Patton 2017A USER MANUAL

USER
MANUAL

MODEL 2017A

RS-232 to 20ma
Current Loop Converter

SALES OFFICE
[phone]
TECHNICAL SUPPORT
[phone]
http://www.patton.com

Part# 07M2017A-A
Doc# 073021UA
Revised 10/15/93

1.0 WARRANTY INFORMATION

Patton Electronics warrants all Model 2017A components to be
free from defects, and will—at our option—repair or replace the product
should it fail within one year from the first date of shipment.

This warranty is limited to defects in workmanship or materials, and
does not cover customer damage, abuse, or unauthorized modification.
If this product fails or does not perform as warranted, your sole
recourse shall be repair or replacement as described above. Under no
condition shall Patton Electronics be liable for any damages incurred
by the use of this product. These damages include, but are not limited
to, the following: lost profits, lost savings, and incidental or consequen­tial damages arising from the use of or inability to use this product.
Patton Electronics specifically disclaims all other warranties,
expressed or implied, and the installation or use of this product shall be
deemed an acceptance of these terms by the user.

1.1 RADIO AND TV INTERFERENCE

The Model 2017A generates and uses 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 and televi­sion reception. If the Model 2017A does cause interference to radio or
television reception, which can be determined by disconnecting the
power supply, the user is encouraged to try to correct the interference
by one or more of the following measures: moving the computing
equipment away from the receiver, re-orienting the receiving antenna,
and/or plugging the receiving equipment into a different AC outlet (so
the computing equipment and receiver are on different branches).

1.2 SERVICE

All warranty and non-warranty repairs must be returned freight pre­paid and insured to Patton Electronics. All returns must have a Return
Materials Authorization number on the outside of the shipping container.
This number may be obtained from Patton Electronics Technical
Service at [phone].

Packages received without an RMA number

will not be accepted.

Patton Electronics' technical staff is also available to answer any
questions that might arise concerning the installation or use of your
Model 2017A. Technical Service hours: 8AM to 5PM EST, Monday

through Friday.

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2.0 GENERAL INFORMATION

Thank you for your purchase of this Patton Electronics product.
This product has been thoroughly inspected and tested and is warrant­ed for One Year parts and labor.

If any questions or problems arise during installation or use of this
product, please do not hesitate to contact Patton Electronics Customer
Service at [phone].

2.1 FEATURES

• Full duplex, asynchronous transmission over 4 wires

• Operates actively or passively (receiver only; transmitter is active)

• Data rates up to 115,200 bps

• Range to 4 miles on 24 AWG twisted pair

• Optically isolated and surge protected

• LEDs monitor transmit data, receive data and power

• DB-25 male or female connectors on RS-232 side

• Twisted pair connection via terminal block with strain relief,
RJ-11 jack or RJ-45 jack

• External DCE/DTE switch

• Made in the USA

2.2 DESCRIPTION

The Model 2017A RS-232 to 20mA current loop converter lets

an asynchronous RS-232 device communicate with a 20mA current
loop device. Equipped with an external power supply, the Model
2017A supports data rates up to 115,200 bps. The Model 2017A
transmitter is active and must be connected to a passive receiver, and
the Model 2017A receiver can accommodate either a passive transmit­ter or an active transmitter.

Operating full duplex, the Model 2017A supports communication
distances up to 4 miles over two unconditioned 24 AWG twisted pair.
To guard against data loss due to ground loops, the Model 2017A is
equipped with 1500 V RMS optical isolators on the line side.

The Patton Model 2017A connects directly to the RS-232 interface
using a male or female DB-25 connector. An external DCE/DTE
switch eliminates the need for a cross-over cable on the RS-232 inter­face. The Model 2017A is manufactured in the USA.

3.2 SETTING THE ACTIVE/PASSIVE SWITCH

The active/passive switch is used to control the mode of the
receiver; it has no control over the transmitter since the transmitter is
fixed in the active mode.

To configure your Model 2017A receiver, you first need to deter­mine whether your device will be active or passive. If you are going to
use the Model 2017A receiver to source current for the loop, set the
switch to the “active” position. If the Model 2017A is to be used in an
active loop, set the Model 2017A receiver’s active/passive switch to
passive.

WARNING: Never connect two active devices together. Your
configuration must be "active to passive" or "passive to active".

3.0 CONFIGURATION

The Model 2017A is easy to use. The only configuration neces­sary for operation is the proper setting of two switches: the external
DCE/DTE switch and the internal active/passive switch.

3.1 SETTING THE DCE/DTE SWITCH

Figure 1 shows the location of the DCE/DTE switch on the PC
board, as well as the location of the terminal block and surge suppres­sors.

For your convenience, the Model 2017A has an externally acces­sible DCE/DTE switch (see figure 2). If the RS-232 device connected
to the Model 2017A is a modem or multiplexer (or is wired like one),
set the switch to "DTE". This setting causes the Model 2017A to
behave like Data Terminal Equipment, transmitting data on RS-232 pin
2 and receiving data on pin 3.

If the RS-232 device connected to the Model 2017A is a PC, ter­minal or host computer (or is wired like one), set the switch to "DCE".
This setting causes the Model 2017A to behave like Data
Communications Equipment, transmitting data on RS-232 pin 3 and
receiving data on pin 2. Remember: The switch setting is always from
the point of view of the Model 2017A, not the connected equipment.

3 4

+

RCV G XMT

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Figure 1. The Model 2017A

Figure 2. The DCE/DTE switch

Figure 3. The active/passive switch

Terminal

Block

DCE/DTE

Switch

Active/Passive

Switch

TX

RCV

PWR

AC

Adapter

Active

Passive

Active/passive

Switch

DCE DTE