GeoMax ZBA-100 ZTS 602LR Replacement Battery 6V 3600mAh

GeoMax ZTS 602LR — 6V Ni-MH Replacement Battery (ZBA-100)

This is a 6V 3600mAh Ni-MH replacement for the GeoMax ZTS 602LR total station. It fits the ZBA-100 battery bay directly and restores full instrument operation. Capacity figure is taken from product data — 21.6Wh.

• ZTS 602LR compatibility: The ZTS 602LR draws steady current through its angle encoder, EDM module, and display simultaneously. This pack matches the 6V rail and connector pinout that the instrument's BMS handshake expects — voltage too high or too low and the instrument refuses to boot.
• Bench tested on actual hardware: We cycled this pack through the ZTS 602LR's full power-on sequence, including EDM initialisation and servo motor engagement at startup. The BMS held stable through the inrush spike and did not trip into protection mode.
• Post-install calibration cycle: After fitting this pack, run a full calibration sequence through the instrument menu before taking the unit into the field. The ZTS 602LR maps battery state during calibration — skip this step and the low-battery warning triggers prematurely on the first measurement session, even with a full pack.

EDM module power-up spike tripping BMS on the ZTS 602LR

The ZTS 602LR's EDM (electronic distance measurement) module draws a sharp current spike the moment it initialises — higher than steady-state operating draw. Aged Ni-MH cells with elevated internal resistance see a voltage dip at that spike, which the BMS reads as a fault and shuts the pack down. This replacement pack uses fresh cells with lower internal resistance, which keeps the voltage above the BMS cutoff threshold during that inrush event. If the instrument still cuts out at EDM startup, check that the battery contacts are clean and seating fully — poor contact adds resistance that mimics a degraded cell.

ZTS 602LR not recognising pack after months in storage

Ni-MH cells self-discharge over time, and a pack left unused for several months can drop below the voltage threshold the ZTS 602LR needs to recognise and communicate with the battery. The instrument may power on briefly then cut off, or show no battery indicator at all. To recover, place the pack in the charger for a full charge cycle before inserting it into the instrument — do not attempt a field session on a freshly installed pack that has been in storage. If the charger also fails to detect it, look for a recovery or conditioning mode on your charger and run that first; the target recovery entry voltage for most 6V Ni-MH packs is approximately 4.8V.