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W&T
Interface modules
Subject to error and alteration
Manual
Interface modules
Model 18801, 18811
18802, 18812
18803, 18813
18601, 18611
18602, 18612
18401, 18411
18402, 18412
18101, 18111
18120, 18121
18311
Version 1.4
W&T
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W&T
Interface modules
© 07/2006 by Wiesemann und Theis GmbH
Subject to error and alteration:
Since it is posssible that we make mistakes, you mustn’t use
any of our statements without verification. Please, inform us of
any error or misunderstanding you come about, so we can
identify and eliminate it as soon as possible.
Carry out your work on or with W&T products only to the
extent that they are described here and after you have
completely read and understood the manual or guide. We are
not liable for unauthorized repairs or tampering. When in
doubt, check first with us or with your dealer.
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W&T
Interface modules
Subject to error and alteration
The modular design of all W&T Com-Servers as well as most of
the W&T PC cards allows them to be equipped with
various serial interface types.
Modification of the standard units is accomplished by
simply exchanging the existing interface modules with
modules of the desired interface type.
The W&T interface module family is described on the
following pages along with the corresponding technical data
and including connection examples.
For up-to-date information on new developments, see our
Internet site at
http://www.wut.de or check the e-mail short
notices at the W&T Interface Club, which you can also
subscribe to from the W&T Homepage.
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Interface modules
Index
Inhalt
Common characteristics and mechanical details ................... 55
RS232 DTE Interface Modules, Model 188x1 ......................... 57
RS232 DCE Interface Modules, Model 188x2 ......................... 59
RS232/RS422/RS485 Interface Modules, Model 188x3 .......... 61
RS422/RS485 Interface Modules, Model 186x1 ..................... 69
Profibus Interface Modules, Model 186x2 ............................ 77
20mA Interface Modules, Model 184x1 ................................ 81
20mA Interface Modules, Model 184x2 ................................ 85
POF Interface Modules, Model 181x1 ................................... 89
Fiber Optic Interface Modules, Model 1812x ........................ 93
USB Interface Module, Model 18311 ..................................... 97
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W&T
Interface modules
Subject to error and alteration
Common characteristics and mechanical details
Many W&T Interfaces are characterized by modular construction
with a strict division into basic and interface electronics, so that
changing out the integrated, plug-in Interface Modules allows
you to freely select the interface type for the device.
In addition you can use the W&T Interface Modules to equip
third-party devices which only have a serial TTL interface with
various standard interfaces: RS232, RS422, RS485, 20mA,
plastic fiber optics, glass fiber optics and USB.
There are two different series of W&T Interface Modules (series
18x0x and 18x1x) which differ only in the arrangement of the
connector for the serial TTL port, but which are otherwise
identical in function.
All W&T Interface Modules have a 12-pin 2mm header and a
central hole for screwing the module to the associated motherboard. The pin configuration for the TTL interface can be found
in the corresponding sections for the individual Module
descriptions.
The position of pin 1 of the header, which is additionally
indicated by a square solder pad, as well as the numbering
order of the connector pins, can be seen for both Module
series in the following diagram:
18x0x
1
6
7
12
18x1x
1
6
7
12
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Interface modules
Dimensional drawing
The following drawing indicates the dimensions of the Module
as well as the position of the connectors and attachment
points. Shown in the drawing is the Combi-Module 18833, but
the dimensions apply to all Modules with SUB-D connector.
Important installation note
When installing or replacing the Interface Modules, visually
inspect to ensure that the module does not cause a short
circuit with adjacent components. To use the Interface
Modules with W&T PC cards, remove the wire jumper between
the SUB-D male connector housing and the module. Otherwise
the galvanic isolation between the interface and the PC may be
defeated.
1
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W&T
Interface modules
Subject to error and alteration
RS232 DTE Interface Modules, #188x1
Function
The W&T Interface Modules 18801 and 18811 provide an
RS232 DTE interface for devices equipped with a serial TTL port.
The modules support all RS232 data and handshaking signals.
Modules 18801 and 18811 differ only in the arrangement of
the post connector for the serial TTL port, and are in every
other respect functionally identical.
Important installation note
When installing or replacing the Interface Modules, visually
inspect to ensure that the module does not cause a short
circuit with adjacent components. To use the Interface Modules with W&T PC cards, remove the wire jumper between the
SUB-D male connector housing and the module. Otherwise the
galvanic isolation between the interface and the PC may be
defeated.
Supply voltage
The Interface Modules require a regulated supply voltage of
5V DC ±5%. The no-load current draw of the modules is
approx. 30mA (typ.); any additional current requirement from
an external load must of course be taken into account when
dimensioning the power supply.
