Castles Vega 3000 Compatible Battery 3.7V 3400mAh V3M2

Castles Vega 3000 / Vega 3000P — 3.7V Li-ion Replacement Battery (V3M2)

This 3.7V 3400mAh Li-ion battery replaces the original cell in the Castles Vega 3000 and Vega 3000P mobile payment terminals. It matches the OEM part numbers V3M2, 40100023, and B16. Swap it in when the original cell no longer holds enough charge to complete a normal transaction session.

• Vega 3000 and 3000P compatibility: Both models run the same 3.7V single-cell architecture with the same physical connector and BMS handshake protocol. One battery fits both variants without modification.
• Bench tested on actual hardware: We cycled this battery through full charge and discharge on a Vega 3000 unit. The BMS accepted the cell, reported state-of-charge correctly, and held voltage within spec across combined display, wireless, and printer draw.
• First-use calibration on Vega 3000: After fitting this battery, complete at least one full transaction cycle — receipt print included — before deploying in a live environment. The terminal maps battery capacity during normal use and needs one complete power cycle to calibrate the charge indicator accurately.

Payment terminal rebooting mid-transaction after battery swap

When the receipt printer fires, it draws a short, sharp current spike — often 1.5A or more in under 100 milliseconds. On a new cell that hasn't completed its first charge cycle, the BMS may read this spike as an overcurrent event and trip the output. The terminal cuts power, the transaction fails, and the display restarts. Run the terminal through a full charge cycle first, then process a test transaction with a printed receipt before going live.

Terminal not powering on after sitting unused in a drawer

Li-ion cells self-discharge at roughly 2–3% per month. A Vega 3000 left unused for several months can drain the cell below the BMS recovery threshold — typically around 2.5V. At that point the BMS locks the output and the terminal shows nothing when you press the power button. Connect the terminal to its original charger and leave it for 30–45 minutes without pressing any buttons; most BMS units will re-initialise once the cell climbs back above 2.8V.