GE IC695CPU320HU RX3i PACSystems CPU Module

Description

3. Key Technical Specifications

Parameter	Value
Manufacturer	GE Intelligent Platforms / Emerson
Model	IC695CPU320HU
Product Family	PACSystems RX3i
Product Type	PLC CPU Module
Processor	Intel Celeron-M
Processor Speed	1 GHz
User Memory	64 MB Battery-Backed RAM
Flash Memory	64 MB Non-Volatile Flash
Programming Software	Proficy Machine Edition (PME)
Supported Languages	IEC 61131-3
Embedded Communications	RS-232, RS-485
Supported Serial Protocols	SNP, Serial I/O, Modbus RTU Slave
Backplane	RX3i PCI and 90-30 High-Speed Serial Bus
Operating Temperature	0 °C to +60 °C
Typical Power Requirement	+3.3 VDC: 1.0 A; +5 VDC: 1.2 A
Maximum Program Blocks	512 (128 KB per block)

The IC695CPU320 platform uses a 1 GHz processor with 64 MB of battery-backed RAM and 64 MB of Flash memory, supports dual serial ports, and operates on the RX3i dual-backplane architecture.

 

4. Product Introduction

The GE IC695CPU320HU is a high-performance CPU module for the PACSystems RX3i PLC platform. It executes user applications, manages deterministic control tasks, and coordinates communication between local and distributed I/O. It is commonly deployed in manufacturing, water treatment, power generation, and process automation systems.

Compared with earlier RX3i processors, the CPU320 family provides substantially greater processing capacity, expanded user memory, floating-point capability, and support for large control applications while maintaining compatibility with existing RX3i infrastructure when firmware requirements are satisfied. Always verify the installed firmware revision before replacing an existing CPU.

IC695CPU320HU

 

5. Installation & Configuration Guide

 

Stage 1 – Pre-Installation Preparation (10–15 Minutes)

⚠️ Safety First

1. Notify operations personnel of the planned shutdown.
2. Place the controlled process in a safe operating condition.
3. Apply Lockout/Tagout procedures.
4. Remove rack power.
5. Wait at least 5 minutes before handling the CPU.

Tools Required

• Grounded ESD wrist strap
• PH1 screwdriver
• Fluke 115 (or equivalent) digital multimeter
• Wire labels
• Smartphone for documentation
• Laptop with Proficy Machine Edition

Data Backup

Before removing the CPU:

1. Upload the PLC application.
2. Save the hardware configuration.
3. Record IP addresses and communication settings.
4. Document the firmware revision.
5. Photograph all cable connections and rack layout.

 

Stage 2 – Removing the Existing CPU (5–10 Minutes)

1. Disconnect rack power.
2. Remove Ethernet and serial communication cables.
3. Release the CPU retaining latch.
4. Pull the CPU straight out without twisting.
5. Inspect the backplane connector for bent pins, contamination, or heat damage.

⚠️ Do not dispose of the original CPU until the replacement has completed commissioning.

 

Stage 3 – Installing the Replacement CPU (10 Minutes)

1. Wear an ESD wrist strap.
2. Confirm the replacement part number is IC695CPU320HU.
3. Verify the firmware revision is compatible with the existing PLC project.
4. Insert the CPU into the rack guides until fully seated.
5. Lock the retaining mechanism.
6. Reconnect all communication cables.

Installation Checklist

• Correct catalog number verified
• Firmware compatibility confirmed
• CPU fully seated
• Communication cables reconnected
• Rack locking mechanism engaged

 

Stage 4 – Power-On & Functional Testing (15–20 Minutes)

Pre-Power Checks

• Verify 24 VDC supply voltage.
• Check rack grounding.
• Inspect communication cables.
• Confirm there are no shorts on the power rail.

Startup Procedure

1. Energize the RX3i rack.
2. Observe the CPU LEDs.
3. Connect using Proficy Machine Edition.
4. Confirm:
   • CPU status
   • Hardware configuration
   • Firmware revision
   • Communication status
5. Download the backup project if necessary.
6. Verify all critical I/O.

⚠️ Troubleshooting

If the SYS FAULT LED remains illuminated:

• Verify firmware compatibility.
• Compare the installed hardware configuration with the saved project.
• Check for unsupported I/O modules.
• Review diagnostic messages in Proficy Machine Edition.

 

Technical Pitfalls & Survival Guide

❗ Firmware Revision Mismatch

This is one of the most common causes of extended downtime.

I’ve seen technicians replace a failed RX3i CPU with a newer firmware revision, only to spend hours troubleshooting communication errors. The hardware was healthy—the project simply required a different firmware family. Record the firmware version before ordering the replacement.

❗ Configuration Backup

Always upload the PLC application before removing the CPU.

Never assume the latest project stored on a maintenance laptop matches the controller currently running production.

❗ Power Supply Capacity

Adding communication or specialty modules increases rack power consumption.

Calculate the total backplane load and maintain at least a 20% power margin. A fully populated rack can exceed the capacity of an undersized power supply.

❗ Terminal Documentation

Label every communication cable before removal.

It sounds obvious, but I’ve watched experienced technicians reconnect serial cables to the wrong ports after a long shutdown. Five minutes of documentation prevented several hours of troubleshooting.

❗ Electrostatic Discharge (ESD)

Always wear a grounded wrist strap and work on an ESD-safe surface.

I’ve seen a replacement CPU fail immediately after installation because it was handled without proper ESD protection during dry winter conditions. That mistake turned a scheduled maintenance window into an emergency procurement.

Keep these checks in mind and you’ll avoid most of the rework that delays startup.

 

6. Frequently Asked Questions (FAQ)

Q1. Can the IC695CPU320HU be hot-swapped?

No.

The CPU controls the entire RX3i system. Removing it while energized immediately stops controller execution and may corrupt memory. Always perform a controlled shutdown.

Q2. Will replacing the CPU erase my PLC program?

Possibly.

A new CPU may not contain your application. Upload the existing project before replacement and be prepared to download it to the replacement controller during commissioning.

Q3. Is the IC695CPU320HU compatible with older RX3i systems?

In most cases, yes.

The CPU320 family was designed for the RX3i platform and is compatible with existing RX3i backplanes and many installed I/O modules. However, firmware compatibility, Proficy Machine Edition version, and module revision should always be verified before installation.

Q4. What software is required for configuration?

Use Proficy Machine Edition (PME) that supports the installed CPU firmware. Before upgrading either the CPU firmware or the engineering software, review the compatibility matrix to avoid project conversion issues.

Q5. Why are New Surplus CPUs often less expensive than OEM list price?

Many New Surplus units originate from canceled projects, system upgrades, or excess inventory. They are unused but may not include the original manufacturer’s warranty. Request the serial number, inspection report, and functional test documentation before purchasing.

Q6. What quality inspections should be completed before shipment?

For production-critical applications, request:

• OEM serial number verification
• Visual inspection for corrosion, scratches, or rework
• Power-on testing in a genuine RX3i rack
• Serial communication verification
• Continuous burn-in testing for at least 24 hours
• Insulation resistance testing (>10 MΩ at 500 V where applicable)
• Firmware revision documentation
• ESD-safe packaging with QC sign-off

Test photographs and commissioning videos are valuable when planning a tightly scheduled plant outage.