Beghelli 8823 Emergency Light Replacement Battery 6V 2000mAh

Beghelli 8823 / 391848 / 784157 — 6V Ni-CD Replacement Battery (MGN9021)

This is a 6V 2000mAh Ni-CD replacement battery for the Beghelli 8823 emergency lighting unit and compatible fittings including the 391848, 784157, and B171/515. It slots into the fitting's battery bay and connects to the existing charge controller. Capacity is 2000mAh (12Wh) — use these figures for any compliance documentation, not values from third-party listings.

• Fitting compatibility across the 8823 series: These models share the same 6V charge rail, connector pin layout, and float charge voltage. The charge controller does not perform a BMS handshake — it reads terminal voltage directly, so cell chemistry and voltage must match exactly.
• Bench tested on actual hardware: We ran this cell through a full charge cycle and load discharge on a Beghelli-compatible 6V emergency lighting circuit. The cell accepted charge without voltage excursion and held stable terminal voltage throughout the load phase.
• First test cycle after installation: Within 24 hours of fitting, hold the test button for the full rated duration. This lets the charge controller register the new cell and confirms the cell accepts load before your next scheduled compliance test.

Emergency light failing its duration test after battery replacement

A new Ni-CD cell ships in a partially discharged state from storage. The charge controller in the 8823 applies a float charge — it does not run a conditioning cycle. Until the cell has completed at least one full charge-discharge cycle, it will not deliver its rated 2000mAh under load. Run the test button cycle within 24 hours of installation, allow the fitting to recharge fully, then retest. A cell that still fails after two full cycles should read at least 5.8V under load — anything below that points to a fault in the fitting's charge circuit, not the cell.

Charge indicator staying red after a confirmed good installation

If the fitting's charge LED stays red after the new cell is installed, the cell's resting voltage from storage may be outside the float acceptance window the controller expects. The 8823's charge controller can interpret a low resting voltage as a fault condition rather than a discharged cell. Leave the fitting powered for 12–16 hours and check the LED again — most controllers will accept the cell once terminal voltage climbs above 5.4V. If the LED remains red past 24 hours, confirm the cell connector is fully seated and the terminal contacts are clean.