USER
MANUAL
MODEL 2017P
RS-232 to 20mA and
MODEL 2017P60
RS-232 to 60mA
Current Loop Converters
07M2017P-E
Doc# 073051UE
Revised 5/7/96
SALES OFFICE
(301) 975-1000
TECHNICAL SUPPORT
(301) 975-1007
3.0 CONFIGURATION
4.0 INSTALLATION
The Model 2017P is designed to be easy to use. There are no
internal jumpers or DIP switches to set, so there is no need to open the
case to configure the unit (you may need to open the case for wire
connection—refer to Section 4.0). The only configuration necessary for
operation is proper setting of the external DCE/DTE switch.
The Model 2017P is simple to install. After configuring the
DTE/DCE switch, connect the two twisted pairs using one of three
methods: terminal blocks with strain relief, RJ-11 jack or RJ-45 jack.
The method you use will depend on the specific model you have.
The diagram below shows the location of the DCE/DTE switch on
the PC board, as well as the location of the terminal block and surge
suppressors ("S" model only).
4.1 TWISTED PAIR WIRING OVERVIEW
Only one Model 2017P is needed for each RS-232 to 20mA (or
60mA) current loop circuit. The Model 2017P is connected to the
current loop device using two twisted pairs. The pairs must be "dry"
(unconditioned) metallic wire, 19 - 26 AWG. Best distance is achieved
with larger gauges. When you have completed wiring for your data
circuit, the pin connections should be as shown below:
DCE/DTE
Switch
Terminal
Block
XMT +
XMT -
G
RCV +
RCV -
RCV+
RCV -
G
XMT +
XMT -
One Pair
One Pair
}
}
Opto
Isolator
To Shield (Optional)
Opto
Isolator
4.1.1 TWISTED PAIR CONNECTION USING TERMINAL BLOCKS
3.1 SETTING THE DCE/DTE SWITCH
The terminal block/strain relief version of the Model 2017P allows
you to hook up the line side interface using bare wires. The following
instructions will tell you how to open the case, connect the bare wires
and fasten the strain relief collar in place.
For your convenience, the Model 2017P has an externally
accessible DCE/DTE switch (see diagram below). If the RS-232 device
connected to the Model 2017P is a modem or multiplexer (or is wired
like one), set the switch to "DTE". This setting causes the Model 2017P
to behave like Data Terminal Equipment and transmit data on pin 2.
1. Open the unit by gently inserting a screw driver between the
DB-25 connector and the lip of the plastic case (see below). You don't
have to worry about breaking the plastic, but be careful not to bend the
D-sub connector.
If the RS-232 device connected to the Model 2017P is a PC,
terminal or host computer (or is wired like one), set the switch to "DCE".
This setting causes the Model 2017P to behave like Data
Communications Equipment and transmit data on pin 3.
DCE
DTE
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4
6. If there is a shield around the telephone cable, it may be
connected to "G" on the terminal block. To avoid ground loops, we
recommend connecting the shield at the computer end only. A ground
wire is not necessary for proper operation of these units.
7. When you finish connecting the wires to the terminal block, the
assembly should resemble the diagram below:
Once the unit has been opened, you will be able to see the
terminal blocks located at the rear of the PC board.
2. Strip the outer insulation from the twisted pairs about one inch
from the end.
8. Place the 2 halves of the strain relief assembly on either side of
the telephone wire and press together very lightly. Slide the assembly
so that it is about 2 inches from the terminal posts and press together
firmly. If your cable diameter is too small or too large for our strain
relief, please contact our technical support. We have strain relief
assemblies to accommodate most cable diameters.
3. Strip back the insulation on each of the 2 twisted pair wires
about .25".
4. Connect one pair of wires in the telephone cable to "XMT"
(Transmit) on the terminal block, being careful to observe the polarity.
(The wire connected to "XMT+"must be connected at the other end of
the telephone line to "RCV+" in the other unit and the wire connected to
"XMT-" must be connected at the other end of the telephone line to
"RCV-" in the other unit).
