Description

GE IC697BEM721

The GE IC697BEM721 is a processor module for the VersaMax series of Programmable Logic Controllers (PLCs). As the "computational and control core" of the PLC system, it mainly undertakes key tasks such as user program execution, I/O module management, data processing, communication coordination, and system diagnosis.

Its core function is to run control programs written in IEC 61131-3 standard programming languages (such as ladder logic and structured text) to collect real-time on-site signals (e.g., sensor data, switch status) from various I/O modules. After logical and arithmetic operations, it outputs control commands to drive the actions of actuators (e.g., valves, motors). Meanwhile, it has capabilities including multi-protocol communication, program storage and backup, and online debugging, making it suitable for the complex needs of small and medium-sized industrial automation control systems.

With balanced computing performance, flexible expandability, reliable industrial-grade design, and high cost-effectiveness, this module is widely used in production line control, equipment linkage, and process monitoring scenarios in fields such as food and beverage packaging, building materials production, warehousing and logistics, and small chemical equipment. It is a core component for building small and medium-sized high-reliability automation systems.

1. Technical Parameters

1.1 Computing Performance Parameters

• Adopts a 32-bit RISC processor with a core computing frequency of 400MHz.
• Ladder logic execution speed: 0.1μs per instruction; structured text execution speed: 0.06μs per instruction. It supports a cyclic scan cycle of ≤2ms for 50,000-step programs.
• Supports multi-task scheduling, with 8 task priorities configurable (4 of which are real-time tasks). Task switching time is ≤15μs, meeting the parallel processing needs of real-time control and non-real-time monitoring in small and medium-sized production lines.

1.2 Storage Capacity Parameters

• Built-in 8MB non-volatile user program memory (Flash), supporting permanent program storage without the need for a backup battery when power is off.
• 16MB data memory (RAM), of which 8MB can be configured as a power-off retention area (backed by a super capacitor with a backup time of ≥48 hours).
• Supports a maximum external SD card expansion of 32MB for program backup, data log storage, and firmware updates.
• Built-in 512KB high-speed cache (Cache) to improve program execution and data access efficiency.

1.3 Expansion and I/O Management Parameters

• Supports expansion via VersaMax series racks, with up to 4 expansion racks connectable, and each rack can be configured with 16 I/O modules.
• Maximum supported I/O points: 4096 digital points, 512 analog points.
• Supports hot-swappable I/O modules; some I/O modules can be replaced while the system is running without affecting the operation of the main program.
• Built-in I/O scanner, supporting batch collection and distribution of I/O data with a scanning rate of ≥800 points per second. It also supports I/O data deadband configuration to reduce invalid data transmission.

1.4 Communication and Environmental Parameters

• Integrates 2 100Mbps Ethernet ports (supporting Modbus/TCP and EtherNet/IP protocols), 1 RS-485 serial port (supporting Modbus-RTU protocol), and supports redundant configuration of Ethernet ports.
• Operating temperature: 0℃~60℃; storage temperature: -40℃~85℃.
• Relative humidity: 5%~95% (no condensation).
• Vibration resistance rating: IEC 60068-2-6 (10Hz~500Hz, acceleration 5g).
• Shock resistance rating: IEC 60068-2-27 (peak acceleration 15g, duration 11ms).
• Protection rating: IP20 (rack-mounted), suitable for installation inside control cabinets.
• Dimensions: 120mm×150mm×55mm, installed using the VersaMax standard rack for easy installation.

2. Functional Features

2.1 Balanced Computing Efficiency for Small and Medium-Sized Control

The 400MHz high-frequency processor, combined with an optimized instruction set, ensures the fast execution of complex control programs for small and medium-sized systems. Even in scenarios with thousands of I/O points connected and multi-loop PID control running, it can still maintain a stable scan cycle. It supports complex operations such as floating-point arithmetic and trigonometric functions with an accuracy of ±1×10⁻⁶, meeting the high-precision requirements of scenarios such as temperature regulation in building materials production and quantitative control in food packaging. The multi-task scheduling function can assign control logic, data processing, and communication interaction to tasks of different priorities, preventing non-real-time tasks from affecting the control response speed.

2.2 Flexible Expansion Architecture to Reduce System Costs

It adopts a distributed architecture of "main rack + expansion racks". High-speed data interaction (with a transmission rate of 500Mbps) is achieved through the inter-rack bus. According to the on-site distribution of equipment, I/O modules can be installed in nearby expansion racks to reduce the length of signal cables and interference. It is compatible with all types of I/O modules in the VersaMax series (digital, analog, high-speed counters, pulse output modules, etc.). It can adapt to the collection and control needs of different signal types without replacing the processor, greatly improving system expandability, reducing later upgrade costs, and meeting the phased construction needs of small and medium-sized enterprises.

