Horizon HKB10 Kronos C3+ Compatible Battery 7.4V 2000mAh

Horizon Kronos C3+ — 7.4V Li-ion Replacement Battery (HKB10)

The HKB10 is a 7.4V, 2000mAh Li-ion battery for the Horizon Kronos C3+ field instrument. It fits surveying, construction, and geospatial measurement workflows where the original pack has degraded or depleted. This cell matches the OEM voltage rail and connector spec of the Kronos C3+ chassis.

• Kronos C3+ platform fit: The C3+ uses a dedicated battery bay with a keyed connector and BMS handshake. This pack carries the correct cell configuration and communication lines to satisfy that handshake — the instrument will not initialise from a pack that fails the BMS check at power-on.
• Bench tested on actual hardware: We cycled this pack through the Kronos C3+ power-on sequence and sensor-initialisation load. The BMS held across the inrush spike at probe power-up and maintained voltage above the instrument's cutoff threshold under sustained logging load.
• First-use calibration on the Kronos C3+: After fitting a new pack, run a full calibration cycle through the instrument menu before field deployment. The Kronos C3+ maps battery state during calibration — skipping this step causes premature low-battery warnings during your first measurement session in the field.

BMS cutoff when the Kronos C3+ probe module initialises

When a probe or sensor module powers up, the Kronos C3+ draws a sharp inrush current as the module's internal electronics come online. An aged original pack — or a replacement with weak cells — can sag below the BMS cutoff threshold at that moment, tripping a protective shutdown before the measurement even starts. This is not a firmware issue; it is a cell-level voltage sag event. A fresh pack with intact internal resistance handles the spike without dropping below the 6.0V minimum the instrument monitors.

Pack will not charge or respond after months unused in a carry case

Li-ion cells that self-discharge below roughly 2.5V per cell enter a deep-discharge state where the pack's BMS locks out charging to prevent thermal risk. The Kronos C3+ charger sends a charge request that the BMS ignores entirely, so the indicator light never activates. Some chargers include a recovery or trickle mode — connect the pack, hold the charge button for 10 seconds if your charger supports it, and wait up to 30 minutes for the BMS to re-initialise. If cell voltage has dropped below 2.0V per cell, recovery is not guaranteed.