Nexstar AD 4305 Owner's manual

AD 4305
RS-485 MULTIPLEXER
Installation and
Operation
5452 Betsy Ross Drive
Santa Clara, CA 95054-1184
[phone]
FAX [phone]
P/N 66109923001 Rev. A

© 1996 Westinghouse Security Electronics. All rights reserved.
DigiReader, QuadraKey, DuraKey, NexKey and NexStar are trademarks of Westinghouse Security Electronics.
Printed in the United States of America.

LIMITED WARRANTY
Westinghouse Security Electronics (WSE) warrants to the original user the equipment
manufactured by WSE as described herein to be free from defects in material and workmanship
for a period of one year from the date of purchase by such user or fifteen (15) months from the
date of shipment from the factory, whichever is sooner (command key / magnetic stripe card
warranties differ, see below), provided:
I WSE has been notified within such period by return of any alleged defective
equipment, free and clear of any liens and encumbrances to WSE or its authorized
dealer at the address specified, transportation prepaid; and
II the equipment has not been abused, misused or improperly maintained and/or
repaired during such period; and
III such defect has not been caused by ordinary wear and tear; and
IV such defect is not a result of voltage surges/brownouts, lightning, water damage/
flooding, fire, explosion, earthquakes, tornadoes, acts of aggression/war, or similar
phenomena; and
V accessories used as integral to WSE systems have been approved by WSE (e.g.,
coaxial cables, batteries, etc.); and
VI the equipment has been installed, the installation supervised or installation tested by
an authorized WSE dealer.
WSE shall at its option, either repair or replace, free of charge, the equipment found, upon
WSEs inspection to be so defective.
WSE MAKES NO OTHER WARRANTY, AND ALL IMPLIED WARRANTIES INCLUDING ANY
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE
LIMITED TO THE DURATION OF THE EXPRESSED WARRANTY AS SET FORTH ABOVE.
WSES MAXIMUM LIABILITY HEREUNDER IS LIMITED TO THE PURCHASE PRICE OF
THE EQUIPMENT. IN NO EVENT SHALL WSE BE LIABLE FOR ANY CONSEQUENTIAL,
INDIRECT, INCIDENTAL OR SPECIAL DAMAGES OF ANY NATURE ARISING FROM THE
SALE OR USE OF THE EQUIPMENT.
Some states do not allow limitations on incidental or consequential damages or how long an
implied warranty lasts, so the above limitations may not apply. This warranty gives specific legal
rights; however, other rights which vary from state to state, may pertain.
Analog command keys are warranted for 5 years; digital command key / magnetic stripe card
warranties vary. See product literature.

iv
DR 4305 NexStar Installation and Operation
FEDERAL COMMUNICATIONS COMMISSION RADIO FREQUENCY
INTERFERENCE STATEMENT
The NexStar RS-485 Multiplexer sold by Westinghouse Security Electronics has been tested
and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC
Rules. These limits are designed to provide reasonable protection against harmful interference
in a residential installation. This equipment generates, uses and can radiate radio frequency
energy and if not installed and used in accordance with the instructions herein, may cause
harmful interference to radio communications. If this equipment does cause interference to
radio or television reception, consult the dealer or an experienced radio/television technician
for correction.
The user may find helpful the following booklet, prepared by the Federal Communications
Commission: How to Identify and Resolve Radio/TV Interference Problems." This booklet is
available from the US Government Printing Office, Washington DC 20402, stock number: 004-
000-00345-4.
UL-294 Notice
The NexStar RS-485 Multiplexer is UL-294 listed and may be used in a UL-294 listed
access control system. All system components must be UL-294 listed and installed
according to manufacturers' instructions to comply with UL-requirements.
294

P/N 66109923001 Rev A v
IMPORTANT WARNING
Do not connect the NexStar without having carefully read this guide. If this is the first time you have
installed this type of device, have another person check the connections before turning on the power.
The warranty is void if you damage any component because of an error in wiring a connection. Follow
these basic procedures and precautions to avoid damage to the components (local codes and practices
may also apply and must be complied with).

