TSC1 29518 Survey Equipment Replacement Battery 7.4V 2600mAh

TSC1 Data Collector — 7.4V Li-ion Replacement Battery (29518)

This 7.4V, 2600mAh Li-ion pack replaces the original TSC1 battery used in handheld survey data collectors for construction, infrastructure, and land surveying fieldwork. It matches OEM part numbers 29518, 38403, 46607, 52030, C8872A, and EI-D-LI1. Voltage and capacity are matched to keep the instrument's power rail stable across extended logging sessions.

• Multi-OEM cross-reference: Six part numbers reference this same cell configuration — 29518, 38403, 46607, 52030, C8872A, and EI-D-LI1 all share the same 7.4V nominal rail, connector pinout, and BMS handshake. Procurement and service batches used different codes across firmware revisions, but the physical pack is identical.
• Bench tested on actual hardware: We ran this pack through probe initialisation cycles and sustained GPS logging loads. The BMS handled the current spike at sensor power-up without tripping, and voltage held above the instrument's low-battery threshold throughout the logging window.
• First-use calibration step: After installing this pack, run a full calibration cycle through the instrument menu before field deployment. The instrument maps battery state during that sequence. Skip it and the fuel gauge will throw premature low-battery warnings on the first measurement session.

Voltage dropout under sustained sensor and GPS load

TSC1 data collectors run GPS, internal sensors, and display backlight simultaneously during active survey sessions. That combined draw creates a sustained load the BMS must handle without triggering a protective cutoff. A worn or mismatched cell struggles to hold the 7.4V nominal rail under this load, causing the instrument to interpret a voltage sag as a dead pack. This replacement uses cells rated for the continuous current TSC1 instruments pull during multi-sensor logging.

Pack won't charge after months sitting unused in a carry case

Li-ion cells left uncharged for several months can self-discharge below the BMS recovery threshold — typically around 2.5V per cell. When voltage drops that low, the BMS enters sleep mode and the charger sees no response, showing no charge activity at all. Connect the pack to the TSC1 charger and leave it for at least 30 minutes before assuming the pack is faulty — most BMS circuits recover with a trickle pulse before accepting a full charge cycle. If the charger still shows no activity after 30 minutes, check cell voltage directly: anything below 5.0V total indicates the cells have gone below recoverable threshold.