5. Connect the other pair of wires in the telephone cable to "RCV"
(Receive), again being careful to observe the polarity. (The wire
connected to "RCV+" must be connected at the other end of the
telephone line to "XMT+" in the other unit and the wire connected to
"RCV-" must be connected at the other end of the telephone line to
"XMT-" in the other unit).
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4.1.2 TWISTED PAIR CONNECTION USING MODULAR JACKS
9. Insert the strain relief assembly with the wire going through it
into the slot in the bottom half of the modem case and set it into the
recess in the case.
The modular versions of the Model 2017P have an RJ-11 or RJ-45
jack mounted in the case. These jacks are prewired for a standard
TELCO wiring environment. To be sure you have the right wiring, use
the table below as a guide.
RJ-11
SIGNAL
RJ-45
SIGNAL
1----------------GND†
2----------------RCV-
3----------------XMT+
4----------------XMT-
5----------------RCV+
6----------------GND
1 --------------N/C
2 --------------GND
3 --------------RCV-
4 --------------XMT+
5 --------------XMT-
6 --------------RCV+
7 --------------GND
8 --------------N/C
†Connection to ground is optional
10. BEND the top half of the case as necessary to place it over the
strain relief assembly. Do not snap the case together yet.
1 - Blue
2 - Orange
3 - Black
4 - Red
1 - Blue
2 - Yellow
3 - Green
4 - Red
5 - Green
6 - Yellow
7 - Brown
8 - Slate
5 - Black
6 - White
AT&T standard modular color codes
4.2 COMPLETING THE INSTALLATION
Once you have configured the unit for DTE or DCE and connected
the twisted pair wires correctly, simply plug the Model 2017P into the
RS-232 data port. Remember to insert and tighten the two captive
connector screws.
11. Insert one captive screw through a saddle washer and then
insert the captive screw with the washer on it, through the hole in the
DB-25 end of the case. Snap that side of the case closed. Repeat the
process for the other side. This completes the cable installation
process.
The Model 2017P requires no power supply or batteries for
operation. It will work automatically at any data rate from 50 to 19,200
bps, as long as there is any data or control voltage being applied.
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APPENDIX A
APPENDIX B
SPECIFICATIONS
RS-232C PIN CONFIGURATIONS
Transmission Line: 19 to 26 AWG twisted pair
DIRECTION
STANDARD "DCE" SETTING
DIRECTION
Range: 4 miles on 24 AWG twisted pair
1- (FG) Frame Ground
2- (TD) Transmit Data
3- (RD) Receive Data
4- (RTS) Request to Send
5- (CTS) Clear to Send
6- (DSR) Data Set Ready
7- (SG) Signal Ground
To Mdl 2017P
From Mdl 2017P
To Mdl 2017P
Interfaces: Asynchronous, EIA RS-232, CCITT V.24 full duplex,
20mA current loop (Model 2017P60 connects to 60mA current loop)
From Mdl 2017P
From Mdl 2017P
Data Rates: 0 - 115.2 Kbps
To Mdl 2017P
Data Term. Ready (DTR) - 20
8- (DCD) Data Carrier Detect
From Mdl 2017P
Isolation: 2500V RMS via opto-isolators
Surge Suppression: Over-voltage protection for opto-isolators via
Silicon Avalanche Diodes
Connectors: DB-25 male or female on RS-232 side; RJ-11, RJ-45
or terminal block with strain relief on current loop side
DIRECTION
STANDARD "DTE" SETTING
DIRECTION
Power Supply: No external power required; uses power from NIC
data signals
1- (FG) Frame Ground
2- (TD) Transmit Data
3- (RD) Receive Data
From Mdl 2017P
To Mdl 2017P
From Mdl 2017P
To Mdl 2017P
To Mdl 2017P
Temperature Range: 0-50°C (32-122°F)
Altitude: 0-15,000 feet
4- (RTS) Request to Send
5- (CTS) Clear to Send
6- (DSR) Data Set Ready
7- (SG) Signal Ground
8- (DCD) Data Carrier Detect
Humidity: Up to 95% non-condensing
Dimensions: 2.50"L x 1.2"H x 0.75"W
Weight: 1.5 oz
From Mdl 2017P Data Term. Ready (DTR) - 20
To Mdl 2017P
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APPENDIX C
BLOCK DIAGRAM
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