W&T 17633 User manual

Manual
Digital I/O Extender Sets
Type 17633
17634, 17635
Release 1.3
W&T

30
W&T Digital-I/O Extender Sets
© 05/2015 by Wiesemann & Theis GmbH
Subject to error and alteration:
Since it is possible 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 Digital-I/O Extender Sets
Irrtum und Änderung vorbehalten
Although the low bandwidth and large voltage swing of
digital I/O signals make them essentially less sensitive to
external noise than for example serial data signals, in some
case the operating conditions necessitate transmission
procedures which are completely resistant to noise effects
along the transmission line.
Glass fibers used as a transmission medium meet these
requirements ideally while also offering the advantage of
galvanic isolation up to virtually any level between the
connected devices. In installations which are subject to
the risk of severe weather conditions, such as in outdoor
locations or between distant buildings, such a solution
ensures a permanently reliable connection even under adverse
conditions.
Wiesemann & Theis offers a whole family of various glass
fiber interfaces which allow conversion of standard interfaces
into an optical interface for connecting glass fiber cable.
The W&T Digital-I/O Extender Sets, which carry the digital
I/O signals over glass fiber optic cable using a multiplexing
procedure, are described on the following pages along with
the technical data and connection examples.
Up-to-date information about new product developments
can be found in the Internet at http://www.wut.de or in the
e-mail updates from the W&T Interface Club, which you can
sign up for on the W&T homepage.

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W&T Digital-I/O Extender Sets
Table of Contents
Digital-I/O Extender Set 2x2, MM ST, Model 17633 .... 33
Function .............................................................................33
Power Supply and Galvanic Isolation ...................................33
Housing..............................................................................34
Glass Fiber Interface and Digital-I/O Port ............................34
Terminal Assignments ........................................................35
Supply Voltage Input...........................................................35
Digital Inputs......................................................................36
Digital Outputs ...................................................................37
Cable break behavior ..........................................................38
Technical Data ....................................................................39
Digital-I/O Extender Set 8x8, MM ST, Model 17634 .... 41
Function .............................................................................41
System security...................................................................41
Power Supply and Galvanic Isolation ...................................42
Housing..............................................................................42
Glass Fiber Interface and Digital-I/O Port ............................43
LEDs and terminations ........................................................44
Supply Voltage Input...........................................................44
Digital Inputs......................................................................45
Digital Outputs ...................................................................46
Cable break response .........................................................47
Technical Data ....................................................................48
Digital-I/O Extender Set 8x8, SM SC, Model 17635 ..... 49
Function .............................................................................49
System security...................................................................49
Power Supply and Galvanic Isolation ...................................50
Housing..............................................................................50
Glass Fiber Interface and Digital-I/O Port ............................51
LEDs and terminations ........................................................52
Supply Voltage Input...........................................................52
Digital Inputs......................................................................53
Digital Outputs ...................................................................54
Cable break response .........................................................54
Technical Data ....................................................................55

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W&T Digital-I/O Extender Sets
Subject to error and alteration
Digital-I/O Extender Set, Model 17633
Function
The W&T Digital-I/O Extender Set, Model 17633 enables
sending of digital I/O signals bi-directionally over a glass
fiber optic cable.
The set consists of two digital-I/O <> glass fiber optic
converters and supports two I/O channels in each direction.
A special communications protocol between the converters is
used for transmitting over the glass fiber optic cable, so that
the converters can only be used in pairs.
Power Supply
The signal converters are powered by an integrated switched
regulator. This regulator has a variable input voltage range
and enables powering of the converters by using any DC or
AC voltage between 12 and 24 volts. The supply voltage is
reverse polarity protected and can be implemented on the
underside of the converters using the included plug-in 2-pole
screw terminal.
Galvanic Isolation
Within the signal converters the I/O connections are
galvanically isolated from the supply voltage up to min. 1000
V using a DC/DC converter. The level of galvanic isolation
between the two converters and thereby between the I/O
terminal points is determined primarily by the length of the
glass fiber optic cable used.

