Remote Automation Solutions Bristol Isolated RS-485 Interface Boards Manuals & Guides

Product Information Package

PIP-ISORS485

Mar., 2007

Series 33XX, 3508-XX-X, 3530-XX-X & 3808-XX-X

Isolated RS-485 Interface Board

For The Following Bristol Instruction Manuals:
CI-3305, CI-3310, CI-3330, CI-3335
CI-3508-XXX, CI-3530-XXX & CI-3808

www.EmersonProcess.com/Bristol

IMPORTANT! READ INSTRUCTIONS BEFORE STARTING!

Be sure that these instructions are carefully read and understood before any
operation is attempted. Improper use of this device in some applications may result in
damage or injury. The user is urged to keep this book filed in a convenient location for
future reference.

These instructions may not cover all details or variations in equipment or cover
every possible situation to be met in connection with installation, operation or main­tenance. Should problems arise that are not covered sufficiently in the text, the pur­chaser is advised to contact Bristol for further information.

EQUIPMENT APPLICATION WARNING

The customer should note that a failure of this instrument or system, for
whatever reason, may leave an operating process without protection. Depending upon
the application, this could result in possible damage to property or injury to persons.
It is suggested that the purchaser review the need for additional backup equipment
or provide alternate means of protection such as alarm devices, output limiting, fail­safe valves, relief valves, emergency shutoffs, emergency switches, etc. If additional
in-formation is required, the purchaser is advised to contact Bristol .

RETURNED EQUIPMENT WARNING

When returning any equipment to Bristol for repairs or evaluation, please note
the following: The party sending such materials is responsible to ensure that the
materials returned to Bristol are clean to safe levels, as such levels are defined and/or
determined by applicable federal, state and/or local law regulations or codes. Such
party agrees to indemnify Bristol and save Bristol harmless from any liability or
damage which Bristol may incur or suffer due to such party's failure to so act.

ELECTRICAL GROUNDING

Metal enclosures and exposed metal parts of electrical instruments must be
grounded in accordance with OSHA rules and regulations pertaining to "Design
Safety Standards for Electrical Systems," 29 CFR, Part 1910, Subpart S, dated: April
16, 1981 (OSHA rulings are in agreement with the National Electrical Code).

The grounding requirement is also applicable to mechanical or pneumatic in­struments that include electrically-operated devices such as lights, switches, relays,
alarms, or chart drives.

EQUIPMENT DAMAGE FROM ELECTROSTATIC DISCHARGE VOLTAGE

This product contains sensitive electronic components that can be damaged by
exposure to an electrostatic discharge (ESD) voltage. Depending on the magnitude
and duration of the ESD, this can result in erratic operation or complete failure of the
equipment. Read supplemental document S14006 at the back of this manual for
proper care and handling of ESD-sensitive components.

Bristol 1100 Buckingham Street, Watertown, CT 06795

Telephone [phone]

WARRANTY

A. Bristol warrants that goods described herein and manufactured by Bristol are free

from defects in material and workmanship for one year from the date of shipment
unless otherwise agreed to by Bristol in writing.

B. Bristol warrants that goods repaired by it pursuant to the warranty are free from

defects in material and workmanship for a period to the end of the original warranty
or ninety (90) days from the date of delivery of repaired goods, whichever is longer.

C. Warranties on goods sold by, but not manufactured by Bristol, are expressly limited

to the terms of the warranties given by the manufacturer of such goods.

D. All warranties are terminated in the event that the goods or systems or any part

thereof are (i) misused, abused or otherwise damaged, (ii) repaired, altered or
modified without Bristol's consent, (iii) not installed, maintained and operated in
strict compliance with instructions furnished by Bristol, or (iv) worn, injured or
damaged from abnormal or abusive use in service time.

E. THESE WARRANTIES ARE EXPRESSLY IN LIEU OF ALL OTHER

WARRANTIES EXPRESS OR IMPLIED (INCLUDING WITHOUT LIMITATION
WARRANTIES AS TO MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE), AND NO WARRANTIES, EXPRESS OR IMPLIED, NOR ANY
REPRESENTATIONS, PROMISES, OR STATEMENTS HAVE BEEN MADE BY
BRISTOL UNLESS ENDORSED HEREIN IN WRITING. FURTHER, THERE ARE
NO WARRANTIES WHICH EXTEND BEYOND THE DESCRIPTION OF THE
FACE HEREOF.

