Control Technology Inc. 2500 Series Operating instructions

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
Copyright © 2014 Control Technology Inc.
All rights reserved.
This manual is published by Control Technology Inc., 5734 Middlebrook Pike, Knoxville, TN 37921.
This manual contains references to brand and product names which are trade names, trademarks,
and/or registered trademarks of Control Technology Inc. Siemens® and SIMATIC® are registered
trademarks of Siemens AG. Other references to brand and product names are trade names,
trademarks, and/or registered trademarks of their respective holders.
DOCUMENT DISCLAIMER STATEMENT
Every effort has been made to ensure the accuracy of this document; however, errors do
responsibility for direct or consequential damages resulting from the use of this document. This
document is provided without express or implied warranty of any kind, including but not limited
to the warranties of merchantability or fitness for a particular purpose. This document and the
products it references are subject to change without notice. If you have a comment or discover
an error, please call us toll-free at 1-800-537-8398 or email us at [e-mail].
REVISION HISTORY
V1.0 05/28/14 Original Issue
V1.1 7/29/21 Added note about NOT crossin
g
+ to in Section 2.8

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
This Installation and Operation Guide provides reference information for the CTI 2500C-RBC-
RS485 RS485 Remote Base Controller. The information in this manual is directed to individuals who
will be installing the module and configuring it for use with a CTI 2500 Series® or Simatic® 505
Processor.
We assume you are familiar with the installation and operation of:
2500 Series® programmable controllers
IO Netwroking
PLC Programming Software

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
NOTE:
Notes alert the user to special features or procedures.
CAUTION:
Cautions alert the user to procedures that could damage equipment.
WARNING:
Warnings alert the user to procedures that could damage equipment and endanger the user.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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CHAPTER 1. DESCRIPTION..................................................................................5
1.1 Introduction.....................................................................................................5
1.2 Communication Ports.....................................................................................5
1.2.1 Serial Port 6
1.2.2 I/O Port 6
CHAPTER 2. INSTALLATION................................................................................7
2.1 Installation Planning .......................................................................................7
2.1.1 Choosing Remote I/O Media 7
2.1.2 Selecting a Remote Base Address 7
2.1.3 Setting Module Hardware Options 7
2.1.4 Connecting to Remote I/O Cable 7
2.2 Unpacking the Module ...................................................................................7
2.3 2500-RBC-RS485 Module Board Layout......................................................8
2.4 2500C-RBC-RS485 Front Panel Layout .......................................................9
2.5 Configuring the Module............................................................................... 10
2.5.1 Setting the RS232 Port Baud Rate 10
2.5.2 Setting the Output State on Communication Loss 11
2.5.3 Setting the Remote Controller Base Station Address 12
2.6 Physical Installation..................................................................................... 12
2.7 Connecting to the RS232 Port.................................................................... 13
2.8 Connecting the Remote I/O Cable ............................................................. 13
2.9 Operation of LED Display ........................................................................... 14
2.10 System Status Words ................................................................................. 15
Appendix A. REMOTE I/O INSTALLATION GUIDELINES ................................................. 16
A. 1. Cable Layout Planning................................................................................ 16
A. 2. Cable Selection ........................................................................................... 16
A. 3. Cable Lengths ............................................................................................. 17
A. 4. Bus termination ........................................................................................... 19
A. 5. Cable Routing and Layout Guidelines........................................................ 20
A. 6. Laying Cables Outside of Control Cabinets ............................................... 20
Appendix B. .................................................................... 21
Appendix C. SPECIFICATIONS ........................................................................................... 22
General 22
Ports 22
Environmental ........................................................................................................... 22
Appendix D. LIMITED PRODUCT WARRANTY.................................................................. 23

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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Figure 1. 2500C-RBC-RS485 Front Panel.............................................................................5
Figure 2. 2500C-RBC-RS485 2500C-RBC-RS485 Module Board Layout .............................8
Figure 3. 2500C-RBC-RS485 Front Panel.............................................................................9
Figure 4. 2500C-RBC-RS485 Front Panel...........................................................................10
Figure 5. 2500C-RBC-RS485 Freeze Jumper Selection Jumper .........................................11
Figure 6. 2500C-RBC-RS485 Serial Port Pin outs...............................................................13
Figure 7. 2500C-RBC-RS485 Serial Port Pin outs...............................................................13
Figure 8. Remote I/O Installation .........................................................................................16
Figure 9. Trunk Length Measurement..................................................................................19
Figure 10. T-Connection Trunk Length ................................................................................19

