Section 2.8 Preparing And Wiring Cables - Spectrum Controls SLC 500 User Manual

Section 2.8
Preparing and
Wiring Cables
NOTE
NOTE
To prepare and connect cable leads and drain wires, follow these steps:
1. Determine the length of cable you need to connect a channel to its field
device. Remember to include additional cable to route the drain wire and
foil shield to their ground points.
2. At each end of the cable, strip some casing to expose the individual
wires.
3. Trim the exposed signal wires to 5-in. lengths. Strip about 3/16 in. (about
5 mm) of insulation away to expose the end of each wire.
4. At one end of the cable, twist the drain wire and foil shield together,
bend them away from the cable, and apply shrink wrap.
5. At the other end of the cable, cut the drain wire and foil shield back to
the cable and apply shrink
6. Connect the wires to the terminal block and field device as shown in the
following figures and table. The recommended maximum torque is
in-lb. (0.565 Nm) for all terminal screws.
7. To guard against electrostatic damage and improve chassis grounding,
connect one of the shield pins on the terminal block of your module to
the chassis itself.
8. Repeat steps 1 through 6 for each channel on your
IMPORTANT: If noise persists, try grounding the opposite end of the
cable, instead (Ground one end only.)
IMPORTANT: For CE compliance, Ferrite EMI Suppressors are needed
on each channel's terminal block connection. Apply the suppressor close
to the module terminal block, as shown below. A Steward Part 28B2024-
0A0 or equivalent is recommended. The Steward 28B2024-0A0 has an
impedance of 157 Ω at 25 MHz, 256 Ω at 100 MHz, and can
accommodate one turn of wire.
Chapter 2: Installation and Wiring
wrap.
User's Manual Pub. 0300181-07 Rev. A
2-7
4.5
module.