Product Core Brief

• Model:
• Brand: GE Fanuc / Emerson Automation
• Series: Series 90-30 PLC
• Core Function: High-performance single-slot CPU (CPU374 PLUS) for Series 90-30 main racks. Executes control logic, manages local and remote I/O racks. Integrates dual-port 10/100 Ethernet with internal switch, hardware floating-point arithmetic.
• Product Type: Single-width Series90-30 CPU Module
• Key Specs: 133 MHz AMD SC520 processor | 240KB user memory | Dual switched 10/100 Ethernet | Hardware floating-point | Supports EZ Program Store offline program download Note: Discontinued flagship Series90-30 CPU; new original stock scarce, surplus & refurbished widely available. -GU = Conformal coated PCB variant for humid, corrosive cabinet environments. CPU cannot support hot swap. Install directly on IC693CHS backplanes. No onboard serial ports; serial communication relies on power supply RS485. Not plug-compatible with RX3i backplanes. Standard non-coated version: .

 

Key Technical Specifications

• Processor: 133 MHz AMD SC520
• Typical Boolean Scan Time: 0.15 ms per 1000 boolean contacts
• Supported Programming Languages: LD, FBD, ST, IL, C program blocks
• Memory 240 KB user logic/data memory Flash program storage; IC693ACC302 lithium battery for RAM & RTC retention
• I/O Capacity Discrete: Max 4096 total (%I / %Q) Analog: Max 512 total (%AI / %AQ)
• Onboard Communication Interfaces Dual RJ45 10/100BASE-T-TX with built-in internal Ethernet switch (single IP address) No onboard serial ports; serial SNP/Modbus RTU via power supply RS485 port
• Supported Protocols Ethernet: SRTP, EGD, Modbus TCP Client/Server, SNTP Serial: SNP/SNPX, Modbus RTU Master/Slave
• Backplane Power Consumption 5 VDC: 1.48 A (7.4 W)
• Front Panel LED Indicators: CPU OK, RUN, SYS FLT, LAN1, LAN2, ETHERNET RESTART
• Hardware Switch: RUN / STOP / Memory Protect
• Offline Program Support: Compatible with EZ Program Store storage device
• Maximum Rack Scale: Up to 8 racks total (main rack + 7 expansion racks)
• Operating Temperature: 0°C ~ +60°C horizontal cabinet mounting
• Storage Temperature: -40°C ~ +85°C
• Form Factor: Single-width module for IC693 Series90-30 backplane
• Compatible Baseplates: IC693CHS391 (5-slot), IC693CHS392 (10-slot)
• Supported Software: Logicmaster 90, Proficy Machine Edition
• Agency Certifications: UL508, Class I Div.2, CE, ATEX Zone 2

 

Product Introduction

is the top-tier flagship CPU of the Series 90-30 platform, known as CPU374 PLUS. The most prominent feature is dual switched Ethernet ports, allowing PLC daisy-chain topology without external network switches.

Suffix Explanation

• : Conformal coated PCB variant, improved protection against dust, moisture and corrosive gas for harsh cabinets
• : Standard non-conformal coated commercial version Functionally and electrically identical, fully interchangeable.

Critical CPU Family Comparison

1. : 133MHz, dual switched Ethernet, hardware floating-point, EZ Program Store support
2. IC693CPU364: 25MHz, single 10M Ethernet, slower scan speed
3. IC695 CPU/CPE series: Native RX3i CPUs, different mechanical form factor, cannot directly replace Series90-30 CPUs

Important Wiring Limitation: No onboard serial ports. Serial expansion Genius bus or serial Modbus RTU must utilize the RS485 terminal on the IC693 power supply module.

 

QA & Testing SOP (Transparency Building)

1. Incoming Inspection: Verify part marking and -GU conformal coated suffix. Inspect backplane gold pins for oxidation/bending; inspect dual RJ45 ports and housing integrity. Avoid scratching conformal coating.
2. Live Testing: Mount onto validated IC693CHS backplane. Apply rack power, download test program, verify Ethernet communication and module recognition in Proficy Machine Edition, run continuous 24-hour rack stability test.
3. Electrical Testing: Monitor backplane 5V rail load; insulation resistance ≥10MΩ between circuits and chassis protective ground.
4. Documentation: Photograph Ethernet wiring and front panel switch position before disassembly.
5. Final QC & Packaging: Place unit inside anti-static shielding. Attach dated QC test tag confirming Ethernet bus and backplane communication validation prior to shipment.

 

Installation Pitfalls & Guide

❗ No Hot Swap Support: CPU module cannot be hot swapped. Full rack power shutdown mandatory before removal. ❗ Dual Ethernet Restriction: Single IP address for both switched ports; cannot assign separate IP addresses for LAN1 and LAN2. ❗ No Onboard Serial Port: Do not expect serial communication directly from CPU front panel; serial bus uses power supply RS485. ❗ Power Budget Calculation: Total module power draw must not exceed IC693 power supply rating; CPU374 consumes relatively high 5V current. ❗ Conformal Coating Care: Prevent PCB coating scratches during handling; damaged coating degrades environmental protection. ❗ EMC Grounding: Proper chassis shielding ground to suppress Ethernet noise and static discharge. ❗ EZ Program Store Note: Use supported GE industrial storage device for offline program loading.

Replacement Guide

1. Pre-install: Lockout-tagout rack power; back up complete PLC project. Photograph slot arrangement, Ethernet wiring and power module position.
2. Removal: Power off rack, extract CPU from backplane, disconnect all Ethernet cables.
3. Instew into original slot on IC693CHS backplane, replicate Ethernet wiring.
4. Power-on Test: Restore rack power; confirm CPU OK LED steady, connect PME, verify Ethernet communication, I/O scanning and all network data exchange.

 

FAQ

es support hot swapping? A: No. CPU modules on Series90-30 backplanes do not support hot swap. Full rack power shutdown required.

Q: What does the -GU suffix mean? A: -GU = Conformal coated PCB variant for humid, corrosive industrial cabinet environments. Standard has no coating. Fully interchangeable.

Q: What is the main diffeen and IC693CPU364? A:

• CPU374-GU: 133MHz, dual switched Ethernet, hardware floating-point, faster scan speed, supports EZ Program Store
• CPU364: 25MHz, single 10M Ethernet, slower performance Not plug-and-play direct replacement; program memory and performance differences require validation.

Q: ll directly into RX3i IC695CHS007 rack? A: No. Mechanical and backplane bus incompatible. It is native Series90-30 CPU.

Q: Can the two Ethernet ports be used for separate network segmentation? A: No. Internal switch, single IP address; suitable for daisy-chain topology only.

Q: Does this CPU support HART communication? A: No native HART capability; use external HART analog modules.

Q: Will program configuration automatically work after CPU replacement? A: Program resides inside CPU flash memory. Always back up project before replacing CPU; re-download program to new CPU.