About this replacement
Bosch GLM120C / GLM150-27C — 3.7V Li-Polymer Replacement Battery (1600A00E0F)
This is a 3.7V, 2450mAh lithium-polymer replacement battery for the Bosch GLM120C and GLM150-27C laser distance meters. It fits the internal battery bay directly and matches the original cell dimensions of 67.20 × 41.70 × 9.00mm. The OEM part number is 1600A00E0F.
- GLM120C and GLM150-27C compatibility: Both meters run on the same 3.7V single-cell Li-Polymer pack with identical physical footprint and connector pinout. The BMS handshake on each model uses the same voltage thresholds, so one pack serves both without modification.
- Bench tested on actual hardware: We cycled this pack through the GLM120C's laser-on measurement loop and monitored BMS cutoff behaviour under sustained sensor load. Cell voltage held within spec across repeated measurement bursts with no unexpected shutdowns.
- Post-install calibration on the GLM120C and GLM150-27C: After fitting a new pack, run a full calibration cycle through the instrument menu before field deployment. The meter maps battery state during that sequence — skipping it causes premature low-battery warnings to appear during your first measurement session on site.
BMS lockout after the GLM120C sat unused in a carry case for months
Li-Polymer cells self-discharge slowly during storage. If the pack drops below approximately 2.5V per cell, the BMS trips into protection mode and refuses charge input entirely. The meter powers on briefly — or not at all — and the charger shows no activity. To recover the pack, apply a low-current trickle charge at around 0.05C until cell voltage climbs above 2.8V, then resume normal charging. Most chargers with a recovery or "boost" mode handle this automatically.
GLM120C powers on but shuts off during USB data transfer to a PC
USB data transfer runs the laser controller, display backlight, and USB interface simultaneously — a combined load the BMS can trip on if the cell is partially discharged or degraded. The shutdown is a protection event, not a firmware fault. Charge the pack to at least 3.9V before initiating a transfer session. If shutdowns continue on a fully charged pack, the cell capacity has faded below the threshold the BMS considers safe for that combined draw.