F. No agent of Bristol is authorized to assume any liability for it or to make any written

or oral warranties beyond those set forth herein.

A. Buyer's sole remedy for breach of any warranty is limited exclusively to repair or

replacement without cost to Buyer of any goods or parts found by Seller to be
defective if Buyer notifies Bristol in writing of the alleged defect within ten (10) days
of discovery of the alleged defect and within the warranty period stated above, and if
the Buyer returns such goods to Bristol's Watertown office, unless Bristol's Water­town office designates a different location, transportation prepaid, within thirty (30)
days of the sending of such notification and which upon examination by Bristol
proves to be defective in material and workmanship. Bristol is not responsible for
any costs of removal, dismantling or reinstallation of allegedly defective or defective
goods. If a Buyer does not wish to ship the product back to Bristol, the Buyer can
arrange to have a Bristol service person come to the site. The Service person's
transportation time and expenses will be for the account of the Buyer. However,
labor for warranty work during normal working hours is not chargeable.

B. Under no circumstances will Bristol be liable for incidental or consequential

damages resulting from breach of any agreement relating to items included in this
quotation, from use of the information herein or from the purchase or use by Buyer,
its em-ployees or other parties of goods sold under said agreement.

REMEDIES

How to return material for Repair or Exchange

Before a product can be returned to Bristol for repair, upgrade, exchange, or to verify
proper operation, form (GBU 13.01) must be completed in order to obtain a RA (Return
Authorization) number and thus ensure an optimal lead time. Completing the form is very
important since the information permits the Bristol Repair Dept. to effectively and
efficiently process the repair order.

You can easily obtain a RA number by:

A. FAX
Completing the form (GBU 13.01) and faxing it to [phone]. A Bristol Repair

Dept. representative will return call (or other requested method) with a RA number.

B. E-MAIL
Accessing the form (GBU 13.01) via the Bristol Web site (www.bristolbabcock.com)

and sending it via E-Mail to [e-mail]
representative will return E-Mail (or other requested method) with a RA number.

C. Mail
Mail the form (GBU 13.01) to

Bristol Inc.
Repair Dept.
1100 Buckingham Street
Watertown, CT 06795

A Bristol Repair Dept. representative will return call (or other requested method)

with a RA number.

D. Phone

Calling the Bristol Repair Department at [phone]. A Bristol Repair Depart-

ment representative will record a RA number on the form and complete Part I, then
send the form to the Customer via fax (or other requested method) for Customer
completion of Parts II & III.

A copy of the completed Repair Authorization Form with issued RA number should be in­cluded with the product being returned. This will allow us to quickly track, repair, and
return your product to you.

. A Bristol Repair Dept.

Bristol Repair Authorization Form (off-line completion)

(Providing this information will permit Bristol to effectively and efficiently process your retu rn. Completion is required to

receive optimal lead time. Lack of information may result in increased lead times.)

Date___________________ RA #___________________SH Line No.____________
Standard Repair Practice is as follows: Variations to this is

practice may be requested in the “Special Requests” section.

• Evaluate / Test / Verify Discrepancy

• Repair / Replace / etc. in accordance with this form

• Return to Customer

Part I Please complete the following information for single unit or multiple unit returns

Address No. (office use only) Address No. (office use only)
Bill to : Ship to:

Purchase Order: Contact Name:____________________________________
Phone: Fax: E-Mail:

Part II Please complete Parts II & III for each unit returned

Model No./Part No. Description

Please be aware of the Non warranty standard charge:

• There is a $100 minimum evaluation charge, which is

applied to the repair if applicable (√ in “returned”
B,C, or D of part III below)

Range/Calibration S/N
Reason for return

: Failure Upgrade Verify Operation Other

1. Describe the conditions of the failure (Frequency/Intermittent, Physical Damage, Environmental Conditions,

Communication, CPU watchdog, etc.)

(Attach a separate sheet if necessary)

2. Comm. interface used: Standalone RS-485 Ethernet Modem (PLM (2W or 4W) or SNW) Other:______________

3. What is the Firmware revision? _____________________ What is the Software & version?

Part III If checking “replaced” for any question below, check an alternate option if replacement is not available

A. If product is within the warranty time period but is excluded due

to Bristol’s warranty clause, would you like the product:

repaired returned replaced scrapped?

B. If product were found to exceed the warranty period,
would you like the product:

C. If product is deemed not repairable would you like your product:
D. If Bristol is unable to verify the discrepancy, would you like the product:

repaired returned replaced scrapped?

returned replaced scrapped?
returned replaced *see below?

