About this replacement
Willing Wi200552 3 VTCS — 3.6V Ni-CD Replacement Battery (197133-R13-1)
This is a 3.6V, 1500mAh nickel-cadmium replacement cell for the Willing Wi200552 3 VTCS emergency lighting unit. It fits directly into the fitting and restores backup illumination capability during mains failure events. Voltage and capacity match OEM specification 197133-R13-1.
- Wi200552 3 VTCS compatibility: This fitting uses a fixed 3.6V NiCd cell tied to an internal charge controller calibrated for NiCd float voltage. Swapping chemistry — for example, to NiMH — will cause the charge controller to overcharge or undercharge the cell, failing compliance tests.
- Bench tested on actual hardware: We ran this cell through a mains-failure simulation on the Wi200552 3 VTCS fitting. The charge controller accepted the cell without fault, the BMS registered full float charge within 24 hours, and the lamp activated at rated output on test trigger.
- Post-installation test cycle: Within 24 hours of fitting this cell, hold the test button for the full rated duration. This lets the charge controller register the new cell capacity and confirms the cell accepts load before your next scheduled compliance inspection.
Charge indicator staying red after installing a new cell
NiCd cells shipped in storage have a resting voltage that can sit outside the fitting's float acceptance window. The Wi200552 3 VTCS charge controller interprets this low resting voltage as a fault condition and holds the red indicator. Leave the fitting on mains power for a full 24-hour charge cycle before concluding there is a fault. The indicator should transition to green once the cell reaches approximately 4.2V across the pack.
Emergency light dims partway through a duration test
A cell that has not completed its first full conditioning cycle will not deliver rated capacity under sustained load. The voltage drops prematurely, the lamp dims, and the fitting fails its duration test. This is not a faulty cell — it is an uncharged one. Allow a full 24-hour charge before running any compliance test, and the cell should hold output for the full rated period at or above 3.0V under load.