Black Box IC155A, IC158A User Manual

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FEBRUARY 1998

IC155A(E)
IC158A(E)

RS-485 Repeater and

RS-485 Repeater (Opto-Isolated)

RS-485 REPEATER

PWR CDB CDA

3

FEDERAL COMMUNICATIONS COMMISSION

AND

CANADIAN DEPARTMENT OF COMMUNICATIONS

RADIO FREQUENCY INTERFERENCE STATEMENTS

This equipment generates, uses, and can radiate radio frequency energy
and if not installed and used properly, that is, in strict accordance with the
manufacturer’s instructions, may cause interference to radio
communication. It has been tested and found to comply with the limits for
a Class A computing device in accordance with the specifications in Subpart
J of Part 15 of FCC rules, which are designed to provide reasonable
protection against such interference when the equipment is operated in a
commercial environment. Operation of this equipment in a residential area
is likely to cause interference, in which case the user at his own expense will
be required to take whatever measures may be necessary to correct the
interference.

Changes or modifications not expressly approved by the party responsible
for compliance could void the user’s authority to operate the equipment.

This digital apparatus does not exceed the Class A limits for radio noise emission from
digital apparatus set out in the Radio Interference Regulation of the Canadian
Department of Communications.

Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les
limites applicables aux appareils numériques de classe A prescrites dans le Règlement
sur le brouillage radioélectrique publié par le ministère des Communications du
Canada.

TRADEMARKS

All applied-for and registered trademarks are the property of their
respective owners.

4

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)

NORMAS OFICIALES MEXICANAS (NOM)

ELECTRICAL SAFETY STATEMENT

INSTRUCCIONES DE SEGURIDAD

1. Todas las instrucciones de seguridad y operación deberán ser leídas
antes de que el aparato eléctrico sea operado.

2. Las instrucciones de seguridad y operación deberán ser guardadas
para referencia futura.

3. Todas las advertencias en el aparato eléctrico y en sus instrucciones de
operación deben ser respetadas.

4. Todas las instrucciones de operación y uso deben ser seguidas.

5. El aparato eléctrico no deberá ser usado cerca del agua—por ejemplo,
cerca de la tina de baño, lavabo, sótano mojado o cerca de una alberca,
etc..

6. El aparato eléctrico debe ser usado únicamente con carritos o
pedestales que sean recomendados por el fabricante.

7. El aparato eléctrico debe ser montado a la pared o al techo sólo como
sea recomendado por el fabricante.

8. Servicio—El usuario no debe intentar dar servicio al equipo eléctrico
más allá a lo descrito en las instrucciones de operación. Todo otro
servicio deberá ser referido a personal de servicio calificado.

9. El aparato eléctrico debe ser situado de tal manera que su posición no
interfiera su uso. La colocación del aparato eléctrico sobre una cama,
sofá, alfombra o superficie similar puede bloquea la ventilación, no se
debe colocar en libreros o gabinetes que impidan el flujo de aire por los
orificios de ventilación.

10. El equipo eléctrico deber ser situado fuera del alcance de fuentes de
calor como radiadores, registros de calor, estufas u otros aparatos
(incluyendo amplificadores) que producen calor

.

5

11. El aparato eléctrico deberá ser connectado a una fuente de poder sólo
del tipo descrito en el instructivo de operación, o como se indique en el
aparato.

12. Precaución debe ser tomada de tal manera que la tierra fisica y la
polarización del equipo no sea eliminada.

13. Los cables de la fuente de poder deben ser guiados de tal manera que
no sean pisados ni pellizcados por objetos colocados sobre o contra
ellos, poniendo particular atención a los contactos y receptáculos donde
salen del aparato.

14. El equipo eléctrico debe ser limpiado únicamente de acuerdo a las
recomendaciones del fabricante.

15. En caso de existir, una antena externa deberá ser localizada lejos de las
lineas de energia.

16. El cable de corriente deberá ser desconectado del cuando el equipo no
sea usado por un largo periodo de tiempo.

17. Cuidado debe ser tomado de tal manera que objectos liquidos no sean
derramados sobre la cubierta u orificios de ventilación.

18. Servicio por personal calificado deberá ser provisto cuando:

A: El cable de poder o el contacto ha sido dañado; u
B: Objectos han caído o líquido ha sido derramado dentro del

aparato; o
C: El aparato ha sido expuesto a la lluvia; o
D: El aparato parece no operar normalmente o muestra un cambio en

su desempeño; o
E: El aparato ha sido tirado o su cubierta ha sido dañada.