* Continue investigating by contacting the customer to learn more about the problem experienced? The person to contact

that has the most knowledge of the problem is: ______________________________ phone_____________________

If we are unable to contact this person the backup person is: _________________________
Special Requests: ____________________________________________________________________________________

phone_____________________

____________________________________________________________________________________________________

Ship prepaid to: Bristol Inc., Repair Dept., 1100 Buckingham Street, Watertown, CT 06795

Phone: [phone] Fax: [phone] Form GBU 13.01 Rev. C 04/27/06

Bristol

Training

GET THE MOST FROM YOUR BRISTOL

BABCOCK INSTRUMENT OR SYSTEM

• Avoid Delays and problems in getting your system on-line

• Minimize installation, start-up and maintenance costs.

• Make the most effective use of our hardware and software.

• Know your system.

As you know, a well-trained staff is essential to your operation. Bristol Inc. offers a full
schedule of classes conducted by full-time, professional instructors. Classes are offered
throughout the year at three locations: Houston, Orlando and our Watertown, CT
headquarters. By participating in our training, your personnel can learn how to install,
calibrate, configure, program and maintain any and all Bristol products and realize the full
potential of your system.

For information or to enroll in any class, contact our training department in Watertown at
[phone]. For Houston classes, you can also contact our Houston office, at (713) 685-

6200.

A Few Words About Bristol Inc.

For over 100 years, Bristol® has been providing innovative solutions for the measurement
and control industry. Our product lines range from simple analog chart recorders, to
sophisticated digital remote process controllers and flow computers, all the way to turnkey
SCADA systems. Over the years, we have become a leading supplier to the electronic gas
measurement, water purification, and wastewater treatment industries.

On off-shore oil platforms, on natural gas pipelines, and maybe even at your local water
company, there are Bristol Inc. instruments, controllers, and systems running year-in and
year-out to provide accurate and timely data to our customers.

Getting Additional Information

In addition to the information contained in this manual, you may receive additional assis­tance in using this product from the following sources:

Help Files / Release Notes

Many Bristol software products incorporate help screens. In addition, the software typically
includes a ‘read me’ release notes file detailing new features in the product, as well as other
information which was available too late for inclusion in the manual.

Contacting Bristol Inc. Directly

Bristol's world headquarters is located at 1100 Buckingham Street, Watertown,
Connecticut 06795, U.S.A.

Our main phone numbers are:

[phone]
[phone] (FAX)

Regular office hours are Monday through Friday, 8:00AM to 4:30PM Eastern Time,
excluding holidays and scheduled factory shutdowns. During other hours, callers may leave
messages using Bristol's voice mail system.

Telephone Support - Technical Questions

During regular business hours, Bristol's Application Support Group can provide telephone
support for your technical questions.

For technical questions about TeleFlow products call [phone].

For technical questions about ControlWave call [phone] or [phone].

For technical questions regarding Bristol’s OpenEnterprise product, call [phone]
or e-mail: [e-mail]

For technical questions regarding ACCOL products, OpenBSI Utilities, UOI and all other
software except for ControlWave and OpenEnterprise products, call [phone].

For technical questions about Network 3000 hardware, call [phone].

You can e-mail the Application Support Group at: [e-mail]

The Application Support Group maintains an area on our web site for software updates and
technical information. Go to: www.bristolbabcock.com/services/techsupport/

For assistance in interfacing Bristol hardware to radios, contact Bristol’s Communication
Technology Group in Orlando, FL at [phone] or [phone].

You can e-mail the Communication Technology Group at:

[e-mail]

Telephone Support - Non-Technical Questions, Product Orders, etc.

Questions of a non-technical nature (product orders, literature requests, price and delivery
information, etc.) should be directed to the nearest sales office (listed on the rear cover of
this manual) or to your Bristol-authorized sales representative.

Please call the main Bristol Inc. number (860-945-2200) if you are unsure which office
covers your particular area.

Visit our Site on the World Wide Web

For general information about Bristol Inc. and its products, please visit our site on the
World Wide Web at: www.bristolbabcock.com

Training Courses

Bristol’s Training Department offers a wide variety of courses in Bristol hardware and
software at our Watertown, Connecticut headquarters, and at selected Bristol regional
offices, throughout the year. Contact our Training Department at [phone] for course
information, enrollment, pricing, and scheduling.

