About this replacement
Panic Door BP6 — 6V Alkaline Replacement Battery (DL-10)
This is a 6V 5500mAh alkaline replacement battery for the Panic Door BP6 emergency exit lock system. It powers the electronic locking mechanism and door release functions during mains power outages. OEM part numbers DL-10, BP-6, PG10, and HTL-10 all cross-reference to this unit.
- BP6 lock platform fit: The BP6 emergency exit hardware runs a 6V DC supply rail to the electronic release solenoid and control board. This battery matches that rail exactly — same connector pinout, same voltage, same form factor at 51.60 × 51.60 × 51.00mm. The locking board does not accept 4.5V or 9V substitutes.
- Bench tested on actual hardware: We cycled this battery through repeated solenoid-release events under load. The alkaline cell held voltage above the BP6 control board's minimum threshold throughout, and the BMS did not trigger a low-voltage cutoff during simulated door-release sequences.
- Post-swap access verification: After fitting this battery, test the manual release bar, the keypad or electronic trigger, and any remote override before closing the door on a live exit. The BP6 control board may require a short re-initialisation period after power interruption before all release modes respond correctly.
Why the BP6 solenoid fails to release after a power interruption
When mains power drops and the BP6 switches to battery backup, the control board draws a surge current to energise the solenoid. If the battery sitting in the unit has self-discharged below approximately 5.4V, that surge trips the low-voltage protection on the board before the solenoid fully actuates. The door appears locked even though the battery is physically present. Fitting a fresh alkaline cell at full 6V resolves this — the board gets the peak current it needs on the first release attempt.
Low-battery indicator staying on immediately after fitting a new battery
Some BP6 units latch a low-battery flag in the control board's memory when the old cell drops below threshold. Swapping the battery alone does not always clear that flag. Remove the new battery, wait 30 seconds for the board to fully discharge its capacitors, then reinsert. If the indicator persists after that, confirm the battery polarity is correct and the terminal contacts are clean — oxidised contacts add resistance that reads as low voltage to the board even at 6V.