4K CMOS Logic Memory Module, Battery-Backed — Series Six Model 600 / 6000, BATTERY and PARITY LEDs, No Battery Supplied

What this part is:
A GE Fanuc IC600CM544A, the 4K CMOS logic memory module for the Series Six programmable logic controller. This is the card that holds the user program — the ladder logic — and the register memory for the controller. It is catalogued specifically for use in the Model 600 or Model 6000 Series Six PLCs.

Because the memory is CMOS and battery-backed, register memory is retained after a power failure or a deliberate power-down. That is the defining behaviour of the card and it is why the module carries a battery status indicator.

Where it sits in the Series Six memory range:
GE Fanuc offered the same card in three capacities, and the only difference between them is how much program they hold:

IC600CM542 — 2K CMOS logic memoryIC600CM544 — 4K CMOS logic memory (this module), for Model 600 or 6000IC600CM548 — 8K CMOS logic memory, for Model 600 or 6000
The practical consequence is straightforward but worth stating: a larger card will hold a smaller program, but a 4K card will not hold a program written for an 8K machine. If your ladder was developed on a CM548 you cannot drop back to this module without cutting the program. Check your program size before ordering, not after.

Correcting the source data:
Our record carried no brand at all and described the module only as “a unit manufactured in the United States” providing “memory storage and logical functionality.” The correct manufacturer of record for IC600-prefix hardware is GE Fanuc Automation — the GE–Fanuc automation joint venture whose product line became GE Intelligent Platforms and then Emerson. The “Made in USA” note on our condition record is consistent with that and has been echoed unchanged.

A second thing worth telling you plainly: the photographs on this record are shared with another Series Six memory listing in our catalogue and may not be of this exact module. They are representative of the Series Six CMOS memory card family rather than verified images of this specific unit. If the physical condition, the revision suffix or the presence of a battery matters to your purchase — and on a memory card it reasonably might — ask us and we will photograph the actual item on the shelf. We would rather flag that than let a shared image stand as a claim.

Published data:
Type: CMOS logic memory module, battery-backedCapacity: 4KPlatform: GE Fanuc Series Six, Model 600 or Model 6000Functional levels: usable with the basic, extended, advanced and other functional levelsConstruction: two-tier circuit boardIndicators: BATTERY and PARITY status LEDsRetention: register memory retained through a power failure or power-down, by battery backup
Backplane current draw, memory retention time on a fresh battery, battery type and part number, operating temperature and module dimensions are not published in any source we could verify. The authority for them is the GE Fanuc Series Six PLC Datasheets Manual, GEK-25367, which Emerson still distributes. We have left those cells blank rather than borrow figures from an adjacent card in the same manual.

The battery is the part that will let you down:
This deserves its own heading because it is the single most common failure on a battery-backed memory card, and it is entirely avoidable.

No battery is supplied with this module. On a card that has spent years in storage, any battery that is physically present is long flat and may have leaked — alkaline and lithium cells both damage PCBs and connectors when they vent, and the damage is often invisible until the card is powered. Before fitting a stored memory card, inspect the battery holder and the surrounding board for residue and corrosion, and fit a fresh cell.

The two LEDs on the faceplate are your diagnostic. BATTERY warns that backup is failing — treat it as a scheduled job, not an alarm to acknowledge, because when it finally goes you lose the program. PARITY indicates a memory data error; a parity fault on a card that has just been fitted usually means the program load did not complete or the card is faulty, and a parity fault that appears in service on a previously good card usually means the memory has started to fail.

The corollary, which is worth saying to anyone buying a spare: a memory card is not a backup. Have your ladder program archived independently before you swap one.

What is not included:
Module only. Not included: the backup battery, the Series Six CPU rack and backplane, the CPU, the rack power supply, any programming device or software, and the user ladder program. We make no claim that any program is present on this module.

Quantity and interchange guidance:
Two units in stock, sold individually — one to fit and one to hold, which on a memory card carrying a plant’s ladder logic is a sensible way to buy.

Search forms include IC600CM544A, IC600CM544, IC600-CM-544-A, IC600-CM-544, IC600 CM 544 A, IC600CM54 and IC600CM5. Related Series Six modules: IC600CM542 (2K), IC600CM548 (8K), and the IC600BF942 four-channel analogue output card that shares the same racks. The A suffix is a revision level; match the base number first.

Series Six is fully obsolete with no factory replacement, retired well before Emerson acquired GE Intelligent Platforms. Ownership trail: GE Fanuc Automation → GE Intelligent Platforms → Emerson. Reman modules and board-level repair remain available, and for a plant still running Series Six that is normally far cheaper than migrating the control.