Network Controller 6 Mounting and Wiring Guide
Updated: January 16, 2012
Wiring Details
RS-485 Biasing
18
Step 6
Carefully pry up the NPM-6 board, noting that the two-row, 50-pin connector is on the option card
side. Keep the board level as you work it loose from this connector.
Step 7
Set the NPM board aside. Note the jumper block on the base board behind the RS-485 port.
Procedure 5
Installing shorting blocks to add RS-485 biasing.
Step 1
Locate the four jumper pins behind the RS-485 port.
Newer units have two 2-pin shorting blocks pre-installed on one pin each. See
.
Step 2
To add biasing, install a shorting block across both pins on each side of the jumper block, shorting the
pins as shown in
(right).
Figure 8
Install shorting blocks across both sides of the jumper block to add RS-485 biasing.
Procedure 6
Reassembling the controller
Step 1
Carefully replace the NPM-6 board back onto the 50-pin connector, with its corner mounting holes
aligned on the four lower standoffs. Press down on the connector to fully seat the NPM board. See
Step 2
Refasten the four metal hex standoffs, hand tightening with a 1/4" (7mm) nutdriver.
Step 3
Replace the shield back onto the unit. To do this, carefully ease it over the port side first; then spring
it down over the other side. Make sure its corner holes align with the metal standoffs below.
Step 4
Refasten the four Philips head screws that secure the shield to the standoffs.
Step 5
Replace the plastic cover onto the unit.
Shorting blocks
installed across
jumper pins
(biasing added)
Position of
pre-installed
shorting blocks
(no biasing)
Shorting blocks lifted away.
Part Number:
T-12086 2-pin shunt jumper
(Digikey 881545-1-ND, or
equivalent)