2.3 Dual Redundancy Design to Ensure Reliable Operation

It supports two core redundancy modes: Ethernet communication redundancy and power supply redundancy. The Ethernet ports support simple redundant configuration; in case of a communication link failure, manual switching to the standby link (or automatic switching via software) is available. When used with VersaMax series redundant power modules, it can realize uninterrupted switching of the power supply system, meeting the "low downtime" requirements of small and medium-sized production lines, with the overall system availability reaching over 99.99%. The module uses industrial-grade components and has passed strict high-low temperature, vibration, and shock tests, making it suitable for complex operating environments in workshops.

2.4 Multi-Protocol Communication and Convenient O&M

3. Working Principle

3.1 System Initialization and Configuration Loading

After the module is installed in the main rack, it automatically completes hardware self-test when powered on, including the status detection of the processor, memory, communication ports, and rack bus. Upon passing the self-test, it loads the user program and system configuration parameters (e.g., I/O module model, communication protocol, task priority) from the Flash memory. At the same time, it automatically identifies all I/O modules in the main rack and expansion racks, assigns module addresses, and establishes an I/O image area. After completing initialization, it enters the running state.

3.2 User Program Execution and Task Scheduling

The core processor schedules and executes user programs according to task priorities. High-priority tasks (e.g., real-time control logic, emergency shutdown logic) are executed first, while low-priority tasks (e.g., data log recording, report generation) are executed when high-priority tasks are idle. During program execution, it reads real-time collected on-site data from the I/O image area and performs logical operations such as ladder logic and structured text—for example, calculating valve adjustment quantities via the PID algorithm and determining equipment start-stop conditions through interlock logic. The operation results are stored in the output image area.

3.3 I/O Data Interaction and Control Output

The I/O scanner reads input signals (e.g., sensor digital quantities, analog values) from each I/O module at a set cycle (configurable from 1ms to 100ms), updates them to the input image area for program execution and calling. At the same time, it distributes the operation results in the output image area to the corresponding output modules to drive the actions of actuators (e.g., motor starters, solenoid valves), realizing precise control of the production process. It supports interrupt-triggered I/O interaction: when a key input such as an emergency stop signal is detected, it immediately triggers a high-priority interrupt service routine to quickly respond to control needs.

3.4 Communication Interaction and Status Monitoring

4. Common Faults and Solutions

4.1 Fault 1: Processor Fails to Start, Power Indicator Is Off or Flashing

Possible Causes

• Abnormal voltage of the power supply.
• Failure of the power module.
• Poor contact between the processor module and the rack.
• Hardware failure of the processor.

Solutions

1. Use a multimeter to detect the output voltage of the rack power module and confirm it is within the range of 24V DC ±10%. If abnormal, repair or replace the power module.
2. Power off, reinsert the processor module to ensure tight contact between the module and the rack bus, and clean the rack bus contacts.
3. Replace with a standby processor module. If it can start normally, the original module has a hardware failure and needs to be returned to the factory for repair.
4. Check the wiring of the power line to ensure correct connection of positive and negative poles, with no short circuits or loose connections.

4.2 Fault 2: No Data Collection or Abnormal Output in Some I/O Channels

Possible Causes

• Damaged I/O module channel.
• Loose or poor contact of terminal blocks.
• Damaged signal cables.
• Incorrect channel configuration.

Solutions

1. Use a multimeter to detect the sensor output signal corresponding to the faulty channel and confirm the signal is normal.
2. Check the terminal blocks, re-tighten the wiring, and replace damaged signal cables.
3. Connect the sensor of the faulty channel to a standby channel. If collection is normal, the original channel is damaged, and the I/O module needs to be replaced.
4. Check the channel configuration via programming software to ensure the signal type, range, and other parameters match the actual situation. Reconfigure if there is an error.

4.3 Fault 3: Communication Interrupted with HMI or SCADA System

Possible Causes

• Loose or damaged communication cables.
• Incorrect IP address or protocol configuration.
• Failure of the Ethernet port.
• Failure of the upper-level system’s communication port.

Solutions

1. Reinsert the communication cable, test the cable continuity with a cable tester, and replace with a shielded cable if damaged.
2. Check the IP address, subnet mask, and gateway of the processor and the upper-level system to ensure they are in the same network segment with no conflicts. Test network connectivity using the ping command.
3. Confirm that the communication protocol and parameters of both parties are consistent (e.g., Modbus/TCP port number and slave address).
4. Replace the processor with a standby Ethernet port, reconfigure, and test. If functionality is restored, the original port is faulty.

4.4 Fault 4: Abnormal Program Execution with Control Logic Errors

Possible Causes

• Logical errors in the user program.
• Damaged program storage area.
• Program crash caused by interference.
• Unreasonable task priority configuration.

Solutions

1. Perform syntax checks and logical simulations on the user program using programming software to locate and correct logical errors (e.g., infinite loops, conflicting interlock conditions).
2. After backing up the existing program, re-download the complete program to the processor. If it returns to normal, the program storage area has a temporary fault.
3. Check the grounding of the control cabinet to ensure good grounding of the module, and add electromagnetic shielding measures to reduce on-site interference.
4. Optimize task priority configuration: set real-time control tasks to high priority to prevent low-priority tasks from seizing resources.