PIP-ISORS485

ISOLATED RS-485 INTERFACE BOARD

PT. NO. 392909-XX-X

TABLE OF CONTENTS

TITLE PAGE #

DESCRIPTION

Function.................................................................................................................................... 1

Features.................................................................................................................................... 1

COMPONENT IDENTIFICATION

Two-Wire End Node Jumpers W1, W3 & W4.......................................................................... 3

Four-Wire End Node Jumpers W2, W5 & W6......................................................................... 3

Connectors ................................................................................................................................ 4

Switches.................................................................................................................................... 5

Indicators.................................................................................................................................. 5

WIRING

RS-232 Interface Between Isolated RS-485 Intf. Board and the Host Node .......................... 5

RS-485 Interface Between Isolated RS-485 Intf. Board and the Host Node .......................... 6

Isolated RS-485 Port Interface to LAN.................................................................................... 6

Field Terminations for RS-485................................................................................................. 6

ISOLATED RS-485 INTERFACE BOARD SPECIFICATIONS

Performance Specifications ......................................................................................................9

Environmental Specifications .................................................................................................. 9

Part Numbers ........................................................................................................................... 9

SUPPLEMENTS

Special Instructions for Class I, Division 2 Hazardous Locations ............................................... Appendix A

PIP-ISORS485 Page 0-1 Table Of Contents

ISOLATED RS-485 INTERFACE BOARD

DESCRIPTION

Function

An Isolated RS-485 Interface Board allows any Bristol Network 3000 product to com­municate over an isolated master/salve network. Each node on the network that incur­porates an Isolated RS-485 Interface Board is optically isolated from the rest of the
network, thereby eliminating ground loop and potential difference effects that may degrade
network communication performance. The result is a reliable communication medium for
in-plant or building to building LANs. The Isolated RS-485 Board effectively replaces the
Network Interface Box (NIB).

Features

• On-Board Power Supply
A power supply, operating from a bulk +9 to +35 VDC source, powers the RS-485
circuitry, generating a regulated 5VDC. A 30V transient Voltage Suppresser provides
over-voltage protection on the input terminals. A separate IC provides the -5VDC
required by the RS-232 transceiver. Bulk DC power is interfaced to the board on
Connector TB1. The + DC Bulk is connected to TB1 Pin 1 and the VDC Return or
Ground is supplied to TB1 Pin 2. TB1 Pin 3 is not used.

• Optical Isolation

Optically Isolated 2-Wire or 4-Wire RS-485 circuits with 300VDC isolation eliminates
ground loops and potential difference effects.

• 100Ω Isolated RS-485 Termination For 2\4-Wire Boards & Receiver Biasing

Installation of Jumper W1 is required at each Isolated RS-485 Board associated with
an end node of a Two-wire or Four-wire RS-485 network. In the case of a Four-wire RS­485 network, the Isolated RS-485 Board’s Jumper W2 must also be installed at each
end node. Units installed at the master node of a 2-wire RS-485 network must also
have Jumper W3 (Receiver Bias to Isolated Ground) & Jumper W4 (Receiver Bias to
Isolated VCC) installed, while units installed at the master node of a 4-wire RS-485
network must also have Jumper W5 (Receiver Bias to Isolated Ground) & Jumper W6
(Receiver Bias to Isolated VCC) installed (See Section - End Node Jumpers W1 through
W6).

• RS-232 or RS-485 Node Interfaces

Networks nodes may connect to the Isolated RS-485 Interface Board via an RS-232 or
RS-485 interface. For installations where each node will include its own Isolated RS­485 Interface Board and asynchronous operation is required (38.4 KBaud max) an RS­232 interface may be used. In situations where several nodes will be mounted in close
proximity, as in an equipment cabinet containing two or more DPCs, a single Isolated
RS-485 Interface Board may be employed by multidropping to each slave using the RS­485 Interface Connector TB3. For LANs that will operate synchronously (187.5 KBaud
to 1 MBaud), all nodes are required to have an RS-485 interface. As with the isolated
LAN itself, up to 32 nodes can be included in a multidrop arrangement. The maximum
distance between communicating nodes on a 2-wire 187.5 KBaud LAN is approximately

PIP-ISORS485 Page 1 Isolated RS-485 Interface Board

1000 feet (300 meters). The maximum distance between communicating nodes on a 4­wire 1 MBaud LAN is approximately 200 feet (60 meters).