vi
DR 4305 NexStar Installation and Operation
Table of Contents
Scope ................................................................................................................................................... 1
Introduction ........................................................................................................................................... 1
Specifications ........................................................................................................................................ 2
Physical Description .............................................................................................................................. 2
Cover ............................................................................................................................................. 3
Base ............................................................................................................................................... 3
PCA ................................................................................................................................................ 4
LEDs ........................................................................................................................................ 4
Fuses ....................................................................................................................................... 5
Jumpers ................................................................................................................................... 5
Phoenix Connectors ........................................................................................................................ 5
Wire Insertion .......................................................................................................................... 6
S-Net Wiring ................................................................................................................................... 7
Termination .............................................................................................................................. 8
Installation Sequence ............................................................................................................................ 8
Troubleshooting .................................................................................................................................... 9
Communications Errors ............................................................................................................ 9
List of Figures
Figure Description Page
1 S-Net Layout using a NexStar ............................................................................................ 1
2 NexStar ............................................................................................................................. 2
3 Cover Label ....................................................................................................................... 3
4 NexStarBase and Mounting Holes .................................................................................... 3
5 NexStar Printed Circuit Assembly ...................................................................................... 4
6 Transmit LEDs ................................................................................................................. .. 5
7 Termination Jumper ........................................................................................................... 5
8 Connector Pin-Outs ........................................................................................................... 6
9 Wire Insertion .................................................................................................................... 6
10 Drop Wiring ....................................................................................................................... 7
11 S-Net Termination .............................................................................................................. 8
12 Branch Isolation ............................................................................................................... 10
13 Alternate Branch Isolation ................................................................................................ 10
List of Tables
Table Description Page
1 Specifications .................................................................................................................... 2
2 Component Locations ........................................................................................................ 4
3 Approved Fuse Vendors .................................................................................................... 5
4 Recommended S-Net Cable .............................................................................................. 7
5 Troubleshooting ................................................................................................................. 9

P/N 66109923001 Rev. A 1
SCOPE
This manual provides information necessary to install, use and troubleshoot a NexStar RS-485
Multiplexer. It is assumed that the person reading this manual is familiar with access control
systems and standard installation practices. The information provided in this manual is not
intended to conflict with the building, electrical, fire or safety codes required for any given
installation.
INTRODUCTION
The NexStar is a symmetrical 5-port repeater with built-in arbitration logic. Any one port will
relay the data it receives to the other four ports. Bus arbitration is done on a first-come, first-
served basis. During periods of no activity, the NexStar automatically places all 5 ports into the
receive mode to wait for the next message.
The NexStar provides a link between a WSE access control unit, such as the NexSentry or SE
818SC, and multiple S-Net runs. A single S-Net run may be a maximum of 4000 feet (1200
meters). Using all of the NexStar 's five symmetrical ports, the end-to-end S-Net length can
span up to 8000 feet (2400 meters) and contain up to 20,000 feet (6000 meters) of installed
wiring.
4000 FEET
(1200 METERS)
NEXSTAR
DR 4205K
DR 4205K
DR 4205
DR 4208
DR 4204
DR 4204
VIP2
MSRK
ACCESS
CONTROL
UNIT
Figure 1: S-Net Layout using a NexStar

2
DR 4305 NexStar Installation and Operation
In the simplest configuration, the NexStar allows home-run wiring which eliminates excessively
long wire runs and the need to make multiple connections to a single terminal block
SPECIFICATIONS
Specifications for the NexStar are shown in the table below.
Table 1: Specifications
Inp ut Voltag e +15 to +28 VDC
Opera ting Current 50mA
Pass-Thru Current 2A
Operating Humidity 0 to 90%, non-condensin
g
Operating Temperature -4° F to 50° F -20° C to +50° C
Size 8 in X 4.5 in X 1.5 in 20 cm X 11 cm X 3.5 cm
Weight 13 oz 400
g
PHYSICAL DESCRIPTION
The NexStar consists of a single printed circuit assembly (PCA) in a two-part housing. Male
Phoenix connectors on the PCA are accessed through the side of the housing for port
connections.
4 PLACES
COVER
PCA
BASE
Figure 2: NexStar