6

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)

Contents

Chapter Page

1.0 Specifications............................................................................ 7

2.0 Introduction............................................................................. 8

2.1 Optical Isolation ............................................................... 8

2.2 Indicators and Connectors............................................... 8

3.0 Installation ............................................................................... 9

3.1 Setting Jumpers and Switches.......................................... 9

3.2 Connecting the Repeater to Your Network .................... 11

Appendix......................................................................................... 15

A.1 The RS-485 Repeater Delay Circuitry............................. 15

A.2 Connector Pinning........................................................... 16

A.3 Network Performance...................................................... 17

Quick Setup Guide ......................................................................... 18

7

CHAPTER 1: Specifications

Speed —

Transparent to baud rate

up to 128 Kbps

Maximum distance —

4000 ft.

(1.2 km)

Operation —

Full- or half-duplex

Leads supported —

Both ports:

TDA-, TDB+, RDA-, RDB+

Indicators —

Both ports: CD

(Carrier Detect); Power

Flow control —

Transparent to

flow control. (

NOTE:

Repeater

does not

support hardware flow

control.)

Interface —

RS-485

Connectors —

(2) 4-screw terminal
block; (2) RJ-45, (1) edge card
connector

Power —

Primary: 115 VAC ±
10%/60 Hz model or 230 VAC ±
10%/50 Hz model; Secondary:
17 VAC center tap, 750 mA

Size —

1.8”H x 5.5”W x 8.5”D

(4.6 x 14 x 21.6 cm)

Weight —

2 lb. (0.9 kg)

1.0 Specifications

8

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)

The RS-485 Repeaters extend your
RS-485 communications beyond the
4000-foot limit. Even located 5000
feet from your master device, they’ll
take your RS-485 communications
signals and shoot them out another
4000 feet.

And they let you add more devices
to your network—up to 32 more
unit loads per Repeater. The RS-
485 Repeaters are perfect for
connecting multiple RS-485
segments located in different
rooms, on different floors, or in
different buildings.

They support either 2- or 4-wire
applications, in full- or half-duplex
operation. Plus they come with a
4-screw terminal-block, RJ-45
connectors, and an edge card
connector, so they fit right in with
any RS-485 wiring scheme.

2.1 Optical Isolation (IC158A only)

The opto-isolating model protects
one segment of your extended
network from problems that arise
on the other. Inside the Repeater,
optical-isolation circuitry converts
electrical signals to light and back
again, to keep signal noise and
ground loops from crossing
between segments of your RS-485
installation. That means the
electrical noise from your factory
floor won’t affect your office

communications, and the difference
in ground potential between
buildings won’t damage your
sensitive equipment.

2.2 Indicators and Connectors

Three LEDs are visible through the
Repeater's translucent front panel:
one Power LED and two Carrier
Detect (CD) LEDs. The power LED
lets you know the Repeater is on,
while the CD LEDs indicate when a
transmitter is enabled on the RS-
485 line.

Five connectors are accessible
through the Repeater back panel:
the Power connector, two RJ-45
connectors, and two 4-screw
terminal blocks. The Port A
terminal block and the RJ-45
connector are wired in parallel to
each other. Thus the A and B ports
of the repeater can be accessed
through either a terminal-block
connector or an RJ-45 connector.
(See Figs. 3-1 and 3-2 for the
position of these components on
the Repeater circuit board.)

Chapter 3.0

covers installation of
the RS-485 Repeaters in your
setup.

NOTE:

The RS-485 Repeater has
no collision detection. It is up to
the addressable devices on the
RS-485 network to ensure that only
one transmitter is enabled at any
one time.

2.0 Introduction

9

CHAPTER 3: Installation

Installing the RS-485 Repeater in
your setup is simple: Just set
internal jumpers and switches to
your application, connect your
devices to the Repeater, power up
the Repeater, and power up the
rest of your RS-485 network.

NOTE:

Refer to Figs. 3-1 and 3-2
for the location of components on
your repeater model.

3.1 Setting Jumpers and Switches

Here's how to set the Repeater's
jumpers and DIP switches for your
application:

1. Use jumpers W3 and W4 to
configure the RS-485 Repeater
for either 2- or 4-wire cabling.

When both are in the BC
position, the Repeater is set for
4-wire cabling and either half-
or full-duplex operation.
When both are in the AB
position, the Repeater is set for
2-wire, half-duplex operation.