Protection against static charges
All external signal lines use ESD-immune interface components
to provide protection against static discharges of up to 15kV
per IEC 801-2, Level 4.
1
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Interface modules
Pin configuration
The RS232 connection for the modules is configured as a
9-pin male SUB-D connector, with the TTL interface formatted
as 12-pin male post connector. Refer to the following
table for connector pin assignments:
TTL interface RS232 interface
pin# signal function
1 5V ±5% Vcc
2 RI output
3 RxD output
4 TxD input
5 n.c. n.c.
6 CTS output
7 DTR input
8 DSR output
9 RTS input
10 DCD output
11 12V ±10% n.c.
12 GND signal GND
Pin 1 of the TTL interface is indicated by a rectangular soldering pad.
Technical Data
Baud rate: 0..230 KBaud
Data format: any
Supported signals: RxD, TxD, RTS, CTS, DSR, DCD, DTR, RI
ESD immunity: up to 15kV per IEC 801-2,
Level 4 using ESD-immune
interface components
Supply voltage: 5V DC ±5%
Supply current: approx. 30mA
TTL connector: 12-pin, 2mm post connector
RS232 connector: 9-pin male SUB-D connector
Dimensions: 43 x 31 mm
Weight: approx. 10g
Packing list: RS232 DTE Interface Module
pin# signal function
1 DCD input
2 RxD input
3 TxD output
4 DTR output
5 GND GND
6 DSR input
7 RTS output
8 CTS input
9 RI input
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W&T
Interface modules
Subject to error and alteration
RS232 DCE Interface Modules, #188x2
Function
The W&T Interface Modules 18802 and 18812 provide an
RS232 DCE interface for devices equipped with a serial TTL port.
The modules support all RS232 data and handshaking signals.
Modules 18802 and 18812 differ only in the arrangement of
the post connector for the serial TTL port, and are in every
other respect functionally identical.
Important installation note
When installing or replacing the Interface Modules, visually
inspect to ensure that the module does not cause a short
circuit with adjacent components.
Supply voltage
The Interface Modules require a regulated supply voltage of
5V DC ±5%. The no-load current draw of the modules is
approx. 30mA (typ.); any additional current requirement from
an external load must of course be taken into account when
dimensioning the power supply.
Protection against static charges
All external signal lines use ESD-immune interface components
to provide protection against static discharges of up to 15kV
per IEC 801-2, Level 4.
1
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Interface modules
Pin configuration
The RS232 connection for the modules is configured as a
9-pin female SUB-D connector, with the TTL interface formatted
as 12-pin male post connector. Refer to the following
table for connector pin assignments:
TTL interface RS232 interface
pin# signal function
1 5V ±5% Vcc
2 RI input
3 TxD output
4 RxD input
5 n.c. n.c.
6 DTR output
7 CTS input
8 DSR input
9 RTS output
10 DCD input
11 12V ±10% n.c.
12 GND signal GND
Pin 1 of the TTL interface is indicated by a rectangular soldering pad.
Technical Data
Baud rate: 0..230 KBaud
Data format: any
Supported signals: RxD, TxD, RTS, CTS,
DSR, DCD, DTR, RI
ESD immunity: up to 15kV per IEC 801-2,
Level 4 using ESD-immune
interface components
Supply voltage: 5V DC ±5%
Supply current: approx. 30mA
TTL connector: 12-pin, 2mm post connector
RS232 connector: 9-pin female SUB-D connector
Dimensions: 43 x 31 mm
Weight: approx. 10g
Packing list: RS232 DCE Interface Module
pin# signal function
1 DCD output
2 RxD output
3 TxD input
4 DTR input
5 GND GND
6 DSR output
7 RTS input
8 CTS output
9 RI output
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Interface modules
Subject to error and alteration
RS232/RS422/RS485 Interface Modules, #188x3
Function
The W&T Interface Modules 18803, 18813 and 18833
provide an RS232, RS422 or RS485 interface for devices
equipped with a serial TTL port. The Interface Module is
configurable for the various operating modes via an
8-position DIL switch. Modules 18803 and 18813/18833
differ only in the arrangement of the post connector for the
serial TTL port, and are in every other respect functionally
identical.
Important installation note
When installing or replacing the Interface Modules, visually
inspect to ensure that the module does not cause a short
circuit with adjacent components. To use the Interface
Modules with W&T PC cards, remove the wire jumper between
the SUB-D male connector housing and the module. Otherwise
the galvanic isolation between the interface and the PC may be
defeated.