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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1.1 Introduction
The CTI 2500C-RBC-RS485 RS485 Remote Base
Controller is a member of Control Technology's family
of I/O modules compatible with programmable
controllers from Siemens® and CTI.
The 2500C-RBC-RS485 RS485 Remote Base Controller
(RBC) allows a 2500 Series® Compact I/O base to
function as a remote base. It provides the following
functions:
Compatible with CTI 2500 Series® and
Simatic® 505® CPUs.
Can be used in currently-available CTI 2500
Series® Compact 4, 8, and 16-slot bases
Supports communication speeds 1Mbits/sec and
maximum cable distance of 1000 meters
LED display which shows error and status codes
Front panel thumbwheel switch for setting the
station address
On-board RS232 port which can be used for
PLC programming and configuration.
The 2500C-RBC-RS485 resides in 2500 Series®
Compact base. It installs in the second slot from the left,
adjacent to the power supply module.
Do not install this module into a normal I/O slot, as
damage can occur.
1.2 Communication Ports
The 2500C-RBC-RS485 RS485 RBC has two communication ports on the front panel.
Figure 1. 2500C-RBC-RS485 Front
Panel

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
6
1.2.1 Serial Port
The RS232 port is provided to interface to PLC programming and configuration tools such as
TISOFTTM. A standard 9-pin PC-compatible RS232 serial cable is used to connect to the
programming device or modem. The port pinout is provided in Section 2.6 of this manual.
1.2.2 I/O Port
The I/O Port connects the 2500C-RBC-RS485 to a SIMATIC® 505 compatible RS485
Remote I/O channel. This enables the remote CPU to control the I/O modules in the
base where the RBC is located.
The Remote I/O Port interface is a 9-pin D-Shell connector as detailed in Section 2.7 of
this manual. Recommended guidelines for planning, selection, and installation of
Remote I/O system is included in Appendix A.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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The installation of the Model 2500C-RBC-RS485 RS485 Remote Base Controller consists of
the following steps:
1) Planning the installation
2) Verifying power requirements
3) Unpacking and configuring the module
4) Physical installation
5) Connecting cables
6) Checking the module operation
2.1 Installation Planning
2.1.1 Choosing Remote I/O Media
The 2500C-RBC-RS485 attaches directly to the RS485 Remote I/O cable using a DB9
connector. We recommend using cable designed specifically for RS485 systems, such as
Belden 3105A. See Appendix A for information related to cable specifications, layout, and
installation.
2.1.2 Selecting a Remote Base Address
Before proceeding, you must determine what address you will assign to the RBC. Remote Base
addresses range from 1 to 15. In CTI 2500 Series® and Simatic® 505® systems, address 0 is
reserved for the local base where the CPU is installed. Note that each Remote Base on the
Remote I/O channel must have a unique address
2.1.3 Setting Module Hardware Options
The RBC includes a hardware setting for selecting the state of the base discrete outputs in the
event of a loss of communication with the CPU. The module can be configured to set all
outputs off, or to leave outputs at their last states.
2.1.4 Connecting to Remote I/O Cable
The Remote I/O connector should be wired as shown in Section 2.7.
2.2 Unpacking the Module
Open the shipping carton and remove the special anti-static bag that contains the module.
After discharging any static build-up, remove the module from the static bag. Do not discard
the static bag. Always use this bag for protection against static damage when the module is not
inserted into the I/O base.
CAUTION:
The components on the 2500C-RBC-RS485 module printed circuit card can be damaged by static
electricity discharge. To prevent this damage, the module is shipped in a special anti-static bag.
Static control precautions should be followed when removing the module from the bag and when
handling the printed circuit card during configuration.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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2.3 2500-RBC-RS485 Module Board Layout
Figure 2. 2500C-RBC-RS485 2500C-RBC-RS485 Module Board Layout
Module Front Panel
Serial Port Baud Rate
Selection Switches
Back
p
lane Connector
Freeze Jum
p
er JP4

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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2.4 2500C-RBC-RS485 Front Panel Layout
Figure 3. 2500C-RBC-RS485 Front Panel
Status Indicator
RBC Address Selection
Thumbwheel Switch
Serial RS-232 9
p
in Port
Remote RS-485 9
p
in Port

