Most manufacturing operations are full of HART smart instruments. Often there are additional process variables from these HART devices that are being measured but simply can’t be monitored because the field device only has one 4-20mA output. If the DCS or BPCS is HART capable then these hosts could poll these smart HART instruments for this additional diagnostic and process data. Unfortunately upgrading older input cards or legacy control systems to be HART smart compatible can be quite expensive.
When this condition exists, utilize the Class I Div 2/Zone 2 approved HIM HART Interface Module. The HIM has the ability to poll any HART smart device and turn its digital HART process measurement data into 4-20mA signals (up to three) for retransmission to any host. In addition the HIM has optional alarm relays (up to two) that can be used to alarm on anything from diagnostic bits, transmitter status to process variable limits. The HIM is even multi-drop capable with an optional MODBUS RTU output that allows a remote MODBUS RTU host to poll it for the field transmitter’s HART variables; thus turning the HIM into an industrial HART-to-MODBUS gateway.
- HART to Analog Conversion: up to three AOs and two relay alarms
- Local display
- Class I Div 2/Zone 2 approval