2. Jumpers W1 and W2 have no
effect when the Repeater is set
for 4-wire, full-duplex mode,
but in half-duplex operation
they determine the
turnaround delay for the
Repeater's receiver.

W1 and W2 set the delay
between the time that the

3.0 Installation

Fig. 3-1. The RS-485 Repeater Circuit Board.

RJ-45

Connectors

Power

Connector

D
C
B
A

D
C
B
A

A
B
C

A
B
C

Edge Card
Connector

PORT

J1

PORT

J2

P6

TB1

RDB
RDA
TDB
TDA

A

B

Q1

TB2

RDB
RDA
TDB
TDA

S1

L1

Q2

L2
S2

L3

Q4Q3

L4

U14

U13

U23

W1

U2 U5

U9

W2

U4 U11

W3

W4

U1U6

U10

U3

C4

VR1

DS2
DS1

DS3

10

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)

Repeater's transmitter is
turned off after sending a
signal, and the Repeater's
receiver (tied to that
transmitter) is enabled. Some
delay is necessary, since after
the Repeater's transmitter is
turned off, the line still
remains charged for a period
of time. If the receiver were
immediately enabled in a 2-
wire, half-duplex setup, the
Repeater could mistake the
still-charged line for incoming
data, and send that signal to
the transmitter on its other
side.

See Table 3-1 for the setting
that's right for your
application. And see the

Appendix

in this manual for
more on the RS-485 Repeater
delay circuitry.

Fig. 3-2. The Opto-Isolated Repeater Circuit Board.

RJ-45

Connectors

Power

Connector

Optical isolation circuitry

set W1
and W2 to

If your application... position...

has long line-lengths D (35 msec)
and/or many device drops
has moderate line-lengths C (5 msec)
and many device drops
has short line-lengths B (1 msec)
and/or few device drops

is used infrequently A (0.1 msec)

Table 3-1. Setting W1 and W2

D
C
B
A

D
C
B
A

A
B
C

A
B
C

Edge Card
Connector

PORT

J1

PORT

J2

P6

TB1

RDB
RDA

TDB
TDA

A

B

Q2

Q1

TB2

RDB
RDA

TDB
TDA

Q4Q3

W1

D

U2 U5

C
B
A

U9

S1

L1

U14

U18 U16 U17

L2
S2

U13

L3

U23

L4

U4

W2

D
C
B
A

W4
A
B
C

U1U6

U11

U10

U3

A
B
C

W3

U15

C4

VR1

DS2
DS1

DS3

U19

11

CHAPTER 3: Installation

NOTE:

The greater the length of
the RS-485 line and/or the larger
the number of drops on the
network, the longer the line will
remain charged after the
transmitter has been disabled. A
rule of thumb governing how long
to set the delay: The longer the
line/larger the number of devices,
the longer the delay should be.

3. Switches S1 and S2 set the
Repeater's ports for
terminated or unterminated
operation.

To determine if a port
should be terminated or not,
consider where the
Repeater's ports will operate
in your network. If the port
is located at the extreme end
of a network, it should be
terminated. If a port is in
the middle of a network, it
should be left unterminated.

In the ON position, S1
terminates Port A. In the
OFF position, Port A is
unterminated. Termination
is 100 ohms.

When S2 is in the ON
position, Port B is
terminated. In the OFF
position, the associated port
is left unterminated.
(See Fig. 3-5 for an
illustration.)

3.2 Connecting the Repeater to Your
Network.

After the RS-485 Repeater has
been configured for your
application, connect it to your RS-
485 network via either the
Repeater's RJ-45 modular
connectors (J1 and J2 in Figs. 3-1
and 3-2) or the screw-block
terminals (TB1 and TB2 in Figs. 3-
1 and 3-2).

The rest of this chapter describes
how to cable your repeater for
either 2- or 4-wire operation, and
what types of cable you can use.
(See Figs. 3-5 and 3-6 for examples
of how to cable the Repeater
correctly for your network.)

Two- or Four-Wire Operation

To set the Repeater for 2-wire
operation, use a short loop of wire
to connect RDA- to TDA- (this will
be your negative line) and RDB+
to TDB+ (this will be your positive
line) on the repeater's 4-screw
terminal blocks (See Fig. 3-3 for
receive and transmit pins, and for
connecting master and slave
devices in a 2-wire RS-485
network.) Then cable your
network together.

Fig. 3-3. Two-Wire Cabling.