Supply voltage
The Interface Modules require a regulated supply voltage of
5V DC ±5% (18803 and 18813) and 3,3V DC ±5% (18833)
respectively. The no-load current draw of the modules is
approx. 40mA (typ.); any additional current requirement from
an external load must of course be taken into account when
dimensioning the power supply.
Protection against static charges
All external signal lines use ESD-immune interface components
to provide protection against static discharges of up to 15kV
per IEC 801-2, Level 4.
1
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Interface modules
Pin 1 of the TTL interface is indicated by a rectangular soldering pad.
RS232 interface RS422/RS485 interface
Pin configuration
The RS232/RS422/RS485 connection for the modules is
configured as a 9-pin male SUB-D connector, with the TTL
interface formatted as 12-pin male post connector. Refer to the
following table for connector pin assignments:
TTL interface
pin# signal function
1 TXD A output
2 RxD A input
3 DTR A output
4 CTS A input
5 GND GND
6 TXD B output
7 RxD B input
8 DTR B output
9 CTS B input
pin# signal RS232 RS422/485
1 5V ±5% Vcc Vcc
2 RI output "low" level
3 RxD output output
4 TxD input input
5 n.c. n.c. n.c.
6 CTS output output
7 DTR input input
8 DSR output "low" level
9 RTS input input
10 DCD output "low" level
11 12V ±10% n.c. n.c.
12 GND signal GND signal GND
pin# signal function
1 DCD input
2 RxD input
3 TxD output
4 DTR output
5 GND GND
6 DSR input
7 RTS output
8 CTS input
9 RI input
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Interface modules
Subject to error and alteration
Operating modes
The Interface Modules are configurable for the following
modes using DIL switches:
RS232
The Interface Module converts all available TTL data and handshake signals into RS232 signals. This mode provides one RxD
and TxD channel each in the respective direction, along with
six handshake channels (RTS, CTS, DSR, DCD, DTR and RI).
RS422
The Interface Module supports one data and one handshake
channel each (selectable DTR or RTS handshake output). The
RS422 sender/receivers are always active.
RS485
One data channel in each direction is always available in all
RS485 modes. These modes differ only in how the RS485
transceivers are controlled.
RS485 4-wire bus master
In this mode the master uses a conductor pair to send
requests to the slaves, which in turn send their replies to the
master on an additional common conductor pair. The RS485
transceivers are always active in this mode, whereby the master
can always send and is constantly listening for the slaves.
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Interface modules
RS485 4-wire mode with handshake control
The RS485 driver chip is turned on with a TTL Low level on the
„DTR“ or „RTS“ line, whereas a TTL High level on this line puts
the driver in a high-impedance state. The receiving channel in
this mode is always active.
RS485 2-wire mode with handshake control
The RS485 driver chip is turned on with a TTL Low level on the
„DTR“ or „RTS“ line, whereas a TTL High level on this line puts
the driver in a high-impedance state. The receiving channel is
deactivated when the driver is on, and enabled when the driver
is in the high-impedance state.
RS485 4-wire mode with automatic control
The RS485 driver chip is automatically activated whenever data
are output and brought to the high-impedance state when data
output is finished. The receiving channel in this mode is always
active.
RS485 2-wire mode with automatic control
The RS485 driver chip is automatically activated when data are
output and brought to the high-impedance state when data
output is finished. The receiving channel is deactivated when
the driver is turned on, and enabled when the driver is in the
high-impedance state.
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Interface modules
Subject to error and alteration
The DIL switch settings can be found in the following table:
*
*) Terminating the bus system when required.
Important Note
The terminating DIL switches SW6 and SW7 must never be in
the ON position when using the module in RS232 mode. This
will result in a significant increase in the current draw and may
cause the RS232 driver to fail.
1
Operating mode SW1 SW2 SW3 SW4 SW5 SW6 SW7 SW8
RS232 OFF OFF OFF OFF OFF OFF OFF ON
RS422, RS485, 4-wire bus master
DTR handshake
OFF OFF OFF ON OFF
**
OFF
RS422, RS485, 4-wire bus master
RTS handshake
OFF OFF OFF OFF ON
**
OFF
RS485, 4-wire / 2-wire with echo
DTR control
OFF OFF ON ON OFF
**
OFF
RS485, 2-wire without echo
DTR control
ON OFF ON ON OFF
**
OFF
RS485, 4-wire / 2-wire with echo
RTS control
OFF OFF ON OFF ON
**
OFF
RS485, 2-Draht without echo
RTS control
ON OFF ON OFF ON
**
OFF
RS485, 4-wire / 2-wire with echo
automatic control
OFF ON OFF ON OFF
**
OFF
RS485, 2-wire without echo
automatic control
ON ON OFF ON O FF
**
OFF