Description of hart interface, 3 multi-drop connection (3-wire connection) – KROHNE IFC 300 Converter EN User Manual
Page 167
DESCRIPTION OF HART INTERFACE
9
167
IFC 300
www.krohne.com
08/2010 - 4000069803 - MA IFC 300 R04 en
9.3.3 Multi-Drop connection (3-wire connection)
Connection of 2-wire and 4-wire devices in the same network. In order that the current output of
the signal converter is working continuously active, an additional third wire must be connected
to the devices in the same network. These devices must be powered via a two-wire loop.
1 Primary Master
2 HART
®
modem
3 HART
®
signal
4 2-wire external devices (slaves) with 4…20 mA, addresses > 0, powered by current loop
5 Signal converter terminals A (C)
6 Signal converter terminals A- (C-)
7 Connection of active or passive 4-wire devices (slaves) with 4…20 mA, addresses > 0
8 Load ≥ 250 Ω (Ohm)
9 Secondary Master
10 Power supply