6v Backup Fanuc Controller Battery Replacement A98L-0031-0026 ODM

A98L-0031-0026 | FANUC Miscellaneous Family 3V Lithium Battery — Black Modular / 0.055 lbs / CNC SRAM Backup

FANUC Miscellaneous Family — Cross-Platform Spare

The A98L-0031-0026 belongs to FANUC's "Miscellaneous" family series — the FANUC product category that groups consumable and maintenance parts shared across multiple CNC families rather than being exclusive to a single CNC model. This cross-family classification reflects the A98L-0031-0026's deployment reality:

Multiple Series 0i variants: The battery serves FS0i-MD (machining centre), FS0i-MF (advanced machining), and related Series 0i CNC configurations — different CNC applications sharing the same battery.

Common spare: Because the A98L-0031-0026 appears across multiple machine types, a single battery stock covers the maintenance requirements of a mixed fleet of FANUC FS0i-equipped machines — one part number, multiple machines.

Maintenance planning implication: A facility operating five FANUC FS0i-series machining centres of different configurations can standardise on A98L-0031-0026 for all CNC battery maintenance — simplifying spare parts inventory and reducing the risk of stocking the wrong battery for a specific CNC model.

Key Specifications

SRAM Content — Four Categories of Protected Data

With A98L-0031-0026 installed and charged, the FANUC Series 0i CNC retains four categories of SRAM content through all power-off periods:

1. NC programmes: All part programmes resident in CNC memory — immediate restart capability on power restoration.
2. Parameters: Machine-specific CNC configuration — servo tuning, axis limits, spindle data.
3. Tool offsets: All tool length and diameter compensation values in the offset table.
4. PMC ladder programme: The machine builder's programmable machine controller logic — interlocks, sequences, and machine-specific PLC programme.

Loss of any of these categories requires reload from external backup or, for parameters and ladder programme, from the machine builder's maintenance documentation — a process that can take hours.

Application Scenarios

Multi-machine preventive maintenance: A production facility runs eight FANUC FS0i-MD and FS0i-MF machining centres. The maintenance plan calls for A98L-0031-0026 replacement across all machines on the same schedule — one part number covers all machines, simplifying the parts order and maintenance execution.

New CNC installation commissioning: A newly installed FANUC FS0i CNC is commissioned and all programmes and parameters are downloaded. A new A98L-0031-0026 is installed to ensure full rated battery life protects the newly loaded CNC data from the commissioning date.

FAQ

Q1: How does A98L-0031-0026 differ from other FANUC 6V servo batteries like BR-AGCF2W?

A98L-0031-0026 is a 3V single-cell modular battery for the FANUC Series 0i CNC controller's SRAM memory backup. BR-AGCF2W is a 6V two-cell wire-lead pack for FANUC Beta servo amplifier ABS encoder backup. The two batteries serve entirely different circuits within a FANUC CNC machine tool — a machine using Beta servos needs both the CNC controller battery (A98L-0031-0026) and the servo amplifier batteries (BR-AGCF2W on each axis). They are not interchangeable.

Q2: When is the right time to replace A98L-0031-0026 in a FANUC FS0i CNC?

Replace at the low-battery alarm (alarm 9F or SW0100) regardless of how recently the last battery was installed. For proactive maintenance, a 3-year replacement interval is standard practice — replacing before the alarm eliminates any risk of production-stopping data loss. Never defer replacement once the alarm appears.

Q3: Is A98L-0031-0026 the same as A98L-0031-0028, another FANUC 3V modular battery?

Both are FANUC black modular 3V lithium batteries, but they serve different CNC families. A98L-0031-0026 (A02B-0309-K102) is for FS0i-MD/MF and related CNCs. A98L-0031-0028 (A02B-0323-K102) is for a different FANUC CNC variant — the connector or cell configuration differs. Confirm from the CNC's battery alarm message or maintenance manual which A98L specification applies.

Q4: Can A98L-0031-0026 be hot-swapped (replaced without powering off the CNC)?

Yes. With the CNC in standby or run mode, the internal power supply maintains SRAM. Remove the cartridge, insert the replacement, and verify the battery alarm clears. The 3-pin connector's positive locking ensures secure connection. Avoid removing the battery when the CNC is in power-off state unless the replacement is inserted within seconds.