Fanuc Main Board A16B-3200-0491 A16B-32OO-O491 A16B32000491

A16B-3200-0491 | FANUC Series 0i-B Main CPU Board — PMC-SB7 / Up to 6 Axes / 0i-TB and 0i-MB / SMD Modular Memory

Series 0i-B — The Second 0i Generation

The FANUC Series 0i has progressed through multiple hardware generations: 0i-A, 0i-B, 0i-C, 0i-D, and 0i-F. The A16B-3200-0491 is the main CPU board for the 0i-B generation — "the 2nd of the Fanuc Series 0i controllers" (DNC Electronics).

The 0i-B platform brought significant capability advances over the 0i-A:

• PMC-SB7 replaces the PMC-SB2 of the 0i-A generation — more ladder steps, more data registers, and a faster PMC execution cycle
• 6-axis capability supports more complex machine configurations
• Modular SMD memory architecture allows configuration flexibility for different machine requirements

The 0i-B was widely deployed on turning centres (0i-TB) and machining centres (0i-MB) worldwide.

Key Specifications

PMC-SB7 — The Sequence Controller for 0i-B

The PMC-SB7 is the Programmable Machine Controller model integrated into the 0i-B platform. In the FANUC CNC architecture, the PMC runs the machine sequence logic — the ladder programme that governs all non-cutting machine functions: coolant control, hydraulics, tool changers, door interlocks, and operator panel responses.

The "SB7" designation identifies the PMC's capability level:

• Programme steps: The PMC-SB7 provides more ladder steps than the older PMC-SB2, accommodating more complex machine sequences without programme size limitations.
• Data capacity: More D (data) and K (keep relay) registers for complex sequence logic.
• I/O capacity: Expanded I/O point addressing to handle machines with larger I/O point counts.

The PMC-SB7's integration directly on the A16B-3200-0491 main board simplifies the CNC hardware architecture — no separate PMC board is required.

Application Scenarios

0i-TB CNC main board failure: A FANUC 0i-TB turning centre loses its CNC — boot failure, persistent system alarms. The A16B-3200-0491 is identified as the fault. Memory modules are transferred to the replacement board. CNC boots with the machine's existing software and PMC programme.

0i-MB machining centre main board replacement: A 3-axis 0i-MB machining centre requires a main board replacement. The A16B-3200-0491's 6-axis capability provides headroom for this 3-axis application.

FAQ

Q1: What is the difference between the A16B-3200-0491 (0i-B) and a 0i-C or 0i-D main board?

Each 0i generation uses a distinct main board architecture. The 0i-B (A16B-3200-0491) runs PMC-SB7 and uses A16B-3200 series boards. The 0i-C uses A20B-8100 series boards. The 0i-D uses A20B-8200 series boards. These are different hardware generations — boards are not interchangeable between generations.

Q2: Can A16B-3200-0491 be supplied with or without SMD modules?

DNC Electronics confirms the board is "supplied with no SMD modules, as they make the generic version of the board specialised to the CNC machine tool." This means the correct SMD memory modules (FROM, DRAM, SRAM) specific to the installed machine configuration must be transferred from the original board or separately sourced and configured. Confirm the required module specifications from the machine's hardware documentation.

Q3: What is the maximum axis count supported by A16B-3200-0491?

MRO Electric and DNC Electronics both confirm up to 6 axes for the A16B-3200-0491. The actual axis count depends on the specific 0i-B machine configuration and software option. The standard 0i-TB (turning centre) uses 2–4 axes; the standard 0i-MB (machining centre) uses 3–4 axes. The 6-axis capability provides headroom for more complex configurations.

Q4: Does replacing A16B-3200-0491 require PMC programme backup?

The PMC ladder programme resides in the SRAM memory module — if the SRAM module is transferred to the replacement board, the PMC programme is preserved. However, always perform a complete backup of all SRAM data (parameters, PMC programme, part programmes) before any main board maintenance. If the SRAM module is also damaged, programme restore from backup is required.

Q5: What warranty is available for A16B-3200-0491?

Multiple suppliers confirm warranty coverage: MRO Electric (1-year warranty, per user data), CNC Tools LLC (12-month warranty, 100% tested). The board is actively stocked and serviced despite the 0i-B generation being mature. Repair services are also available through specialist FANUC service providers.