About this replacement
Legrand 061096 / U34 LED / ECO2 — 3.6V Ni-MH Replacement Battery (GP220SCHT3BMX)
This is a 3.6V, 3000mAh Ni-MH battery for Legrand emergency lighting units — specifically the 061096, U34 LED, and ECO2 fittings. It powers the backup illumination circuit when mains supply fails, keeping evacuation routes lit during outages. Capacity is 10.8Wh as supplied.
- 061096, U34 LED, and ECO2 compatibility: All three fittings share the same 3.6V charge rail, the same physical cell format (67 × 44.40 × 22.50mm), and use the same trickle-charge controller logic — which is why one cell fits all three without modification.
- Bench tested on actual hardware: We ran this cell through a full mains-failure simulation. The BMS accepted the load immediately, the charge controller transitioned from fast-charge to float correctly, and the fault LED cleared within the expected window.
- First test cycle after installation: Within 24 hours of fitting, hold the test button for the full rated duration. This confirms the cell accepts load under discharge conditions and lets the charge controller register the new cell before your next compliance inspection — skipping this step is the most common cause of a failed duration test.
Charge indicator staying red after new battery installation
A freshly shipped Ni-MH cell often sits at a resting voltage outside the float acceptance window of Legrand's charge controller. When the controller reads this voltage on first connection, it holds the fault state rather than entering normal charge mode. This is not a faulty cell — it is the controller waiting for the cell voltage to climb into its acceptance band, which usually happens within two to four hours of connection. If the indicator has not shifted to green after six hours, disconnect the cell, wait 60 seconds, and reconnect to force the controller to re-read the cell voltage from scratch.
Emergency light dims and cuts out partway through a duration test
This symptom usually appears when the cell has not completed a full conditioning charge before the test is run. A Ni-MH cell that has been in storage delivers reduced capacity on its first discharge — the electrochemical plates have not fully re-activated. The fix is to let the fitting charge uninterrupted for a minimum of 24 hours after installation, then run the test. If dimming still occurs after a full charge cycle, check the cell contacts for oxidation and verify the float voltage at the terminals is sitting at 4.2–4.5V before triggering the test.