Wiring For 4-Wire Remote Installations - Emerson Micro Motion 2700 Installation Manual

Wiring the Transmitter to the Sensor continued
User-supplied 4-wire cable must meet the following requirements:
• Twisted pair construction
• The gauge requirements as described in Table 2-2
• The applicable hazardous area requirements, if the core processor is installed in a hazardous
area (see the ATEX, IECEx, CSA, or UL documents shipped with the transmitter or available
on the Micro Motion web site)
3.2.2 9-wire cable
Micro Motion offers three types of 9-wire cable: jacketed, shielded, and armored. Refer to Micro
Motion's 9-Wire Flowmeter Cable Preparation and Installation Guide for detailed descriptions of
these cable types and for assistance in selecting the appropriate cable for your installation.
3.3

Wiring for 4-wire remote installations

To connect the cable, follow the steps below.
1. Prepare the cable as described in the sensor documentation.
2. Connect the cable to the core processor as described in the sensor documentation.
3. To connect the cable to the transmitter:
a. Identify the wires in the 4-wire cable. The 4-wire cable supplied by Micro Motion consists
of one pair of 18 AWG (0,75 mm
VDC connection, and one pair of 22 AWG (0,35 mm
should be used for the RS-485 connection.
b. Connect the four wires from the core processor to terminals 1–4 on the mating connector
of the transmitter. See Figure 3-1. Never ground the shield, braid, or drain wire(s) at the
transmitter.
Figure 3-1 4-wire cable between core processor and transmitter
Core processor terminals
VDC+
(Red)
VDC–
(Black)
20
Maximum cable length: see Table 2-2
RS-485B
(Green)
factory-supplied cable
RS-485A
(White)
2
) wires (red and black), which should be used for the
4-wire cable
User-supplied or
Transmitter Installation: Model 1700 and 2700 Transmitters
2
) wires (green and white), which
Mating connector
(transmitter)
VDC+
VDC–
RS-485A
RS-485B