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1.5
isNet H@rt
With the isNet H@rt Module the main module isNet Lite can be
extended to work as an HART-Ethernet-Gateway. The HART-Eth-
ernet-Gateway is an up-to-date option to replace the widely used
RS485 HART multiplexer solutions, as it enables the direct connec-
tion to the existing data network of a plant. The isNet H@rt modules
are equipped with either four or eight channels. Up to five HART
modules can be connected to the main module, so a maximum of 40
HART channels can be operated in parallel. Each channel provides
galvanic decoupling from the HART line. Access to the HART network
is achieved by screw-type terminals.
Wiring from the isNet H@rt module to an existing control loop is as
easy as connecting a mobile HART modem to the 2 HART wires. The
isNet H@rt module can be thought of as 4 (or 8) independent HART
modems in a single enclosure. Each HART channel must be connect-
ed in parallel to the 2 wires of the control loop regardless of its po-
larity. Depending on the input impedance of the Analog Input line
of the PLC a 240 Ohm communication resistor might be necessary.
This applies especially to Analog Inputs without HART capability,
which usually contain a small sense resistor with an input impedance
of about 10 Ohm. If the PLC is HART enabled, the 240 Ohm resistor
was already built in.
With the isNet H@rt CommDTM, the modules can be integrated in
your FDT Frame Application. Based on the HART over IP protocol,
access from the popular HCF OPC server is possible as well.
