CTI 2500 Series® Programmable Controllers

FEATURES

• Replaces all Simatic®

545 and 555 models

• Built-in Ethernet and USB ports for 

programming

• Built-in SD Flash card for firmware update 

from flash

• Built-in Profibus and RS485 Remote I/O on 

C200, C300, and C400 models

• Up to 3Mbytes memory, 8192 I/O points, 

512 PID loops & 512 alarms, depending on 

model

• Programmable using Workshop

• Integrity® Real Time Operating System for 

high-reliability and security

SPECIFICATIONS

Ports:

Ethernet, 100Mbit, RJ45

RS232C: DB9 male

Profibus: 12Mbit, DB9 female

Remote I/O: DB9 male

SD Flash card: up to 32G bytes (with Firmware 

V6.18 and higher)

Expansion port: future use

User Memory:

2500-C100: 128K

2500-C200: 256K

2500-C300: 512K

2500-C400: 3072K

Loops / Alarms:

2500-C100: 16 / 32

2500-C200: 64/ 128

2500-C300: 512 / 512

2500-C400: 512 / 512

Status Display: 3-Digit LED display for system

status, error reporting and IP address

Backplane Power: 7 Watts (maximum)

Operating Temperature: 0

o to 60oC

Storage Temperature: -40o

to 85oC

Relative Humidity: 5% to 95%

Agency Approvals: CE, UL UL-C, 

Class 1 Div 2

Shipping Weight: 1.5 lb. (0.68 Kg)

DESCRIPTION

The 2500 Series® Controllers bring exciting new 

features and a new level of process 

performance to Simatic®

505® Control Systems. 

The C100 and C200 models easily handle 

medium to large discrete control applications, as 

well as basic process applications. The C300 

and C400 models are equipped to handle large 

process applications with many PID loops and 

alarms and special mathematical functions. The 

2500 Series® Controllers are designed to 

seamlessly replace all Simatic®

545 and 555 

controllers while providing much higher 

performance at lower cost. The controllers are 

supported by a complete range of digital, 

analog, and specialized I/O modules, power 

supplies, and I/O bases, all available from CTI.

IMPORTANT NOTE: This product includes a lithium battery for backing up the user program, retentive variables, and 

system diagnostics. For safety in transportation, the battery is installed but disabled. Prior to putting this product into 

service, you MUST move dipswitch SW1 to the CLOSED position to enable the battery.

COMPATIBILITY OVERVIEW

The CTI 2500 Series® Processor is designed to be compatible with customer applications that use the Simatic®

545 and 

555 controllers. While the CTI 2500 matches or exceeds the capabilities of these processors in most aspects, there are a 

few areas in which the CTI 2500 operates differently.

Relay Ladder Logic

The RLL used in the controller provides equivalent instructions for all Simatic®

555 instructions except the XSUB 

instruction. External subroutines are not supported. If you download a program containing the XSUB instruction, it will be 

ignored. In many cases XSUB is used for communications with Siemens® Profibus HMI panels. For these installations 

we have a CTI program free on our website which replaces the XSUB. For XSUB uses other than Siemens® HMI panels, 

CTI and our partners can develop XSUB replacement software using SF programming. Please contact us.

Special Function Programs

The controller compiles all SF programs and subroutines. They are compiled in the following situations:

• When a user program is downloaded to the PLC, if the SF Program or subroutine is enabled,

• When the SF program or subroutine is enabled, if the SF program has been modified,

• During a Power Up start (following the application of power).

Programs that contain errors will not be enabled. During a program download, Workshop will display a message 

indicating the error. Once you acknowledge the message, the download will continue, leaving the program disabled. You 

must correct the programming error before the program or subroutine can be enabled. User Programs originally written 

for the Simatic®

505 PLC may contain undetected errors, if the programs were not originally compiled. This can occur 

because the SF interpreter never attempts to execute the instruction due to the branching logic. A common problem is 

that additional ENDIF statements are included or the correct number of ENDIF statements is not present.

Unlike the Simatic®

555, there are no restrictions regarding the instructions that can be used in a compiled program.

User Configuration

The following differences in the user configuration should be noted:

1. Allocation of CS memory is not supported. The CTI 2500 controller uses high speed DRAM to store and execute 

compiled SF programs and subroutines. Consequently, CS memory is not required.

2. User allocation of User Subroutine memory is not supported. The CTI 2500 controller does not support user 

subroutines (XSUB). See XSUB description above.

3. A time slice for Report by Exception (RBE) is not supported. Some alternative solutions exist. Please consult us with 

your exact configuration.

4. A new time slice, Network Communications, has been added to support the local Ethernet port.

I/O Support

The following are not presently supported. This is subject to change.

• Interrupt I/O

Support of Special Function Modules