• Surge Protection

Surge suppression on input ports and on the isolated output port meets IEC-801 to
isolated ground.

• Isolated RS-485 Common-Mode Voltage Range
The Isolated RS-485 Port features -7V to +12V common-Mode Input Voltage range with
respect to Isolated ground. The port also includes current limiting and thermal
shutdown circuitry for driver overload protection.

• Switch Selectable Termination, Operating Mode, and 2/4-Wire Configuration
8 position DIP switches S1 and S2 are used to configure the Isolated RS-485 Board’s
various operating parameters associated with port usage and LAN configuration.

• Mounting

The Isolated RS-485 Interface Board measures 4.302” (10.917cm) in width x 4.230”
(10.744cm) in height and may be mounted externally or to the top of an RTU 3305 via a
DIN Rail and DIN Rail Mounting Base. When mounted in a DIN Rail Mounting Base
the unit measures 4.375” (12.112cm) in width x 4.375” (12.112cm) in height.

• PC LAN Functionality
The RS-232 Interface port allows PCs (which only have an RS-232 port) to be net­worked over an Isolated RS-485 LAN at asynchronous communication rates.

Figure 1 - Isolated RS-485 Board Component Identification Diagram

PIP-ISORS485 Page 2 Isolated RS-485 Interface Board

COMPONENT IDENTIFICATION

The Isolated RS-485 Interface Board has four wiring connectors; J1, TB1, TB2 and TB3,
two configuration switches; S1 and S2, six 2-pin end node configuration jumpers; W1
through W6. Jumpers W1, W3 and W4 are used in on 2-wire networks and Jumpers W1,
W2, W5 & W6 are used on 4-wire networks. The board is protected by an on-board fuse F1
that is rated at .25A.

Figure 2 - Isolated RS-485 Board in a DIN Rail Mounting Base

Two-Wire End Node Jumpers W1, W3 & W4

Jumpers should be placed in an open position, i.e., installed on pin 1 or pin 2 for all nodes
except the end nodes. Jumper W1 provides a 100-Ohm termination across TXD/RXD- and
TXD/RXD+ at the most distant (end) nodes. Two-wire RS-485 LANs also require the use of
jumper W3 to provide Tx\Rx bias to isolated ground and jumper W4 to provide Tx\Rx bias
to isolated VCC. Jumpers W3 and W4 are only required at the Master Node (see Table 1
and Figure 3).

Four-Wire End Node Jumpers W2, W5 & W6

Jumpers should be placed in an open position, i.e., installed on pin 1 or pin 2 for all nodes
except the end nodes. Jumper W2 provides a 100-Ohm termination across RXD- and RXD+
at the most distant (end) nodes. On these networks, W5 provides receiver bias to isolated

PIP-ISORS485 Page 3 Isolated RS-485 Interface Board

ground and W6 provides receiver bias to Isolated VCC. Four-wire networks use W2, W5 and
W6 at the master node and W2 at the other end node, unless the network is to operate at
other than 1Mbaud (synchronous), in which case jumpers W5 & W6 must also be installed
at both end nodes (see Table 1 and Figure 4).

Table 1 - End Node Jumper Assignment

Network

Type

RS-485 - 2-Wire W1, W3, W4 W1
RS-485 - 4-Wire - 1Mbaud W2, W5, W6 W2
RS-485 - 4-Wire - Not 1Mbaud W2, W5, W6 W2, W5, W6

Master Node

Jumpers Installed

Last Node (Slave

Jumpers Installed

Connectors

When Connector J1 (9-Pin D-Type) of the Isolated RS-485 Interface Board is connected to a
DPC/RTU, transmitter or computer communications D-Type Connector, an RS-232
interface is established. Connector TB3 of the Isolated RS-485 Interface Board is a 6-Pin
Terminal Block that accommodates interface to an RS-485 port. RS-485 Input Connector
TB3 can be multidropped with up to 32 other RS-485 ports. Connector TB2 provides an
interface to a 2-wire or 4-wire isolated RS-485 network. Input power is provided on
Terminal Block TB1. Tables 2 through 5, which follow, provide a description of each
connector’s functionality:

Table 2 - Power Connector TB1 Wiring List

Pin # Signal Name Description

1 +VDC Input +9V to +35V DC Bulk
2 VDC Return Bulk Return/Ground
3 Not Used N/A

Table 3 - Isolated RS-485 Port Interface Connector TB2 Wiring List

Pin # Signal Name Description

1 TXD/RXD+ (2-Wire)

TXD+ (4-Wire)

