Embedded HART Multiplexer
Both the BMEAHI0812(H) input module and the BMEAHO0412(C) output module include an embedded HART multiplexer. The multiplexer facilitates the transmission of HART field instrument data by providing:
one-to-many HART communication between a single HART primary instrument and multiple HART field devices
HART instrument data to a PLC primary device, as part of the periodic scan
HART Primary and Secondary Instruments
A HART primary instrument can be either:
a configuration PC running EcoStruxure Automation Expert or asset management software
PC running SCADA as HART server
a secondary instrument, such as a hand-held device that can be temporarily connected directly to the current loop between an I/O module and the HART field instrument

1 Local rack containing a BMEP583040 CPU with remote I/O scanning service
2 Remote I/O rack containing a BMECRA312 10 adapter module
3 Remote I/O main ring
4 HART-enabled field instruments connected to I/O via 4-20 mA current loop wiring
5 Maintenance PC operating as HART primary instrument (running, for example, EcoStruxure Automation Expert configuration software or asset management software) or SCADA
6 Hand-held HART secondary device
The HART multiplexer supports one HART field instrument per I/O channel.