Master Device Slave Device

TDA- RDA-

TDB+ RDB+

RDA- TDA-

RDB+ TDB+

12

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)

To set the Repeater for 4-wire

operation, follow the steps under

Cabling to Your Network

. (See Fig.
3-4 for general information on
connecting master and slave devices
in a 4-wire network.)

Cabling to Your Network

Here are three of the most common
ways to connect the Repeater to
your network:

1.To connect the Repeater to
your network via the terminal
blocks (TB1 and TB2), use
unshielded twisted-pair cable.
(Category 3, 4, or 5 cable is
recommended.) Follow the 4-
screw terminal- block pinning
given in Table A-1 (in the

Appendix

) of this manual and

refer to

Fig. 3-6

for proper
cabling to make sure you
connect each cable to the
correct pin so the Repeater will
communicate properly.

2.To connect the Repeater to
your network via the modular
connectors (J1 and J2), use
either RJ-45 or RJ-11 cables.
Make sure these cables are
pinned both to the repeater
specifications given in Table
A-2 (in the

Appendix

), and to
the specifications of your RS-
485 equipment.

3.If the rest of your RS-485
network conforms to the
RS-530 interface-pinning
standard, you can convert the
repeater's RJ-45 connector to
RS-530 with the optional
adapters listed in Table 3-2.
These are available separately.

Just attach RJ-45 or RJ-11 cable
from the modular connectors
on the Repeater (J1 and J2) to
the adapter's modular
connector. Then attach the
RS-530 cable from the rest of
your network to the other side
of the adapter. Make sure that
the RJ cable you use is straight-
through pinned (that is, Pin 1
at one end of the cable is
connected to Pin 1 on the other
end, Pin 2 to Pin 2, etc.).

Contact our technical support
staff for more information on
using these adapters.

Description of RS-530 side Quote number

DCE female C1CB11564
DCE male C1CB11565
DTE female C1CB11566
DTE male C1CB11567

Table 3-2. Available RJ-45 to RS-530 Adapters

Master Device Slave Device

TDA- RDA­TDB+ RDB+
RDA- TDA­RDB+ TDB+

Fig. 3-4. 4- W ire Cabling.

CHAPTER 3: Installation

13

Fig. 3-5. The RS-485 Repeater in a 2-Wire, Half-Duplex Application.

NOTE:

For more information on RS-485 network performance (signal

speed versus length of the network), refer to Table A-3 in the

Appendix

to

this manual.

PC

IC485

(End of line)

Minus (-) line

Plus (+)

line

Scale

RS-232
Printer

Smart

Node

Bar Code

Reader

Twisted-Pair

Wiring

Port B

(terminated)

RS486 Repeater

(Opto-Isolator)

Port A

(terminated)

Plus

(+) line

Minus (-)

line

RS485

Pump

Conveyor Belt

Lathe Time

Clock

Data

Logger

Terminated

(End of line)

TDA

TDB
RDA
RDB

TDA
TDB

RDA
RDB

RDA
RDB

TDA
TDB

14

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)

Fig. 3-6. Cabling and Signal Flow in F our-Wire, Full- Duplex Operation

NOTE:

As shown in Fig. 3-6, the Repeater is considered a slave device on
the Network 1 side, but the master device on the Network 2 side: By
repeating the signals sent from the master on Network 1, it looks like a
master to the slave devices on Network 2. That's why on Network 1, the
Repeater's data leads are matched up with those of the slave device, but on
Network 2, its receive-data leads are attached to the slave's transmit leads,
and its transmit-data leads are attached to the slave's receive leads.

Master

TXD-

TXD+

RXD-

RXD+

Network 1

RDA-

RDB+

TDA-

RS-485
(Slave)

TDB+

Port A Port B

RDA-

RDB+

TDA-

TDB+

Signal Flow

Signal Flow

TDA­TDB+
RDA­RDB+

Network 2

TDB+

TDA-

RS-485
(Slave)

RDB+

RDA-

Slave

RDA-

RDB+

TDA-

TDB+

Appendix

15

A.1 The RS-485 Repeater Delay
Circuitry

The Repeater uses three different
types of delays: a Turn-around
delay (discussed in

Chapter 3.1

), a
turn-ON delay, and a turn-OFF
delay. See Fig. A-1 for an
illustration of how delay circuitry
operates in the Repeater.

