Black Box IC620A-F User manual

MARCH 1998
IC620A-F IC623A-M
IC620A-M IC624A-F
IC623A-F IC624A-M
RS-232/485 Converter
CUSTOMER SUPPORT INFORMATION
Order toll-free in the U.S. 24 hours, 7 A.M. Monday to midnight Friday: 877-877-BBOX
FREE technical support, 24 hours a day, 7 days a week: Call 724-746-5500 or fax [phone]
Mail order: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018
Web site: www.blackbox.com • E-mail: [email protected]
Code: IC620A
SuperSwitch 8
10/100

1
FCC AND IC STATEMENTS
FEDERAL COMMUNICATIONS COMMISSION
AND
INDUSTRY CANADA
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 communi-
cation. 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 Industry Canada.
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 Industrie Canada.
This unit is certified.

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RS-232/485 CONVERTER
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.

3
NOM STATEMENT
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.
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.

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RS-232/485 CONVERTER
TRADEMARKS
Product names mentioned in this manual may be
trademarks or registered trademarks of their respective
companies and are hereby acknowledged.

5
TABLE OF CONTENTS
CONTENTS
1. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . .6
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . .8
2.1 Description . . . . . . . . . . . . . . . . . . . . . . .8
2.2 Features . . . . . . . . . . . . . . . . . . . . . . . . .9
3. Configuration . . . . . . . . . . . . . . . . . . . . . . . .11
3.1 Accessing the DIP Switches . . . . . . . . .11
3.1.1 DIP Switch S1 Settings . . . . . . . .16
3.1.2 DIP Switch S2 Settings . . . . . . . .18
3.2 Typical Applications . . . . . . . . . . . . . .20
4. Installation 24
4.1 Twisted-Pair Connection . . . . . . . . . . .22
4.1.1 Twisted-Pair Connections
Using Terminal Blocks . . . . . . .23
4.1.2 Twisted-Pair Connection
Using RJ-11 or RJ-45 . . . . . . . . .29
4.2 Wiring for Multipoint Circuits . . . . . .31
4.3 Connection to the EIA/TIA-574
Interface . . . . . . . . . . . . . . . . . . . . . . . .33
4.4 Operating the Converter . . . . . . . . . . .34
Appendix: EIA/TIA-574 Interface . . . . . . . . .35

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RS-232/485 CONVERTER
1. Specifications
Transmission Format — Asynchronous
Data Rate — Up to 115,200 bps
Range — Up to 9 miles (14.4 km)
Serial Interface — EIA/TIA-574 standard RS-232 DCE
Connectors — IC620A-F: (1) DB9 female,
(1) 5-position terminal block,
IC620A-M: (1) DB9 male, (1) 5-position terminal block;
IC623A-F: (1) DB9 female, (1) RJ-11 female,
IC623A-M: (1) DB9 male, (1) RJ-11 female;
IC624A-F: (1) DB9 female, (1) RJ-45 female,
IC624A-M: (1) DB9 male, (1) RJ-45 female
Transmit Line — 2-wire or 4-wire unconditioned,
unshielded, solid core, twisted pair
Transmit Mode — 4-wire, full- or half-duplex;
2-wire half-duplex
Control Signals — DSR turns ON immediately
after the terminal raises DTR; DCD turns ON
after recognizing the receive signal from the line;

7
CHAPTER 1: Specifications
CTS turns ON after the terminal raises RTS
RTS/CTS Delay — 8 msec or “no delay”
Carrier — The carrier is switch-selected either
continuous operation or switched operation,
controlled by RTS
Surge Protection — 600 W power dissipation at 1 ms
Temperature — 32 to 122°F (0 to 50°C)
Humidity — 5 to 95%, noncondensing
Maximum Altitude — 10,000 ft. (304.8 m)
MTBF — 209,384 hours
Power — Draws operating power from EIA/TIA-574
data and control signals; no AC power or batteries
required. If necessary, 6 to 12 VDC can be applied
to pin 9 of the EIA/TIA-574 interface
Size — 2.5"H x 1.2"W x 0.75"D (6.4 x 3.1 x 1.9 cm)
Shipping Weight — 1 lb. (0.5 kg)

8
RS-232/485 CONVERTER
2. Introduction
2.1 Description
The RS-232/485 Converter (IC620A) is an ultra-
miniature interface converter. Requiring no
AC power or batteries for operation, the Converter
supports asynchronous communication up to
115.2 Kbps over one or two unconditioned
twisted pairs. Distances up to 15 miles (24 km)
are attainable at lower data rates (1.2 Kbps,
19 AWG twisted pair).
The Converter can handle up to 31 terminal drops
in a multipoint polling environment. For RS-485
applications that require hardware handshaking, the
Converter passes one control signal in each direction
(see the last bullet point in Section 2.2 for an
explanation). The Converter may be configured for
high or low impedance, and the carrier may be set to
“constantly on” or “controlled by RTS.” The unit can
operate with or without “echo.” RTS/CTS delay may
be set for “no delay” or “8 ms delay.”
There are three options for twisted-pair
connection: terminal blocks with strain relief, RJ-11,
or RJ-45. Silicon Avalanche Diodes provide 600 watts
per wire of protection against harmful data-line
transient surges.