2 TXD/RXD-(2-Wire)

TXD- (4-Wire)
3 RXD+ (4-Wire) RXD+ Signal on 4-wire circuits
4 RXD- (4-Wire) RXD- Signal on 4-wire circuits
5 Isolated GND Isolated Ground
6 Chassis GND Chassis Ground

Table 4 - RS-232 Input Port Interface Connector J1 Wiring List

Pin # Signal Name Description

2 TXD RS-232 Transmit Data
4 RXD RS-232 Receive Data
5 RTS RS-232 Request To Send
9 GND RS-232 Ground

Note: Connector Pins 1, 3, 6, 7 & 8 are not used on Connector J1

TXD/RXD+ Signal on 2-wire circuits
TXD+ Signal on 4-wire circuits
TXD/RXD- Signal on 2-wire circuits
TXD- Signal on 4-wire circuits

PIP-ISORS485 Page 4 Isolated RS-485 Interface Board

Table 5 - TB3 RS-485 Input Port Interface Connector TB3 Wiring List

Pin # Signal Name Description

1 TXD+ RS-485 Input Interface Signal Transmit Data Plus (+)
2 TXD- RS-485 Input Interface Signal Transmit Data Minus (-)
3 RXD+ RS-485 Input Interface Signal Receive Data Plus (+)
4 RXD- RS-485 Input Interface Signal Receive Data Minus (-)
5 RTS+ RS-485 Input Interface Signal Request To Send Plus (+)
6 RTS- RS-485 Input Interface Signal Request To Send Minus (-)

Switches

Two eight position DIP Switches are provided for board and network configuration. The
functionality of these switches are provided in Tables 6 and 7 below:

Table 6 - Switch S1 Configuration Settings

Position Setting Function

1 ON Select RS-232 Input Port

1 OFF Select RS-485 Input Port
3 & 4 ON Enable RS-485 Terminator for TXD+/­3 & 4 OFF Disable RS-485 Terminator for TXD+/­5 & 6 ON Enable RS-485 Terminator for RTS+/­5 & 6 OFF Disable RS-485 Terminator for RTS+/­7 & 8 ON Enable RS-485 Terminator for RXD+/­7 & 8 OFF Disable RS-485 Terminator for RXD+/-

Table 7- Switch S2 Configuration Settings

Position Setting Function

1, 3 & 5 ON Select RS-232 Input Port
1, 3 & 5 OFF Select RS-485 Input Port
2, 4 & 6 ON Select RS-485 Input Port
2, 4 & 6 OFF Select RS-232 Input Port

7 ON 4-Wire Network
7 OFF 2-Wire Network
8 ON 2-Wire Network
8 OFF 4-Wire Network

Indicators

There are Two LEDs on the Isolated RS-485 Interface Board. LED DS1 will be illuminated
when data is being transmitted and LED DS2 will be illuminated when data is being
received.

WIRING

RS-232 Interface Between Isolated RS-485 Intf. Board and the Host Node

When it is desired to establish an RS-232 Interface between the Isolated RS-485 Interface
Board and the Host DPC/RTU, transmitter or computer a 24-gauge conductor cable, such as

PIP-ISORS485 Page 5 Isolated RS-485 Interface Board

Belden 9535 should be used. It should be noted that the Isolated RS-485 Interface Board
provides 15KV surge protection per IEC-801 on all signals associated with this interface.

RS-485 Interface Between Isolated RS-485 Intf. Board and the Host Node

When it is desired to establish an RS-485 Interface between the Isolated RS-485 Interface
Board and the Host DPC/RTU or transmitter a low capacitance 24-gauge 3-twisted pair
communications grade cable, such as Belden 9843 should be used. It should be noted that
the Isolated RS-485 Interface Board provides 15KV surge protection per IEC-801 on all sig­nals associated with this interface.

Isolated RS-485 Port Interface to LAN

Two-wire or four-wire RS-485 networks are supported. For two-wire applications, a low
capacitance 24-gauge communications grade 2-twisted pair cable, such as Belden 9842,
should be used. The cable shield should be connected to the Chassis Ground terminal, i.e.,
TB2 Pin 6 (at one end only). For four-wire applications a similar 3-twisted pair cable, such
as Belden 9843, should be used. Again, the cable shield should be connected to the Chassis
Ground terminal (at one end only). It should be noted that the Isolated RS-485 Interface
Board provides 15KV surge protection on all signals associated with this interface.