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W&T Digital-I/O Extender Sets
Housing
The Digital-I/O <> glass fiber optic are integrated inside
a housing for mounting on DIN rails. To configure the
cable break behavior you must open the Interface housing so
that the DIL switches on the Digital-I/O Interface Module are
accessible. To do this, slide the housing cover with the
attached circuit board out of the housing body by grabbing
the ST connector.
Glass Fiber Interface
Common ST connectors are used for connecting the glass
fiber optic cable. A version with SMA connectors is also
available as a special on request.
The light used for data transmission has a wavelength of
820 nm. Common 50/125 µm or 62,5/125 µm multimode
duplex glass fiber optic cable is used, which thanks to its
wide use in networking is easily available and inexpensive.
This means that even existing glass fiber optic sections which
are intended for use in networks can be used for sending
digital signals. Depending on the attenuation factor of the
glass fiber optic cable used, data transmission over distances
of up to 3800 meters is possible.
Digital-I/O Port
The Digital-I/O Port is configured as a plug-in 3.5mm
terminal block so that the connected in- and outputs can be
disconnected from the signal converter at any time without
having to unscrew anything.
All digital inputs use overvoltage-rated components to protect
against transients which exceed the permissible input voltage
of the inputs.

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W&T Digital-I/O Extender Sets
Subject to error and alteration
Driver chips are used for the digital outputs which provide
integrated protection against short circuit, overload and
thermal destruction.
LEDs and Terminal Assignments
The converter features two LED’s, with the Power LED indica-
ting correct supply voltage. The Data LED is not connected.
The configuration of the signal and supply terminals and
the pin configuration of the interfaces can be found on the
device label as well as in the following illustration:
I/O Port
Power
Data
TxD RxD
Fiber Optic Port
Outputs Vdd GND Inputs
1 2 + - 1 2
Vcc
AC/DC
Supply Voltage Input
The supply voltage is connected to the screw terminals on the
underside of the housing.
Any desired voltage of 12V to 24V can be used for power.
Since the signal converters can be operated with DC or AC
voltage, no special precautions are necessary with respect to
the polarity of the supply voltage.
The Vdd terminal on the front side supplies only the
switching outputs and must be connected to a DC voltage. 1

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W&T Digital-I/O Extender Sets
Digital Inputs
The basic wiring of the inputs for the Digital-IO Extender Set
can be seen in the following illustration:
The digital inputs of the Digital-I/O Extender Set 17633 are
„Type 3“ according to IEC 61131-2 and have a maximum input
voltage of 30V with respect to the device reference ground.
The lines to the digital inputs should not be longer than
necessary.
I/O Port
Power
Data
TxD RxD
Fiber Optic Port
Outputs Vdd GND Inputs
1 2 + - 1 2
Vcc
AC/DC
max. 30V DC
+
-
12..24V AC/DC

37
W&T Digital-I/O Extender Sets
Subject to error and alteration
Digital Outputs
The basic wiring of the switching outputs for the Digital-IO
Extender Set can be seen in the following illustration:
The two digital outputs of the Digital-I/O Extenders are
current sourcing. The supply voltage for the outputs may be
between +6 V and +30 V DC and is provided at terminals Vdd
and GND.
Each of the outputs can switch a maximum current of 0.5A.
If loads with an inductive component (e.g. relays, contactors,
solenoids etc.) need to be switched, the outputs must be
additionally protected using recovery diodes.
The outputs have thermal overload protection and are short
circuit protected. In the OFF state a very low current of
approx. 10µA is used to check whether the outputs are
switched to a load. If LEDs are connected to the outputs, this
can result in a slight glow even in the rest state.
I/O Port
Power
Data
TxD RxD
Fiber Optic Port
Outputs Vdd GND Inputs
1 2 + - 1 2
Vcc
AC/DC
+
-
12..24V AC/DC 6.. 30V DC

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W&T Digital-I/O Extender Sets
When sizing the output voltage supply, the required current
must always be taken into consideration. If the selected
voltage for supplying the loads varies between 12V and
24V DC, the signal converter and the switched loads can be
supplied from the same source.
Cable break behavior
Should the glass fiber connection be interrupted or if the
glass fiber cable is not connected, the default response is for
all digital outputs to go directly to the Off state. A different
response can be configured individually for each channel
using DIL switches inside the unit. Simply set the DIL switches
for the corresponding in- and outputs in both Digital-I/O <>
Glass Fiber converters to ON. The names of the DIL switches
In1,In2, Out1 and Out2 can be found on the circuit board
near the switch.
To change for example the
cable break behavior of the
first I/O channel, set DIL
switch In1 on the first inter-
face AND DIL switch Out1
on the second interface to
ON. Now when there is a
cable break or the glass
fiber cable is disconnected,
the output goes directly to
the ON state.
In this way each of the four channels can be configured
individually as desired.
Note: Changing the setting of a DIL switch on only one
Interface causes the signal to be sent inverted. When
voltage is present on the input the corresponding
output is turned off. 1
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