About this replacement
Tyro Indus 1S Wireless E-stop — 3.7V Li-ion Replacement Battery (U80526-1)
This 3.7V, 1800mAh Li-ion cell replaces the factory battery in the Tyro Indus 1S Wireless E-stop remote (OEM part U80526-1). The Indus 1S is a wireless emergency stop transmitter used in crane and material handling operations. Voltage and capacity match the original specification exactly.
- Indus 1S transmitter fit: The U80526-1 cell runs the wireless transmitter circuit at 3.7V nominal. The BMS on this cell communicates state-of-charge to the remote's onboard controller, which drives the low-battery indicator before cutoff kicks in. No voltage mismatch, no connector modification needed.
- Bench tested on actual hardware: We cycled this cell through repeated E-stop activation sequences and monitored BMS cutoff behaviour under the inrush current spikes that occur during solenoid trigger events. Voltage held steady across the test window with no unexpected dropouts.
- Monthly charge during idle periods: Crane remotes often sit unused for weeks between jobs. Li-ion cells discharged below 2.5V enter deep-discharge lockout — the BMS disables output and many chargers will not initiate a charge cycle. Connect the remote to its charger once a month during any extended storage period to keep the cell above that threshold.
Why the Indus 1S won't power on after months of infrequent use
Li-ion cells have a self-discharge rate of roughly 2–3% per month. After several months on a shelf, the cell voltage can drop below 2.5V — the point at which most BMS circuits open the protection circuit and block output entirely. At that voltage, the remote shows no signs of life: no LED, no RF transmission, no response to the power button. Connecting the charger for 30 minutes allows a quality charger to trickle current into the cell, nudging voltage above the BMS recovery threshold before normal charging resumes.
Remote showing low battery alert immediately after fitting a new cell
Replacement cells ship at storage voltage — typically 3.6–3.7V — not fully charged. Some remotes interpret anything below 3.8V as a low-battery condition and flag it immediately after power-on. This is not a fault with the cell. Charge the battery fully before first use; the alert will clear once the cell reaches approximately 4.1–4.2V under the charger.