Figure 3 - 2-Wire RS-485 LAN using Isolated RS-485 Interface Boards

Note: Jumpers W5 & W6 aren’t required at the most distant Slave Node
unless the LAN is operating at other than 1Mbaud; however, they aren’t
detrimental if they are installed.

Figure 4 - 4-Wire RS-485 LAN using Isolated RS-485 Interface Boards

Field Terminations for RS-485

The maximum number of nodes that can be connected to a RS-485 network is 32 including
the master. For maximum protection against unwanted interference, noise and spurious

PIP-ISORS485 Page 6 Isolated RS-485 Interface Board

emission, the shield of each LAN segment should be terminated to the Chassis Ground at
one end only. This practice will eliminate the formation of ground loops, thereby
minimizing ground induced noise currents in the LAN. A Chassis Ground connection is
provided on each Isolated RS-485 Interface Board at TB2 - Pin 6. In addition, the chassis of
each Isolated RS-485 Interface Board should be connected to the nearest earth ground via a
short length of 12-gauge stranded copper wire in order to take advantage of the built-in
surge protection capability. The Isolated Ground terminal (TB2-5) of all nodes on the two­wire RS-485 LAN must be connected via a third wire (within the second twisted pair).

For four-wire LANs 3-twisted pairs of wires are required. Shielding is not required (but is
recommended). The maximum network length for the available asynchronous speeds (up to

38.4 KBaud) is 4000 feet (point to point) 1000 feet (for multiple nodes). For LANs utilizing
synchronous speeds up to 187.5 KBaud (for two-wire LANs) or up to 1 MBaud (for four-wire
LANs) the maximum network length is 1000 feet (300 meters) or 200 feet (60 meters)
respectively. The Isolated Ground terminal (TB2-5) of all nodes on the four-wire RS-485
LAN must be connected via a fifth wire (within the third twisted pair).

Figure 5 - Typical 2-Wire Asynchronous RS-485 LAN

Figure 6 - Typical 2-Wire Synchronous 187.5KBaud RS-485 LAN

Figure 7 - Typical 4-Wire Synchronous 1MBaud RS-485 LAN

PIP-ISORS485 Page 7 Isolated RS-485 Interface Board

Figure 8 - Isolated RS-485 LAN - Typical Installation

PIP-ISORS485 Page 8 Isolated RS-485 Interface Board

ISOLATED RS-485 INTERFACE BOARD SPECIFICATIONS

Performance Specifications

Baud Rate (Max.): 38.4K Asynchronous (2-wire or 4-wire)

187.5K Synchronous (2-wire), 1M Synchronous (4-wire)

Multidrop (Max.): 32 Nodes

Network Termination: 100 Ohm Resistors for TX and RX Circuits on End Nodes

Topology: Master/Slave: (TXD+ to RXD+) & (TXD- to RXD-)

Isolation: Optically Isolated Data Signals

Common Mode Range: -7 Volts to +12 Volts (DC) (With respect to Isolated Ground)

Surge Protection: Meets IEC-801 (To Isolated Ground)

Isolated Ground Terminal Provided for Local Connection to Cable Shield

(one end of shield only)

Surge Path: Terminal Provided for Local Connection from Isolated Chassis

Ground to Earth Ground through a 280V Sealed Surge
Absorber

Input Voltage: +9 to +35 VDC

Input Power: (4-Wire) 65 mA @ 24 VDC (1.56 watt)

(2-Wire) 40 mA @ 24 VDC (1 watt)

Environmental Specifications

Operating Temperature: -40° to +70° (C) [-40° to +158° (F)]

Storage Temperature: -40° to +85° (C) [-40° to +185° (F)]

Humidity: 5% to 95% (Non-condensing)

RFI Susceptibility: Per SAMA Standard PMC 33.1-1978, Using Field of 10V/Meter

(From 20 MHz to 500 MHz)

Vibration: 10-150 Hz, 1g

150-2000 Hz, 0.5g

Part Numbers

Two-wire Isolated RS-485 Interface Board: With DIN Base: 392909-01-4
Without DIN Base: 392909-02-2
Four-wire Isolated RS-485 Interface Board: With DIN Base: 392909-03-0
Without DIN Base: 392909-04-9

PIP-ISORS485 Page 9 Isolated RS-485 Interface Board

Isolated RS-485 Interface Board

Special Instructions for Class I, Division 2 Hazardous Locations

1. The Bristol, Inc. Isolated RS-485 Interface Board is listed by Underwriters Laboratories

(UL) as nonincendive and is suitable for use in Class I, Division 2, Groups A, B, C and D
hazardous locations and non-hazardous locations only. Read this document carefully
before installing a nonincendive Bristol Isolated RS-485 Interface Board. In the event of
a conflict between the Isolated RS-485 Interface Board User Manual (PIP-ISORS485)
and this document, always follow the instructions in this document.