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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0
2.5 Configuring the Module
There are three steps to configuring the module and making it fully operational:
1. Setting the RS232 Port baud rate
2. Setting the Remote Base Controller address
3. Setting the output state on communication loss (Freeze Jumper)
Figure 2. 2500C-RBC-RS485 2500C-RBC-RS485 Module Board Layout indicates the location
of the RS232 port baud rate selection switches, the RBC station address thumbwheel, and
Freeze Jumper. The remainder of this section describes the function of the individual settings.
2.5.1 Setting the RS232 Port Baud Rate
Switches SW1-SW4 are used for setting the baud rate of the RS-232 serial port. The supported
baud rates are shown in the following table. All other switch combinations are invalid.
Figure 4. 2500C-RBC-RS485 Front Panel
Baud Rate SW1 SW2 SW3 SW4
19200 1 1 0 1
9600 1 1 1 1
2400 0 1 1 1
1200 1 0 1 1
300 0 0 1 1
Serial Port Selection
Switches Note: The
picture shows the
Baud Rate set at 9600.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1 11
2.5.2 Setting the Output State on Communication Loss
When I/O channel communication to a remote base is lost, the state of the discrete outputs is determined
by the selection made on the 2500C-RBC-RS485 jumper JP4 (Off/Freeze). Figure 5. 2500C-RBC-
RS485 Freeze Jumper Selection Jumper shows the location of the jumper on the 2500C-RBC-RS485.
NOTE:
The 2500C-RBC-RS485 ships with the FREEZE jumper in the OFF setting.
If the jumper JP4 is missing from the board, the 2500C-RBC-RS485 defaults to the OFF
setting.
For discrete output modules, the state of the outputs is determined solely by the position of the
Off/Freeze jumper JP4 on the 2500C-RBC-RS485.
For analog/word output modules, the state of the outputs is influenced not only by the position of the
option. See the table below.
RBC Off/Freeze
Selection
Analog/Word Module
Zero/Hold Selection Analog/Word Output State
Off Zero Zero*
Off Hold Last Value Last Value
Off No selection Last Value
Freeze Zero Last Value
Freeze Hold Last Value Last Value
Freeze No selection Last Value
*see the user manual of
y
our analo
g
/word out
p
ut module for details
Notice that the FREEZE option on the RBC overrides the Zero selection on the analog/word output
module; likewise, when Hold Last Value is selected on the analog/word output module, that selection
overrides the OFF option on the RBC jumper.
WARNING:
If the RBC fails or loses power during system operation, all outputs will turn OFF(0)
regardless of the Freeze Jumper setting. This could result in damage to equipment
and/or serious injury to personnel.
Figure 5. 2500C-RBC-RS485 Freeze Jumper Selection Jumper
JP4 Freeze Jumper
Shipped in the OFF
position on PINS 1 & 2
(Note Shown in the ON
Position
)
This diagram shows other jumpers
in place. When shipped these
jumpers are not usually populated.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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2
2.5.3 Setting the Remote Controller Base Station Address
A thumbwheel switch is provided to set the base address to the 2500C-RBC-RS485 for Remote
I/O station identification. A maximum of 15 remote bases can be connected to the CTI 2500
Series® CPU or Siemens® 545/555/575 CPU.
NOTE:
When connecting the 2500C-RBC-RS485 to a CTI 2500 Series® CPU or Siemens®
545/555/575 CPU, only addresses between 1 and 15 are valid. Each installed 2500C-RBC-
RS485 must have a unique station number.
Care should be taken to prevent circumstances which cause the CPU to lose communication
with the 2500C-RBC-RS485 while the system is operating. Loss of communication between
the CPU and RBC will cause the base to be logged off from the CPU. This can cause
intermittent process operation.
WARNING:
The following events will cause loss of communication with the 2500C-RBC-RS485 and
result in the base being logged off from the CPU.
.
2) Changing the thumbwheel switch station address while the system is operating.
These events could cause unpredictable process operation and result in damage to
equipment and/or serious injury to personnel.
When a base if logged off, the CPU zeroes all image register input points associated with the
base and all outputs go to the value determined by the installed output module. Discrete outputs
turn OFF (0) and Analog/Word outputs are set according to the Zero/Hold Last Value settings
in each particular module. Your program can monitor the CPU Status Words to detect this
condition and control the outputs from other remote bases as appropriate for the application.
Details on the Status Words and programming examples can be found in the SIMATIC®
545/555/575 Programming Reference User Manual .
2.6 Physical Installation
To insert the module into the I/O base, hold the top and bottom of the bezel and slide the
module carefully into the slot, pushing it all the way into the base. If you have inserted the
module correctly, you will feel a slight increase in resistance as the module mates with the base
backplane connector. Once the module is fully seated in the slot, tighten the captive screws at
the top and bottom to hold the module in place. To remove the module from the I/O base,
loosen the captive screws, and then pull the module from the base. Take care not to damage the
connector at the back of the module when inserting or removing the module.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1 1
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2.7 Connecting to the RS232 Port
The RS232 port is provided to interface to PLC programming and configuration tools such as
TISOFTTM. The use of this port is optional. A standard 9-pin PC RS232 serial cable can be used
to connect to the programming device or modem. The port details are shown in Figure 3.
5
9
6
1
9-Pin D-Shell Male Connector
Compatible with standard PC Serial Port
SGND (5)
RxD (2)
TxD (3)
DCD (1)
DTR (4)
DSR (6)
RTS (7)
CTS (8)
Figure 6. 2500C-RBC-RS485 Serial Port Pin outs
2.8 Connecting the Remote I/O Cable
The I/O Port connects the 2500C-RBC-RS485 to a SIMATIC® 505 compatible RS485
Remote I/O channel. This enables the remote CTI 2500 Series® or Simatic® 505® CPU
to control the I/O modules in the base where the RBC is located.
The Remote I/O Port interface is a 9-pin D-Shell connector with pinout as shown in
Figure 3. Recommending wiring for the Remote I/O cabling is detailed in Siemens®
545/555/575 System Manual. Figure 4 shows the pinout for the I/O Port.
IMPORTANT NOTE: When wiring the remote I/O cable, do not cross over the TX/RX- and
TX/RX+. Always wire + to + and to -.
5
9
6
1
TX/RX- (8) TX/RX+ (3)
GND (5)
9-Pin D-Shell Female Connector
Figure 7. 2500C-RBC-RS485 Serial Port Pin outs

