iH analog input module is categorized by the HART protocol as a current input connection type, which means that the module is a low-impedance device. The SNAP-AOA-23-iH analog output module is categorized by the HART protocol as a current output device, which means that each channel can provide the required loop current and is a high-impedance device.