9
CHAPTER 2: Introduction
Six models are available:
• DB9F/Term (IC620A-F)
• DB9M/Term (IC620A-M)
• DB9F/RJ-11 (IC623A-F)
• DB9M/RJ-11 (IC623A-M)
• DB9F/RJ-45 (IC624A-F)
• DB9F/RJ-45 (IC624A-M)
2.2 Features
• Operates asynchronously, point-to-point
or multipoint, over 2 or 4 wires.
• Up to 31 multipoint device drops in a polling
environment.
• Data rates up to 115.2 Kbps.
• Passes transmit and receive data, one control
signal in each direction.
• No AC power or batteries required.
• Variable high/low impedance settings.
• Able to operate with or without “echo.”
• Carrier can be set as “constantly on” or
“controlled by RTS.”

10
RS-232/485 CONVERTER
• Twisted-pair connection via strain relief,
RJ-11, or RJ-45.
• Silicon Avalanche Diode surge protection.
• A Transmitter On signal received at the RS-485
RCV connection will cause DCD output at the
RS-232 connector to assert High.

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CHAPTER 3: Configuration
3. Configuration
The Converter is configured using two internal
4-position DIP switches. This section shows how to
access the DIP switches, provides an overview of the
factory-default settings, and describes all possible
configuration options. For instructions on how to
configure the Converter for specific applications,
see Section 3.2.
3.1 Accessing the DIP Switches
The Converter has a main PC board and a daughter-
board. DIP switch S1 is located on the underside of
the main PC board (see Figure 3-1). DIP switch S2
is located on the top of the daughterboard (see
Figure 3-2).

12
RS-232/485 CONVERTER
Figure 3-1. Underside of the Converter’s main PC board,
showing the location of DIP switch S1.
Switch S1

13
CHAPTER 3: Configuration
Figure 3-2. Top of the Converter’s daughterboard,
showing the location of DIP switch S2.
Switch S2
RCV XMT
G-++-

14
RS-232/485 CONVERTER
To access the Converter’s internal PC boards,
insert a small flat-blade screwdriver between the
connector and the lip of the case and twist gently
as shown in Figure 3-3.
Figure 3-3. Opening the Converter’s plastic case with a small
screwdriver.

15
CHAPTER 3: Configuration
Both DIP switch S1 and S2 are marked with
individual switch numbers 1 through 4. Use these
numbers, and the “ON” designation to orient the
switch properly (see Figure 3-4). Use a small
screwdriver or similar instrument to set each
individual switch.
1 2 3 4
ON
ON
OFF
Figure 3-4. Close-up of DIP switches S1 and S2,
showing ON/OFF orientation.

16
RS-232/485 CONVERTER
3.1.1 DIP S WITCH S1 S ETTINGS
DIP switch S1 is used to configure receive impedance
(termination), 2-wire/4-wire operation and “echo”
enable/disable. Table 3-1 shows the factory-default
settings for switch S1. Following Table 3-1 is a
detailed description of each switch.
Table 3-1. Switch S1 Summary Table (factory defaults in bold)
Position Function OFF Position ON Position
S1-1 RCV impedance (termination) 16 K ohms, typ. 120 ohms
S1-2* 2-wire/4-wire 4-wire 2-wire
S1-3* 2-wire/4-wire 4-wire 2-wire
S1-4 Echo Mode Echo OFF Echo ON
*Switches S1-2 and S1-3 should be switched simultaneously.

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CHAPTER 3: Configuration
S1-1: Receive Impedance (Termination)
The setting for switch S1-1 selects the impedance
of the input receiver. You may select either a “low”
impedance of 120 ohms or a “high” impedance of
16 K ohms. By selecting the proper impedance for
each drop, you can have up to 50 receivers in one
application.
S1-1 Setting
On Low (120 ohms)
Off High (16 K ohms typical)
S1-2 and S1-3: 2-wire/4-wire Modes
Switches S1-2 and S1-3 are set together to determine
whether the Converter is in 2-wire or 4-wire
operating mode.
NOTE
2-wire mode is half-duplex only.
S1-2 S1-3 Setting
On On 2-wire mode
Off Off 4-wire mode

18
RS-232/485 CONVERTER
S1-4: Echo Mode
The setting for switch S1-4 determines whether
the Converter echoes data back to the transmitting
device (half-duplex mode only).
S1-4 Setting
On Echo On
Off Echo Off
3.1.2 DIP S WITCH S2 S ETTINGS
DIP switch S2 is used to configure carrier control,
RTS/CTS delay, and communication protocol. Table
3-2 shows the factory-default settings for switch S2.
Following Table 3-2 is a detailed description of each
individual switch.
Table 3-2. Switch S2 Summary Table (factory defaults in bold)
Position Function OFF Position ON Position
S2-1 Carrier Control Constantly ON ON Position
S2-2 RTS/CTS Delay No Delay 8 msec
S2-3* “XMT Off” impedance High Intermediate
S2-4* “XMT Off” impedance High Intermediate
*Switches S2-3 and S2-4 should be switched simultaneously.

19
CHAPTER 3: Configuration
S2-1: Carrier Control Method
The setting for S2-1 determines whether the carrier
is “Constantly On” or “Controlled by RTS.” This
allows for operation in switched carrier, multipoint,
and/or hardware handshaking applications.
S2-1 Setting
On Controlled by RTS
Off Constantly On
NOTE
When in Controlled mode, RTS must go negative to turn
off the Transmitter and enable the Receiver.
S2-2: RTS/CTS Delay
The setting for switch S2-2 determines the amount of
delay between the time the Converter “sees” RTS and
when it sends CTS.
NOTE
The RTS/CTS Delay setting should be based upon
transmission timing.
S2-2 Setting
On 8 msec
Off No delay