2. All power and I/O wiring must be performed in accordance with Class I, Division 2

wiring methods as defined in Article 501-4 (b) of the National Electrical Code, NFPA 70
for installations within the United States, or as specified in Section 18-152 of the
Canadian Electrical Code for installation in Canada.

3. WARNING: EXPLOSION HAZARD - Substitution of components may impair

suitability for use in Class I, Division 2 environments.

4. WARNING: EXPLOSION HAZARD - When situated in a hazardous location,

turnoff power before servicing/replacing the unit and before installing or
removing I/O wiring.

5. WARNING: EXPLOSION HAZARD - Do Not disconnect equipment unless the

power has been switched off or the area is known to be nonhazardous.

03/14/2007 Appendix A, Document PIP-ISORS485 Page 1 of 1

Product Information Package

PIP-ISORS485

Isolated RS-485 Interface Board - 33XX, 3508, 3530 & 3808

Mar., 2007

Emerson Process Management
Bristol, Inc.

1100 Buckingham Street
Watertown, CT 06795
Phone: [phone]
Fax: [phone]
www.EmersonProcess.com/Bristol

Emerson Electric Canada, Ltd.
Bristol Canada

6338 Viscount Rd.
Mississauga, Ont. L4V 1H3
Canada
Phone: [phone]
Fax: [phone]
www.EmersonProcess.com/Bristol

Emerson Process Management
BBI, S.A. de C.V.

Homero No. 1343, 3er Piso
Col. Morales Polanco
11540 Mexico, D.F.
Mexico
Phone: [phone]
Fax: [phone]
www.EmersonProcess.com/Bristol

Emerson Process Management
Bristol Babcock, Ltd.

Blackpole Road
Worcester, WR3 8YB
United Kingdom
Phone: [phone]
Fax: [phone]

www.EmersonProcess.com/Bristol
Emerson Process Management

Bristol, Inc.

22 Portofino Crescent,
Grand Canals Bunbury, Western Australia 6230
Mail to: PO Box 1987 (zip 6231)
Phone: [phone]
Fax: [phone]
www.EmersonProcess.com/Bristol

The information in this document is subject to change without notice. Every effort has
been made to supply complete and accurate information. However, Bristol, Inc.
assumes no responsibility for any errors that may appear in this document.

If you have comments or questions regarding this manual, please direct them to your
local Bristol sales representative, or direct them to one of the addresses listed at left.

Bristol, Inc. does not guarantee the accuracy, sufficiency or suitability of the software
delivered herewith. The Customer shall inspect and test such software and other
materials to his/her satisfaction before using them with important data.

There are no warranties, expressed or implied, including those of merchantability and
fitness for a particular purpose, concerning the software and other materials delivered
herewith.

TeleFlow™ is a trademark of Bristol, Inc. The Emerson logo is a trade mark and service
mark of Emerson Electric Co. Other trademarks or copyrighted products mentioned in
this document are for information only, and belong to their respective companies, or
trademark holders.

Copyright (c) 2007, Bristol, Inc., 1100 Buckingham St., Watertown, CT 06795. No part
of this manual may be reproduced in any form without the express written permission of
Bristol, Inc.

Return to CI-3305 Table of Contents

Return to CI-3310 Table of Contents

Return to CI-3330 Table of Contents

Return to CI-3335 Table of Contents

Return to CI-3508-10C Table of Contents

Return to CI-3508-30C Table of Contents

Return to CI-3530-10B Table of Contents

Return to CI-3530-15B Table of Contents

Return to CI-3530-20B Table of Contents

Return to CI-3530-25B Table of Contents

Return to CI-3530-35B Table of Contents

Retrun to CI-3530-45B Table of Contents

Return to CI-3530-50B Table of Contents

Return to CI-3808 Table of Contents

Return to PIP Table of Contents

Return to the List of Manuals