Mitsubishi FX-EEPROM-4 PLC Memory Cassette

FX-EEPROM-4 In Stock Now — Every Hour of Downtime Costs You Money

Your MELSEC FX-series line is down. The CPU is throwing a memory error, the program is gone, and your maintenance team is staring at a blank screen. You’ve already lost the first shift. The FX-EEPROM-4 is the exact OEM memory cassette that puts your machine back in cycle — no firmware gymnastics, no compatibility guesswork. We ship from Xiamen within 24 hours. DHL Express puts it on your bench in 2–4 business days, anywhere on the planet.

This is not a substitute. This is not a clone. This is the Mitsubishi Electric factory part, sourced through verified channels, inspected before it leaves our warehouse.

URGENT REQUIREMENT? Contact: [email protected] | WhatsApp: +86 18359268345

Quick Technical Datasheet

Troubleshooting & Replacement Tips

Symptom: CPU LED flashing, program lost after power cycle
Nine times out of ten this is a dead backup battery combined with no EEPROM cassette installed. The FX-series CPU RAM is volatile — without a charged battery or an EEPROM cassette, the program evaporates the moment mains power drops. Fit the FX-EEPROM-4 and the problem is permanently solved.

Step-by-step replacement procedure:

• Step 1 — Safe power-down: Set the RUN/STOP switch to STOP. Confirm all outputs are de-energized before cutting control power. Do not hot-swap the cassette — the FX-series memory bus is not designed for live insertion.
• Step 2 — Remove old cassette: Open the front cover of the FX CPU. Press the cassette release tab and slide the old module straight out. Inspect the connector pins for corrosion or bent contacts before inserting the new unit.
• Step 3 — Insert FX-EEPROM-4: Align the cassette guide rails and push firmly until the retention clip clicks. There is only one correct orientation — the keyed connector prevents reverse insertion.
• Step 4 — Write-protect check: The FX-EEPROM-4 has a write-protect switch on the cassette body. Confirm it is in the WRITE-ENABLE position before attempting to download a program. After download, flip to PROTECT to prevent accidental overwrite in production.
• Step 5 — Program download: Connect your programming cable (SC-09 RS-232 or USB-SC09-FX). Open GX Developer or GX Works2, select the correct FX CPU type, and execute PLC Write. Verify the step count matches your source file — a mismatch indicates a project type error.
• Step 6 — Verify and run: Set RUN/STOP to RUN. Monitor the first 10 scan cycles for unexpected output states. Check D-register values if your program uses retained data — EEPROM retains program only; data registers revert to default unless explicitly initialized in the program.

Common fault codes on FX2N with missing/faulty memory cassette:

• Error LED solid ON + M8060 set: PC memory checksum error — program in RAM is corrupted. Download fresh from EEPROM or PC backup.
• M8065 set (I/O configuration error): Unrelated to memory cassette — check extension module wiring.
• CPU won’t enter RUN after cassette swap: Confirm write-protect switch position and that the cassette is fully seated. A partially inserted cassette causes intermittent bus errors that mimic CPU faults.

Write cycle management: The FX-EEPROM-4 is rated for approximately 10,000 write cycles. In a normal production environment where the program is written once and locked, this limit is effectively irrelevant. In R&D or commissioning environments with frequent program changes, track your write count. Mitsubishi does not expose a write cycle counter via GX Developer — maintain a manual log if longevity is critical.

Reliability in Harsh Conditions

The FX-EEPROM-4 was engineered for the same industrial environments where the FX-series CPU itself operates — not a climate-controlled server room, but a factory floor with vibration, thermal cycling, and humidity that would kill consumer-grade electronics in weeks.

The EEPROM cell array is inherently immune to the failure mode that kills battery-backed RAM: battery depletion. There is no electrochemical component to degrade, leak, or corrode the PCB. The cassette has survived decades of deployment in textile mills, food processing lines, and automotive stamping presses — environments where ambient temperatures swing 30°C between morning startup and afternoon peak load, and where coolant mist and cutting fluid vapor are facts of life.

Vibration resistance is a function of the cassette’s mechanical retention design. The clip-lock mechanism keeps the connector interface under constant positive pressure, preventing the micro-fretting corrosion that plagues edge-card connectors in high-vibration applications. Units that have been in service for 15+ years in packaging machinery routinely read back their programs without error.

For installations in particularly aggressive environments — coastal facilities with salt air, chemical plants with solvent vapors — we recommend applying a thin bead of conformal coating around the cassette slot perimeter after installation. This is a field-proven practice that extends connector life without affecting cassette removal for future program updates.

Global Express Logistics

Our warehouse is located in Xiamen, Fujian Province — one of China’s primary export hubs with direct access to DHL, FedEx, and UPS international gateways. When you place an urgent order before 18:00 CST, the unit ships the same business day. No exceptions, no excuses.

• DHL Express Worldwide: 2–4 business days to Europe, North America, Southeast Asia, Middle East. Real-time tracking from pickup to delivery.
• FedEx International Priority: 1–3 business days to the US, Canada, Mexico. Preferred for North American customers with hard deadlines.
• Export documentation: Commercial invoice, packing list, and HS code 8473.30 declaration included with every shipment. EAR99 classification — no export license required for standard destinations.
• Customs clearance: We declare accurate values and correct HS codes on every shipment. We do not under-declare. This protects you from customs holds that would defeat the entire purpose of express shipping.
• Emergency freight: For genuine production emergencies requiring next-flight-out courier, contact us directly via WhatsApp. We have handled same-day airport-to-airport arrangements for customers facing multi-million-dollar line stoppages.

Contact Information

Email: [email protected]
WhatsApp: +86 18359268345
Web: siemensplc.com
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