P/N 66109923001 Rev. A 3
COVER
The cover of the NexStar snaps onto the base. The LEDs mounted on the PCA are visible
through holes on the cover. A label identifies the LEDs and pin-out wiring for each port.
COM ACTIVE
TX-1 TX-2 TX-3 TX-4 TX-5
SHIELD
COMMON
DATA
DATA+
+28 VDC
SHIELD
COMMON
DATA
DATA+
+28 VDC
SHIELD
COMMON
DATA
DATA+
+28 VDC
SHIELD
COMMON
DATA
DATA+
+28 VDC
SHIELD
COMMON
DATA
DATA+
+28 VDC
Figure 3: Cover Label
BASE
The base of the housing has four through holes for mounting the NexStar to a wall or other
surface. Four standoffs are affixed to support the PCA.
3.2 in
8.1 cm)
7.29 in
(18.5 cm)
MOUNTING HOLE
4 PLACES
STANDOFF
4 PLACES
Figure 4: NexStar Base and Mounting Holes

4
DR 4305 NexStar Installation and Operation
PCA
All components and circuitry are contained on the single PCA. Figure 5 shows the board
locations of connectors, fuses, LEDs and jumpers. These components are listed in Table 2 and
further described below.
Figure 5: NexStar Printed Circuit Assembly
Table 2: Component Locations
PCA Location
Label Fu nction LED Connector Jumper Fuse
TX-1 Port 1 Transmit CR18 J5 JP5 F5
TX-2 Port 2 Transmit CR17 J4 JP4 F4
TX-3 Port 3 Transmit CR16 J3 JP3 F3
TX-4 Port 4 Transmit CR15 J2 JP2 F2
TX-5 Port 5 Transmit CR14 J1 JP1 F1
COM ACTIVE Active CR19
LEDS
The COM ACTIVE LED will be illuminated when any data is being passed through the NexStar.
The five port LEDs will illuminate when the associated port is transmitting. On the left side of
Figure 6, the NexStar is receiving data from an ACU on port one. This data is then transmitted

P/N 66109923001 Rev. A 5
to all the remaining ports. All LEDs except TX-1 are illuminated. On the right side of the figure,
the NexStar is receiving data from an S-Net device on port 3. Again, data is transmitted to all
other ports; all LED's except TX-3 are illuminated.
ACU S-NET S-NET S-NET S-NET
TX-1 TX-2 TX-3 TX-4 TX-5
COMM ACTIVE
ACU S-NET S-NET S-NET S-NET
TX-1 TX-2 TX-3 TX-4 TX-5
COMM ACTIVE
Figure 6: Transmit LEDs
Note: High speed network communications may cause all LEDs to appear illuminated.
FUSES
Each of the five ports on the NexStar is individually fused. Fuses for the ports are located at
positions F1 through F5 on the PCA. These fuses are 2-amp, normal-blow. Approved suppliers
for replacement fuses and the vendor's part numbers are shown in Table 3.
Table 3: Approved Fuse Vendors
Ven dor Part Number
L i tt l e fu s e 273002
Bel MB2
JUMPERS
Five jumpers on the PCA can be used to provide termination required (see page 8) for S-Net
lines. Installing a jumper enables a 120-ohm, ¼ watt resistor.
NO TERMINATION 120 OHMS TERMINATION
Figure 7: Termination Jumper
PHOENIX CONNECTORS

6
DR 4305 NexStar Installation and Operation
D
ata twisted pair
Power and Ground
twisted pair
SHIELD
GROUND
DATA
DATA+
+28 VDC
Figure 8: Connector Pin-Outs
The shield wire is connected to the ACU ground to provide single-point grounding. See the
appropriate ACU manual for additional information.
WIRE INSERTION
For wire insertion to Phoenix connectors, the following procedure is recommended:
1. Strip the wire end.
2. Twist the exposed strands tightly and tin the ends.
3. Crimp an appropriate size ferrule on the end of the wire. Be sure that the ferrule is crimped
on bare conductor metal, not the insulation.
CRIMP
SLEEVE
WIRE
PHOENIX
CONNECTOR
Figure 9: Wire Insertion
4. Insert ferrule in the appropriate Phoenix connector terminal. Tighten the connector binding
screw and torque to 5 inch-pounds (0.56Nm).