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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2.9 Operation of LED Display
The LED Display is used to indicate the status of the 2500C-RBC-RS485 Remote Base
Controller as shown in the following table:
Display Definition Communications
to RBC
Comment / Action
0 Module Ready OK Fully Operational and online with CPU.
1 Diagnostics Failure None Serious malfunction. Place system in safe
state and contact CTI Technical Support.
2 Module Mismatch OK I/O modules installed do not match the
expected configuration in the CPU.
3 I/O Communications
timeout
Failed There is no communication with the CPU.
Place the system in a safe state. Check
power, cabling, and connection to the CPU.
4 Ram Parity Error Failed Serious malfunction. Place system in safe
state and contact CTI Technical Support.
5Standby, No
Configuration
None Not used.
6 Address Mismatch OK Not used.
7 Communications
OK, No
Configuration
OK 2500C-RBC-RS485 is not configured.
Configure RBC in CPU.
8 Watchdog timeout Failed Serious malfunction. Place system in safe
state and contact CTI Technical Support.
*blank* No Code Displayed None Serious condition. 2500C-RBC-RS485 is not
operational. If power to base is OK, contact
CTI Technical Support.
C Not Used Not Used.
A,B,E Internal Failure Failed Hardware failure detected during power on
initialization tests.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1 1
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2.10 System Status Words
There are a number of system status words which are important in observing remote I/O system
operation and isolating problems. If you are experiencing remote I/O problems, you should pay
careful attention to the following status words.
STW2 Base controller status
STW11-26 I/O module status
STW145 Remote I/O receive errors
STW146 Remote I/O timeout errors
STW168 Dual RBC Status(not Used.Future)
STW184 I/O module mismatch
STW210 Remote I/O base poll enable flags
STW455-461 Remote base receive errors
STW471-485 Remote base abnormal logoff counts
STW487-501 Remote base timeout counts
More complete information and a list of the 2500 Series® Processor System Status Words can
be found in the 2500 Series® Processor Installation and Operation Guide:
http://www.controltechnology.com/Files/Products/2500-(Classic)/2500-Cxxx/manuals/CTI-
2500-IOG-(62-370)

