The Aquamonix Emflux 500 series flowmeter transmitters have three expansion card slots.
The HART & Ethernet expansion card adds communications functionality.
The HART (Highway Addressable Remote Transducer) protocol is a hybrid analog-and-digital industrial automation protocol that allows smart field instruments to communicate via existing 4-20 mA wiring. It uses FSK (Frequency Shift Keying) to superimpose digital signals on the analog loop, enabling remote configuration, diagnostics, and multiple variable monitoring without additional cabling.
The provision of MODBUS over Ethernet / IP allows the flowmeter to be connected directly to local area networks and pump station/industrial Ethernet based switch gear.