Fluke 700 Calibrator Replacement Battery 7.2V 2500mAh

Fluke 700 / 740 / 744 Calibrator Series — 7.2V Ni-MH Replacement Battery (BP7235)

This is a 7.2V 2500mAh Ni-MH replacement battery for the Fluke 700, 740, and 744 Calibrator series, along with the DSP-100 and compatible models. It slots into the battery compartment and powers the calibrator during portable field use and bench work. The OEM part numbers this pack replaces are 116-066, 668225, and BP7235.

• Calibrator series compatibility: The 700, 740, and 744 Calibrators share the same battery bay dimensions, 7.2V rail, and connector pinout. One pack covers the full lineup without modification.
• Bench tested on actual hardware: We cycled this pack through charge and discharge on calibrator-class load profiles. The BMS handled the initialisation current spike at instrument power-up without tripping, and held voltage steady under sustained sensor drive.
• Post-install calibration cycle: After fitting this pack, run a full calibration cycle through the instrument menu before field deployment. The Fluke 700 series maps battery state during that cycle — skipping it causes the instrument to throw premature low-battery warnings on the first measurement session.

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

Ni-MH cells self-discharge over storage. If the pack voltage drops below roughly 5.4V — the BMS sleep threshold — the charger sees the pack as absent and refuses to begin a charge cycle. The instrument also will not power on. To recover it, apply a trickle charge at 100–200mA directly to the pack terminals for 10–15 minutes to push voltage above 6V, then transfer to the standard dock. Once the BMS re-initialises, a normal charge cycle completes without issue.

Readings resetting or logging gaps during a sustained measurement session

This happens when sustained sensor load — multiple loops active, output sourcing running — pulls enough current to cause a brief voltage sag that the instrument interprets as a power fault. It is not a capacity problem; it is a cell impedance issue in aged or cold packs. A freshly charged pack at room temperature handles the combined draw without dropout. If sags persist after a full charge, the pack has degraded beyond recovery and needs replacement.