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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Appendix A. REMOTE I/O INSTALLATION GUIDELINES
These Remote I/O Installation Guidelines are based on standard RS485 wiring practices.
The Remote I/O cable system consists of a main trunk line and drop lines which connect the
CPU/Local Base and Remote Base(s) to the trunk line by means of terminal blocks as shown in
Figure 8. Remote I/O Installation.
Local Base
T TT
Remote Base Remote Base
Trunk Lines
Drop Lines
Drop Line
T = Terminal Block
Figure 8. Remote I/O Installation
A. 1. Cable Layout Planning
Use the following guidelines for planning the Remote I/O cable routing and locations:
The ideal cable installation is a single, unbranched trunk line with short drop lines and
termination resistor at each end
Maximum length of a drop line should not exceed 33 feet (10 m)
Drop lines less than 3.3 feet (1 m) do not count toward cable length calculations
The total length of all drop lines should be much less than the length of the trunk line
-
drop line.
A. 2. Cable Selection
Data transfer in the Remote I/O systems is based on a symmetrical RS485 bus system using
shielded twisted pair cable. The cable shield is used to improve the immunity to
electromagnetic interference.
The ideal cable provides low signal attenuation for long trunk lines and flexibility for ease of
installation. The recommended cable should include the characteristics as shown in the
following table.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1 1
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CTI recommends Belden 3105A cable for wiring remote I/O. The following table contains the
general recommended cable specs for RS485 remote I/O wiring and the preferred Beldon cable
type specifications.
Cable Characteristic Recommended Belden® 3105A
Conductors 18AWG to 22AWG uniform
twisted-
p
air
2-conductors,22AWG,.030
in
(
7.5mm
)
, 7x30 stranded
Shielding 100% shield coverage 100% coverage with 90%
co
p
p
er braid
p
lus drain wire
Characteristic
Impedance
100 to 150
Capacitance < 50 pF/m 11 pF/ft (36 pF/m)
DC Resistance Resistance of installed length
< characteristic impedance
Attenuation < 1.0 dB/100 ft
(
1.0 dB/ 30 m
)
0.5 dB/100 ft (0.5 db/30 m)
@
1MHz
Velocity of
Pro
p
a
g
ation
> 65% 78%
O
p
eratin
g
Tem
p
erature 0 to +60 ºC -20 to +60 ºC
Alternatively, Beldon 9860, 9271, and 9182 cable can be used to wire your remote I/O. The
table below gives the cable specifications for these models.
Alternative Cable S
p
ecs
Belden
Cable T
y
p
e
Outside
Diameter Im
p
edance Ca
p
acitance Velocit
y
Center
Conductor
9182 0.35 in.
8.9 mm
150 ohm 28.9 pf/m 0.78c 22 AWG 19x34
46 ohm/km
9271 0.24 in
6.1 mm
124 ohms 40 pf/m 0.66c 25 AWG 7x33
104.3 ohm/km
9860 0.44 in.
11.2.mm
124 ohms 35.8 pf/m 0.78c 16 AWG Solid
13.8.ohm/km
A. 3. Cable Lengths
Maximum permissible cable length is dependent on cable characteristics and number of
terminal blocks used in the installation. Terminal blocks are used to connect drop lines and/or
extend Remote I/O cable trunk line. The following table contains the maximum recommended
cable length (Trunk Length + Drop Lines) for Belden® 3105A cable. It is possible to have
longer cable runs if larger diameter wire is used.

CTI 2500C-RBC-RS485 Installation and Operation Guide V1.1
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8
Number of Installed
Drop Lines
Maximum Cable Length in
Feet
(
Meters
)
Belden 3105A
2-5 2200 (670)
6 2133 (650)
7 2067 (630)
8 2000 (610)
9 1933 (589)
10 1867 (569)
11 1800 (548)
12 1733
(
528
)
13 1667
(
508
)
14 1600
(
488
)
15 1533
(
467
)
16 1467
(
447
)
17 1400 (427)
Number of
Drop Lines
Maximum Distance
Belden 9182 Belden 9271 Belden 9860
2 - 5 2200 ft
(
670 m
)
1100 ft
(
335 m
)
3300 ft
(
1006 m
)
6 2133 ft
(
650 m
)
1067 ft
(
325 m
)
3200 ft
(
975 m
)
7 2067 ft
(
630 m
)
1033 ft
(
315 m
)
3100 ft
(
945 m
)
8 2000 ft
(
610 m
)
1000 ft
(
305 m
)
3000 ft
(
914 m
)
9 1933 ft
(
589 m
)
967 ft
(
295 m
)
2900 ft
(
884 m
)
10 1827 ft
(
569 m
)
933 ft
(
284 m
)
2800 ft
(
853 m
)
11 1800 ft
(
548 m
)
900 ft
(
274 m
)
2700 ft
(
823 m
)
12 1733 ft
(
528 m
)
867 ft
(
264 m
)
2600 ft
(
792 m
)
13 1677 ft
(
508 m
)
833 ft
(
254 m
)
2500 ft
(
762 m
)
14 1600 ft
(
488 m
)
800 ft
(
244 m
)
2400 ft
(
732 m
)
15 1533 ft
(
476 m
)
767 ft
(
234 m
)
2300 ft
(
701 m
)
16 1400 ft
(
427 m
)
733 ft
(
223 m
)
2200 ft
(
671 m
)