About this replacement
Dranetz HDPQ-SP-Xplorer400 — 9.6V Ni-MH Replacement Battery (BP-HDPQ-SP)
This is a 9.6V, 700mAh Ni-MH replacement battery for the Dranetz HDPQ-SP series power quality analyzers. It fits the HDPQ-SP-Xplorer400, HDPQ-SP-Xplorer, HDPQ-SP-Guide, and HDPQ-SP-Visa. The OEM part number is BP-HDPQ-SP.
- HDPQ-SP series compatibility: The Xplorer400, Xplorer, Guide, and Visa all share the same 9.6V battery rail, connector format, and BMS handshake protocol. One pack covers the full platform.
- Bench tested on actual hardware: We cycled this pack through full charge and discharge on the HDPQ-SP platform. The BMS accepted the pack without error flags, and voltage held steady under the sustained draw of active probe modules and live logging.
- Post-install calibration cycle: After fitting this battery, run a full calibration cycle through the instrument menu before field deployment. The HDPQ-SP maps battery state during calibration — skipping this step causes premature low-battery warnings on the first measurement session, even with a fully charged pack.
BMS lockout after the HDPQ-SP sat unused in a carry case for months
Ni-MH cells self-discharge during storage. If an HDPQ-SP sits unused long enough, the pack voltage drops below the BMS recovery threshold and the instrument will not power on or accept a charge. This is a protection state, not a failed cell. Connect the charger and leave it for at least 4–6 hours without interrupting the cycle — most BMS controllers on this platform will recover the pack once voltage climbs back above approximately 8.4V. Do not power-cycle the instrument during this recovery charge.
Readings resetting or drifting mid-logging session
This is not a software fault. When the HDPQ-SP runs multiple probe modules simultaneously during a long logging session, the sustained current draw can pull cell voltage low enough to trigger a momentary BMS dropout. The instrument loses power briefly, resets its logging state, and resumes — making it look like a firmware or sensor glitch. The fix is to verify the replacement pack is fully charged before deployment and to confirm cell voltage reads above 9.2V at the battery contacts before starting a long session. A pack with even moderate capacity fade will drop out under this combined load before the display shows a low-battery warning.