Rosemount 752, Reference Manual

Page: 14 / 60

Reference Manual
00809-0100-4377, Rev BA
September 2010
Rosemount 752
2-4
Shield Wire Ground
To protect the fieldbus segment from noise, grounding techniques for
shield wire usually require a single grounding point for shield wire to avoid
creating a ground loop. The ground point is typically at the power supply.
Figure 2-3. Fieldbus indicator
field wiring
Surges/Transients
The indicator will withstand electrical transients of the energy level usually
encountered in static discharges or induced switching transients. However,
high-energy transients, such as those induced in wiring from nearby
lightning strikes, can damage the indicator.
Optional Transient Protection Terminal Block
The transient protection terminal block can be ordered as an installed
option (Option Code T1 in the indicator model number) or as a spare part.
The spare part number is 03151-4134-0002. The lightning bolt symbol
shown identifies it as a transient protection terminal block.
NOTE
The fieldbus physical layer specification requires indicator communication
during extreme operating conditions of 250 V
rms
common mode signal. The
transient terminal block was designed to limit common mode voltages to 90 V
and cannot be used in these extreme operating conditions.
Power
Supply
F
OUNDATION
fieldbus
Configuration
Tool
Terminators
Integrated Power
Conditioner
and Filter
(Trunk)
(Sp
u
r)
(Spu
r)
(The power supply, filter, first
terminator, and configuration tool are
typically located in the control room.)
Signal
Wiring
Fieldbus
Segment
6234 ft (1900 m) max
(depending upon cable
characteristics)
*Intrinsically safe installations may allow fewer devices per I.S. barrier due to current limitations.
fieldbus
devices on
segment