DGH DIN-191, DIN-192 User guide

DIN-191 a n d DI N - 1 9 2 SERIES
CONV E RTER BOXES
USERS MANU A L

REVISED: 8/ 1 2 / 1 3

DGH CORPO R ATIO N
PO BOX 56 3 8
MANCHESTER , NH 03108

T E L E P H O N E: 60 3-6 22 - 0 4 5 2
F A X : 603-6 2 2 - 0 4 8 7
WE B: www. dghco rp.co m

The information in this publication has been carefully checked and is
believed to be accurate; however, no responsibility is assumed for
possible inaccuracies or omissions. Applications information in this
manual is intended as suggestions for possible use of the products and
not as explicit performance in a specific application. Specifications may be
subject to change without notice.

DIN-191 & DIN-192 USERS MANUAL 2

WAR R ANT Y
DGH warrants each DIN-191 and DIN-192 series module to be free from
defects in materials and workmanship under normal conditions of use and
service and will replace any component found to be defective, on its
return to DGH, transportation charges prepaid within one year of its
original pur chase. DGH assumes no liability, expressed or implied,
beyond its obligation to replace any component involved. Such warranty
is in lieu of all other warranties expressed or implied.

RETUR N S
When returning products for any reason, contact the factory and request
a Return Authorization Number and shipping instructions. Write the
Return Authorization Number on the outside of the shipping box. DGH
strongly recommends that you insure the product for value prior to
shipping. Items should not be returned collect, as they will not be
accepted.

Shipping Address:

DGH Corporation
Hillhaven Industrial Park
146 Londonderry Turnpike
Hooksett, NH 03106

3 DIN-191 & DIN-192 USERS MANUAL

GEN E R A L DESCR I PTIO N

The DIN-191 and DIN-192 series converter boxes convert RS-232
communications signal levels to the correct electrical signals required by
RS-485. The RS-485 communications standard is recommended when
many modules, or other addressable devices, must be connected to a
host computer over long distances. The DIN-191 and DIN-192 converters
allow communications bus lengths up to 4,000 meters and baud rates up
to 115K baud using one twisted pair of wires.

The RS-485 communications standard is half-duplex; therefore data can
be transmitted in only one direction at a time. To determine the direction
of data on the RS-485 bus, many products require external handshaking
signals to control the bus direction when transmitting or receiving data.
This technique often requires that host RS-232 software be written, or
modified, to accurately control handshaking signals for proper system
operation. The DIN-191 and DIN-192 automatically control the bus
direction without external handshaking signals from the host. Therefore,
host software written for RS-232 may be used without modification. RS­485 bus control is completely transparent to the user.

The DIN-192 is an RS-485 repeater. Repeaters are required to extend
communications bus lengths or allow more than 32 RS-485 devices to be
connected to a communications bus. A repeater simply re-amplifies, or
boosts, existing RS-485 signals transmitted over long distances.

The DIN-191 and DIN-192 are each isolated between the RS-232 port
and/or RS-485 ports and require a regulated +5Vdc power supply.

DIN-191 & DIN-192 USERS MANUAL 4

SPEC I FICAT I ONS
Max common mode voltage: 500Vrms, 60s duration.
Baud rates: 300, 600, 1200, 2400, 4800, 9600, 19200,
38400, 57600, 115200 (Dip -switch selectable).
Temperature range (operating & storage): -25 to +70°C.
Relative humidity: 0 - 95% noncondensing.
Warranty: 12 months on workmanship and materials.

Po wer Specifi cations
Power requirements: Regulated +5Vdc.
Power consumption: 1.0W Max (RS-485 driver on).

MEC H ANIC A LS AND D IME N SION S
Case: ABS case with screw terminal barrier plug (supplied.
RS-485 Connectors: Phoenix screw terminal barrier plug (supplied).
Replace with Phoenix MSTB 2.5/4 ST 5.08 or equivalent.
Warranty: 12 months on workmanship and materials.

DIN-1 9 1 C O NNECTOR S
The DIN-191 contains two connectors: a four-pin screw terminal plug and
a female DB-9 RS-232 connector.

The four -pin screw terminal plug pin designations are located on the
label of each module. The screw terminals will accept up to #14 gauge
wire (AWG). This connector is used for +5.0Vdc regulated power supply
input and the RS-485 data lines.

