Deviser DS2100A Replacement Battery 11.1V 1700mAh B09040066

Deviser DS2100A / DS2100B / DS2100Q / DS2100L — 11.1V Li-ion Replacement Battery (B09040066)

This is the B09040066 lithium-ion battery for Deviser DS2100 series digital theodolites and total stations. It runs at 11.1V with a 1700mAh (18.87Wh) capacity. It fits the DS2100A, DS2100B, DS2100Q, and DS2100L variants — all four share the same battery bay, connector pinout, and BMS communication protocol.

• DS2100 series compatibility: The A, B, Q, and L variants of the DS2100 all use the same 11.1V three-cell configuration, the same physical form factor, and the same BMS handshake sequence. A battery that clears the handshake on one will clear it on all four.
• Bench tested on actual hardware: We ran this pack through the DS2100's power-on sequence, sensor initialisation, and a sustained angle-measurement logging session. The BMS held through the current spike at probe power-up and maintained stable voltage under continuous sensor load throughout logging.
• Post-install calibration before field deployment: After fitting this battery, run a full calibration cycle through the instrument menu before taking it to site. The DS2100 maps battery state during calibration — skipping this step causes the instrument to throw premature low-battery warnings on the first measurement session, even with a fully charged pack.

BMS lockout after the DS2100 sat unused in a carry case for months

Li-ion cells self-discharge slowly during storage. If the DS2100 sat in a case for several months, the pack voltage may have dropped below the BMS recovery threshold — typically around 2.5V per cell, or roughly 7.5V total for a three-cell 11.1V pack. At that point the BMS enters a protective lockout and the instrument will not power on or show any charging activity. Connecting the charger for 15–30 minutes at a low trickle often recovers enough voltage for the BMS to re-initialise and accept a normal charge. If the pack does not respond after 45 minutes on the charger, the cells have dropped below the recovery floor and the pack needs replacing.

DS2100 shuts down mid-measurement with no low-battery warning

This typically happens when the instrument is running sustained horizontal or vertical angle logging with the display at full brightness — the combined sensor and display draw pulls the pack voltage below the BMS cutoff threshold momentarily, and the instrument cuts power to protect the cells. It is not a capacity failure; it is a voltage-sag event under load. Reduce display brightness one step in the instrument settings and check that the battery contacts in the bay are clean and making firm contact — corroded or loose contacts add resistance and amplify sag. If the shutdowns persist, check pack voltage under load with a multimeter: a healthy cell cluster should hold above 9.5V during active logging.