OTIS FFA718B1 Emergency Light Replacement Battery 6V 2000mAh

OTIS 2000 / Emergency Power Supply ECU 2 — 6V Ni-CD Replacement Battery (FFA718B1)

This is a 6V, 2000mAh nickel-cadmium replacement cell for the OTIS 2000 emergency lighting unit and Emergency Power Supply ECU 2. It fits fittings that reference OEM part numbers FFA718B1 and FFA718B1-W. This battery maintains backup illumination in elevator cabs and emergency exit routes during mains failure.

• OTIS 2000 and ECU 2 compatibility: Both units share the same 6V NiCd cell format, connector pitch, and float charge voltage. Either fitting accepts this cell without modification to the charge circuit.
• Bench tested on actual hardware: We cycled this cell through a full mains-fail simulation. The charge controller accepted the cell, completed its trickle charge phase, and the fitting advanced to green status within the expected window. BMS cutoff did not trigger during load.
• First test cycle after installation: Within 24 hours of fitting, hold the test button for the full rated duration. NiCd cells shipped from storage carry a partial charge. Running one complete test cycle lets the charge controller register actual cell capacity before the next scheduled compliance inspection.

Emergency light failing its duration test after battery replacement

A freshly installed NiCd cell does not arrive at full capacity. Storage self-discharge and the absence of a conditioning cycle both reduce available energy on the first test. The fitting's charge controller needs one complete charge-discharge cycle to measure actual cell capacity. Run a full manual test within 24 hours of installation, allow the fitting to recharge completely, then re-test — duration performance improves substantially on the second cycle.

Charge indicator staying red after confirmed good installation

The charge controller in these fittings uses float voltage to determine cell state. A cell that has been in storage long enough may present a terminal voltage outside the controller's acceptance window, causing the fault LED to hold even when the cell is physically sound. Leave the fitting connected to mains for 12–24 hours — the trickle charge will bring cell voltage into the float acceptance band and the indicator should advance to green. If the fault LED persists beyond 24 hours, measure cell voltage directly; a healthy NiCd cell at float should read at or above 6.0V.