5 DIN-191 & DIN-192 USERS MANUAL

The DIN-191 female RS-232 connector utilizes five connections:
Transmit pin 2

Receive pin 3.
Ground pin 5.
Data Set Ready (DSR) pin 6
Clear To Send (CTS) pin 8

Both the Data Set Ready (DSR) input pin #6 and Clear To Send (CTS)
input pin #8 are internally biased to their active state thru a 330Ω resistor
to +5Vdc.

To easily connect to any host PC computer, a straight thru RS-232 cable
can be used. The RS-232 input Ground and signals are isolated by up to
500VRMS from the power supply ground. Cable CA-1 is a male-to-male
DB-9 communications cable available for purchase from us.

Figure 1A Connections for DIN-191.

An RS-485 repeater is necessary to extend the length of an RS-485
network, or connect more than 32 RS-485 devices on an RS-485
network.

The DIN-192 repeater contains a seven-pin screw terminal plug. The pin
designations are located on the label of each module. The screw
terminals will accept up to #14 gauge wire (AWG). This connector is used
for +5.0Vdc regulated power supply input and both pairs of RS-485 data
lines. The isolated RS-485 input data lines are clearly marked and their
ground reference is isolated by up to 500VRMS from the power supply
ground. The isolated RS-485 input data lines should be attached to the
end of an existing RS-485 network. The serial data received on the

DIN-191 & DIN-192 USERS MANUAL 6

isolated RS-485 input data lines will be re-amplified and retransmitted on
the RS-485 OUT data lines.
.

RS-485
Output

RS-485
Input

Figure 1B Connections for DIN-192.

BAUD R A T E
The DIN-191 and DIN-192 series converters contain a 10-position DIP
switch located on the bottom of each unit. The DIP switch is used to
select the correct communications baud rate and must be set to the same
value as the devices connected to the RS-485 data lines. Each position
on the DIP switch is labeled from 1 to 10. Switch position 1 selects 300
baud. Switch positions 2 thru 9 select standard baud rates from 600 to

57.6K respectively. Switch position10 selects 115.2K baud rate. Only
one baud rate switch may be turned on (up position) at one time for
proper operation.

RS-48 5 TE RMIN A T I ONS
The proper termination techniques for any RS-485 system require two
biasing resistors and two termination resistors. The 1kΩ biasing resistors
are connected from the DATA line to +5Vdc and from the DATA* line to
ground. The biasing resistors and are normally positioned at the HOST
end of the cable. The RS-485 standard also requires two resistors across
the data lines for proper termination. Two 220Ω resistors should be
connected between the DATA and DATA* lines. The resistors should be
placed at each end of the RS-485 cable. Please refer to Figure 2 for a
typical RS-485 system application.

The DIN-191 and DIN-192 each contain the b iasing and ter mina tion
resistors necessary to interface any equipment on an RS-485 network.
These resistors are jumper-selectable making it easier to interface the
DIN-191 and DIN-192 to other pieces of equipment that may or may not
contain the biasing and/or termination resistors.

7 DIN-191 & DIN-192 USERS MANUAL

Figure 2. RS-485 biasing & termination resistors.

RS- 485 TERM INAT ION & BIA S ING SETTINGS
Proper termination and biasing of any RS-485 based system can be
performed by properly enabling the correct resistors inside each DIN-191
or DIN-192. Figures 3.0 and 4.0 show the location of the jumpers on the
printed circuit board. The jumpers are shown in their factory set locations
to enable the selected resistors. Insert or remove the jumpers as required
to properly terminate any RS-485 system.

Figure 3. DIN-191 jumper locations.

DIN-191 & DIN-192 USERS MANUAL 8

FIGURE 4. DIN-192 jumper locations.

FACT O RY R S -485 T E RMIN A TION SE TTIN GS
Each DIN-191 and DIN-192 contains internal pin strips for enabling the
internal termination and biasing resistors. Each pc board is clearly marked
with the jumper designators adjacent to each row of pins. The jumper
designators are +1K, 220 and -1K. To enable any resistor, place a jumper
over the pins next to the required designator. The factory switch and
jumper settings are outlined below.

DIN-1 9 1 :
Baud Rate: 300 baud switch up.
Biasing Resistors: +1K, -1K jumpers installed.
Termination Resistor: 220 jumper installed.

DIN-1 9 2 :
Baud Rate: 300 baud switch up.
RS-485 (J3): Biasing Resistors: +1K, -1K jumpers installed.

Termination Resistor: 220 jumper installed.

Isolated RS-485 (J2): Biasing Resistors: +1K, -1K jumpers installed.

Termination Resistor: 220 jumper not installed.