February 2022
Installation, Operation and Maintenance Manual
VCIOM-15345-EN Rev. 1
36
Communication Protocols
Section 5: Communication Protocols
5.3
FOUNDATION™ Fieldbus
EHO actuators supporting FOUNDATION™ Fieldbus H1 protocol are fully certified by
the Fieldbus Foundation and provide direct connection to the fieldbus with guaranteed
interoperability with other certified devices. Each network can comprise up to 32 devices,
with power for devices being provided via network cabling (assuming intrinsically safe
devices are not connected to the same network). Networks may extend up to 1,900 m
(6,000 ft) long, and repeaters may be used to extend the distance or to incorporate more
than 32 devices.
Figure 16
FOUNDATION Fieldbus Topology
Table 8.
FOUNDATION Fieldbus Pins
Pin Connections
Fieldbus Connections
43
FI
44
FIELDBUS -
42
Shield
Network System Control
Power Supply
32 V Nominal
Terminator
Trunk Cable
9 V Minimum
Sp
ur
Sp
ur
Terminator
Junction Box
