I. Model and Version

Model: JANCD-MB20B (Yaskawa PCB Motherboard)

Original Version: JANCD-MB20 (Rev A01, Part Number DF8101356)

Version B Improvements:

Optimized backplane bus driver, reduced communication error rate

Strengthened power supply filtering, reduced ripple interference

Extended battery backup circuit lifespan

Compatible with all J300 daughterboards (PC20/MM20/JIF10/JSPxx)

II. Core Functions (Same as MB20, with stronger performance)

System Motherboard: Carries CPU, memory, communication, spindle, etc. daughterboards

Backplane Bus: 40-pin dedicated bus, connects all modules

Power Management: DC24V input, distributes power to all daughterboards

Data Backup: 5.5V lithium battery interface, saves parameters and programs

Interface Integration: Operation panel, RS-232C, I/O bus, battery, power supply

III. Key Parameters (Typical values for Version B)

Power Supply: DC24V ±10%, power consumption approximately 50W

Backplane Slots: 6 (CPU / memory / communication / spindle ×2 / reserved)

Battery: NEC 5.5V lithium battery (lifespan 2–3 years)

Operating Temperature: 0–50℃ (A version 0–45℃, B version better with high-temperature resistance)

Size / Weight: Approximately 250×220×30mm / 2.5kg

IV. Differences from MB20 (A version)

MB20 (A): Initial version, 0–45℃, general anti-interference, prone to ALM01 alarm

MB20B (B): Upgraded version, 0–50℃, strong anti-interference, significantly reduced ALM01 alarm; can be directly replaced with A version, no need to rewire

V. Compatible Systems and Common Combinations

Numerical Control: YASNAC J300 (lathe / machining center)

Robotics: JZNC-RK20 (handling / arc welding / painting)

Typical Configuration:

MB20B (Motherboard) + PC20 (CPU) + MM20 (Memory)

JIF10 (Communication) + JSP04/JSP11 (Spindle)

VI. Common Alarms and Handling

ALM01 (Bus Error): Rarely occurs in Version B; check daughterboard connections are tight, gold fingers are clean

ALM02 (Low Battery): BAT light on → Replace 5.5V lithium battery

ALM03 (CPU Exception): Reinsert PC20, check power supply

VII. Replacement and Compatibility

Replacement: MB20B can directly replace MB20 (A version), fully compatible

Note: After replacement, re-tighten all daughterboards to avoid poor contact