Emerson Rosemount 3490 Series, Справочное руководство

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(shield) connected to terminal 3 (marked with earth/ground symbol) on the control unit.
The cable screen (shield) should be left unconnected at the transmitter end unless there is
a terminal specifically provided for this purpose.
Cable runs should be separate from any high voltage or mains cables to avoid crosstalk or
interference.
Figure 3-5 shows the layout of the control unit terminals. All terminal blocks are suitable
for wires 14 to 26 AWG (0.5 to 1.5 mm
2
), except the mains terminals which are suitable for
wires 10 AWG (2.5 mm
2
). Insulation should be stripped back
¼
-in. (7 mm).
Figure 3-5: Connection Terminals Layout (for Mains-Powered Wall-Mount Unit)
The dc powered unit has a slightly different layout – terminals 31 and 32 replace terminals
28 and 29.
Transmitter connections are made on the left side of the terminals enclosure. Connecting
the intrinsically safe earth/ground (terminal 30) to a high integrity earth/ground point is
recommended if the transmitter connected to terminals 1 and 2 is in a hazardous area
Note
In intrinsically safe systems, apparatus connected to the Rosemount 3490 Series Control
Unit must not be supplied from a voltage greater than 250 V r.m.s. or 250 Vdc.
Installation Reference Manual
January 2021 00809-0100-4841
24 Emerson.com/Rosemount