P/N 66109923001 Rev. A 7
S-NET WIRING
S-Net is a serial network for communication between the ACU and node devices. Typically, the
cable used is two twisted-pairs with an overall shield; one pair is for data, the other pair is for
DC power. While the maximum length of an S-Net branch is 4,000 feet (1200 meters), it is
recommended that separate twisted-pair cables for data and power when lengths exceed 500
feet (150 meters). Table 4 lists recommended cable.
Table 4: Recommended S-Net Cable
Ty p e Description Gauge
S-Net Length < 500 Feet
Data and Power
Belden 9552
Belden 1069 2-Pair 18 AWG
16 AWG
S-Net Length > 500 Feet
Data Only Belden 9841 1-Pair 24 AWG
S-Net Length > 500 Feet
Powe r Only
Belden 9341
Belden 9342
Belden 9343
2-Conduct or
18 AWG
16 AWG
14 AWG
S-Net cable should be installed as a single cable; splices should be soldered or secured with
crimp lugs. Drop-lines to a S-Net devices should not exceed 6 feet (1.85 meters) in length.
S-NET
DEVICE
DROP
MAXIMUM LENGTH
6 FT (1.85 M)
DO NOT TERMINATE
S-NET RUN
MAXIMUM LENGTH
4000 FT (1200 M)
TERMINATE AT EACH END
CRIMP LUGS
OR SOLDER
Figure 10: Drop Wiring

8
DR 4305 NexStar Installation and Operation
TERMINATION
Each S-Net run must be terminated at each end with a 120-ohm, ¼ watt resistor connected
between the data lines. Figure 11 is a sample block diagram indicating where termination
resistors must be installed. In this diagram, an S-Net device may be an ACU, DigiReader,
keypad, etc. See Figure 7 for installing the termination jumpers for NexStar ports.
Figure 11: S-Net Termination
INSTALLATION SEQUENCE
The basic steps to install the NexStar are:
1. Install S-Net wiring. See page 7 for wiring information
2. With cover on to protect the PCA, mount te NexStar base. See Figure 4.
3. Terminate S-Net branches at each end. See the above for information on termination
requirements for each S-Net branch. Remove the NexStar cover to install jumpers as
required.
4. Replace the NexStar cover if removed in step 3.
5. Make S-Net connections.

P/N 66109923001 Rev. A 9
TROUBLESHOOTING
Table 5 lists error symptoms and suggests troubleshooting actions.
Table 5: Troubleshooting
Po wer Fault s
No LEDs illuminated
Check fuses
Check wirin
g
Ver if
y
DC volta
g
e to unit
If
p
ower is
p
resent, ACU ma
y
be off-line
No communciations on one
p
ort
Check
p
ort fuse
Check
p
ort wirin
g
No
p
ower at one or more
p
orts
Check fuses for affected
p
orts
Ch eck wirin
g
for affected
p
orts
Comm unications Errors
All li
g
hts stead
y
exce
p
t on one
p
ort Data A and data B wirin
g
ma
y
be reve rsed. Check wirin
g
on
p
ort with unlit LED.
Excessive data errors
Check wirin
g
shield connections for
g
round loo
p
s
Check termination resistors and
j
um
p
ers
COMMUNICATIONS ERRORS
1. Keep port with the ACU connected to the NexStar (see Figure 12).
2. If the ACU branch does not include other S-Net devices, connect a second branch (see
Figure 13).
3. Verify correct operation of ACU and S-Net devices.
4. If problems are detected, perform troubleshooting procedures for communications errors
as listed in Table 5.
5. When no problems are detected, connect other branches, one at a time, and repeat steps
3 and 4.

10
DR 4305 NexStar Installation and Operation
Figure 12: Branch Isolation
Figure 13: Alternate Branch Isolation