Product Introduction
In continuous process industries, “downtime” is just a polite word for lost revenue and potential safety incidents. The GE IC695CRU320 is engineered specifically to eliminate that word from your vocabulary. As the redundancy processor for the PACSystems RX3i platform, it doesn’t just run logic; it actively mirrors the state of its partner CPU, ensuring that if one fails, the other takes over in less than 3.2 milliseconds.This isn’t a standard PLC upgrade; it’s an insurance policy for your critical infrastructure. With a 1GHz Celeron-M processor and 64MB of battery-backed RAM, the IC695CRU320 handles complex PID loops and high-speed interlocks without breaking a sweat. I’ve deployed these in water treatment plants and chemical reactors where the cost of a single missed scan cycle could be catastrophic. The dual serial ports (RS-232/RS-485) also make it a versatile bridge for legacy field devices, keeping your old sensors talking to your new SCADA.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Processor | Intel Celeron-M @ 1GHz |
| User Memory | 64 MB Battery-Backed RAM |
| Non-Volatile Memory | 64 MB Flash |
| Redundancy Switchover | Max 1 Logic Scan / Min 3.133 ms |
| Serial Ports | 2x Integrated (RS-232 & RS-485) |
| Backplane Interface | PCI 2.2 (High-Speed Data Transfer) |
| Max Program Blocks | 512 Blocks (128KB each) |
| Sync Link Support | Up to 2x IC695RMX128/228 |
| Power Consumption | 1A @ 3.3VDC, 1.2A @ 5VDC |
| Programming | Ladder Logic, C, Function Block Diagram |
Application Scenarios & Pain Points
The IC695CRU320 is built for the environments where “maybe it will work” is not an acceptable answer. I’ve seen plants try to save money by using single CPUs on critical lines, only to spend ten times that amount on emergency air freight and overtime when a capacitor fails at 2 AM. This module solves the single-point-of-failure problem at the hardware level.
- Oil & Gas Pipelines: For remote pump stations, the IC695CRU320 ensures that pressure relief valves respond instantly, even if the primary controller suffers a power surge. The hot standby configuration means zero process interruption during the failover.
- Power Generation: In turbine control, the 1GHz speed of the IC695CRU320 is critical for overspeed protection. The sub-4ms switchover time guarantees that safety logic never misses a beat during a grid disturbance.
- Water/Wastewater Treatment: Municipal plants often run 24/7/365. The IC695CRU320 allows you to replace or upgrade the standby CPU without shutting down the plant, turning maintenance from a nightmare into a routine task.
- Chemical Batch Processing: When a reactor is at peak temperature, you can’t afford a controller reboot. The IC695CRU320 maintains the exact process state across the redundancy link, ensuring batch consistency and safety.
Real-World Scenario: A refinery had a recurring “sync loss” fault. They replaced the CPU twice. The third time, we found the fiber optic sync cable was pinched against the cabinet door. The IC695CRU320 was perfect; the installation was not. Always check your physical layer before blaming the silicon.
Quality Control Process
We treat every IC695CRU320 as if it’s going into our own plant. Here is the verification protocol:
- Visual & Mechanical: We inspect the PCI connector pins for straightness and gold plating integrity. We check the battery holder for corrosion—a silent killer of RAM retention. We verify the serial port housings are not cracked.
- Redundancy Switchover Test: We install two IC695CRU320 units in a test rack. We force a primary CPU fault and measure the actual switchover time with an oscilloscope. It must be under 3.2ms. If it hiccups, it fails.
- Memory Stress Test: We write and read the full 64MB RAM and Flash repeatedly to check for bad blocks. We then pull power for 60 seconds and verify the battery holds the logic without corruption.
- Communication Check: We verify both RS-232 and RS-485 ports under load. We send continuous Modbus traffic for 4 hours to ensure no buffer overflows or UART lockups.
- Firmware Verification: We read the exact firmware revision. Critical: Redundancy requires matching firmware. We document this on the shipping label so you don’t waste time troubleshooting a version mismatch.
Installation Pitfalls Guide
I’ve walked too many sites where a simple oversight turned a 1-hour swap into a 2-day commissioning disaster. Watch out for these:
- ❗ Sync Cable is Not Ethernet: The IC695CRU320 uses proprietary sync links (IC695RMX128/228). Do not plug a standard CAT6 cable into these ports. You will fry the transceivers. Use only GE-specified fiber or copper sync cables.
- ❗ Battery Installation: The IC695CRU320 requires an external high-capacity battery (IC693ACC302). If you power up without it, or with a dead one, the CPU will fault immediately. Install the battery before applying backplane power.
- ❗ PCI Slot Seating: This is a 2-slot wide module on a PCI backplane. If you feel resistance, stop. Forcing it bends the PCI pins. Wiggle it gently until it seats flush. A 0.5mm gap can cause intermittent sync loss.
- ❗ Firmware Mismatch: You cannot mix IC695CRU320 firmware versions in a redundant pair. If your standby is V4.5 and primary is V4.2, they will not sync. Always match the exact revision of the surviving CPU.
- ❗ Ground Loops: The RS-485 port is sensitive to ground potential differences. If you’re connecting to a remote panel, use an isolated repeater. I’ve seen ground loops fry the serial chip on a brand new IC695CRU320 within minutes of power-up.