The turn-ON delay

prevents noise

on the RS-485 line from enabling

the Repeater transmitter and being
passed as data. Typically, noise on
the RS-485 line is an electrical
signal of very short duration. If
noise should reach the RS-485
receiver on Port A in Fig. A-1, it
must pass through the carrier
detect, opto-isolation, and delay
circuitry to get to the RS-485
transmitter on Port B. The delay
circuitry has been set at the factory
to delay the enabling of the
Repeater's transmitter long enough
for most noise to dissipate before

RS-485

Receiver

RS-485

Receiver

RS-485

Transmitter

RS-485

Transmitter

Carrier

Detect

Carrier

Detect

Opto-isolation

circuitry

Opto-isolation

circuitry

Turn-ON/
Turn-OFF

delay

Turn-around

delay

(W1 and W2)

Port B

Appendix

Fig. A-1. Repeater Delay Circuitry: A Signal Received at Port A

Propagates Through the Receiver to Port B.

Port A

16

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)

the transmitter is ready to send.
Thus the delay circuitry keeps noise
from being passed along by the
Repeater. The turn-ON delay for
the RS-485 Repeater has been
factory-set to @3.3 µsec.

The turn-OFF delay

keeps the
RS-485 transmitter enabled long
enough for the input data to have
time to propagate through the
Repeater after the sending device
drops the carrier signal. This delay
is 6 µsec.

Here's what happens: when the
transmitting device stops sending,
the Repeater's carrier-detect
circuitry will sense a loss of carrier
and disable the Repeater's
transmitter. At high baud rates, the
transmitter may be disabled before
all the data can propagate through.
Delaying the transmitter-disable for
approximately 6 µsec, ensures that
all of the data propagates through
the Repeater before the transmitter
is disabled.

A.2 Connector Pinning

Table A-1 shows the pinning for the
Repeater's four-screw terminal-
block connectors. Table A-2 shows
the pinning for therepeater's RJ-45
connectors.

Pins Signal

1 RDB+
2 RDA-
3 TDB+
4 TDA-

Table A-1. Terminal Block Pinning

Pins Signal

1 Not connected
2 Not connected
3 RDB+
4 TDB+
5 TDA-
6 RDA-
7 Not connected
8 Not connected

Pins Signal

1 AC voltage in
2 AC voltage in
3 Signal Ground

4 Frame Ground
A TXA
B TXB
E RXA
F RXB

Table A-2. RJ-45Connector Pinning

Table A-3. Edge Card Connector

Pinning

Fig. A-2. RJ-45 Connector.

Table A-3 shows the edge card
connector pinouts. See pages 5 and
6 for the board layouts.

1 2 3 4 5 6 7 8

17

Appendix

A.3 Network Performance

Signal speed on any communication
line is directly dependent on the
distance the signal must travel.
Table A-3 shows speed versus
distance characteristics for a 4-wire
point-to-point application using 24
AWG twisted-pair wiring.

T ableA-4.Data Communication Rates

Speed Distance

in bps in miles (km)

1200 4.0 (6.4)
2400 3.0 (4.8)
4800 2.3 (3.7)

9600 1.7 (2.7)
19,200 1.2 (1.9)
38,400 0.9 (1.4)
64,000 0.8 (1.2)

18

RS-485 Repeater and RS-485 Repeater (Opto-Isolated)Quick Setup Guide

This chapter is designed to help the
experienced user get the RS-485
Repeater installed and running as
quickly as possible. (Figure 3-1 or
3-2 show the location of
components on the Repeater circuit
board.)

Quick Setup Guide

• To set the Repeater to half-
duplex operation:

NOTE:

Half-duplex is the factory-

set default positionfor these components.

Follow these steps for

half-duplex

operation:

Set... to position...

W3 A-B
W4 A-B

Follow these steps for

full-duplex

operation:

• To set the Repeater to full-
duplex operation:

• Next, set the turn-around signal-
response delay with W1 and W2.

set W1
and W2 to

If your application... position...

has long line-lengths D (35 msec)
and/or many device
drops
has moderate line-lengths C (5 msec)
and/or many device drops

has short line-lengths B (1 msec)
and/or few device drops

is used infrequently A (0.1 msec)

Set... to position...

W3 B-C
W4 B-C

1.Power up the
Repeater.

2.Power up your
RS-485
network.

You're ready to go.

• Attach your cables to the
Repeater (see

Chapter 3-2

for

information on cabling).

• To terminate/unterminate Ports:

Port Terminated Unterminated

A S1=ON S1=OFF
B S2=ON S2=OFF