EC-NPB-2X-485 Option
HARDWARE INSTALLATION GUIDE
EC-NPB-2X-485 Option
05DI-HI2X485-13
Updated: September 2014
1
This document covers the mounting and wiring of the
EC-NPB-2X-485 option card in a Distech Controls
EC-BOS
AX
controller, including EC-BOS-2/3/6
AX
,
EC-BOS-7
AX
, or EC-BOS
AX
Security
series.
Refer to the appropriate EC-BOS
AX
hardware
installation document for further installation details.
Included in this Package
Included in this package find the following items:
•
EC-NPB-2X-485 option card, connector end plate,
and (if recent model) four 2-pin jumper blocks.
•
Two 3-position terminal plugs, for wiring to an
RS-485 network.
•
This
EC-NPB-2X-485 Option Hardware Installation
Guide
, 05DI-HI2X485-13.
Material and Tools Required
The following may be required for installation:
•
#2 Phillips screwdriver: used to install the card.
•
Small flat-blade screwdriver: used for making
wiring connections to the RS-485 networks.
Figure 1
EC-NPB-2X-485 option.
Preparation
Examine the component side of the option card to see
if bias resistor jumper pins are available. See
Figure 2
.
If so, you may wish to enable biasing for either (or
both) RS-485 ports
before mounting
the card—you
cannot reach these jumpers when the card is installed.
Figure 2
Jumpers to enable RS-485 bias resistors.
Note
An earlier EC-NPB-2X-485 option card does
not have Bias jumpers. It operates like the
newer option card in factory-shipped state
(jumper blocks not installed—no biasing).
Installing jumpers to enable biasing adds two onboard
3.3K ohm resistors into an RS-485 port’s circuit:
•
from RS-485 “+” to 5V.
Table 1 EC-NPB-2X-485 option description.
Description
Notes / COM Port Assignments
Dual port,
optically isolated
RS-485 adapter,
with two
3-position,
removable
screw-terminal
connector plugs.
See
Figure 3
on
page 2 for
location of
Option Slots 1
and 2 on an
EC-BOS-2/3/6
AX
.
Recent option cards have jumpers for
enabling onboard bias resistors. See
“Preparation,”
page 1, for more details.
Most EC-BOS
AX
models have two option
slots, where COM assignments are:
•
EC-BOS-2/3/6
AX
, EC-BOS
AX
Security
: If
single
RS-485 option in Slot 1: COM3,
COM4.
If
two
RS-485 options, ports are Slot 1:
COM3, COM4 and Slot 2: COM5, COM6.
•
EC-BOS-7
AX
: If
single
RS-485 option in
Slot 1: COM5, COM6.
If
two
RS-485 options, ports are Slot 1:
COM5, COM6 and Slot 2: COM7, COM8.
Also see
“COM Port Usage,”
page 3.
S
R
5
8
4
s
X
R
X
T
X
R
X
T
s
COM3 / COM5
COM7
COM4 / COM6
COM8
See Notes in
Table 1
.
Jumper pins to
enable RS-485
Bias resistors
(found on newer
cards only)
to bias
this port
to bias
this port
Screened
diagram
shows
how to enable a
port’s Bias
resistors
(two jumper
blocks on the
header pins).
