Megger AB2584 TDR2000-C Replacement Battery 9.6V 2000mAh

Megger TDR2000-C — 9.6V Ni-MH Replacement Battery (AB2584 GP)

This is a 9.6V 2000mAh Ni-MH replacement battery for the Megger TDR2000-C and TDR2000/2P Time Domain Reflectometer. The TDR2000-C is a professional cable fault locator used in telecoms and electrical survey work. It sends electromagnetic pulses down a cable and maps reflections to pinpoint faults — a task that demands consistent voltage throughout the session.

• TDR2000-C and TDR2000/2P fit: Both instruments share the same battery bay format, connector pinout, and 9.6V operating rail. The BMS handshake on each unit reads cell count and voltage threshold identically, so a single pack covers both without modification.
• Bench tested on actual hardware: We cycled this pack through the TDR2000-C's pulse-transmit and receive sequence under sustained load. The BMS maintained rail voltage above the instrument's cutoff threshold across repeated measurement cycles without tripping.
• Post-install calibration cycle: After fitting this battery, run a full calibration cycle through the TDR2000-C instrument menu before heading into the field. The instrument maps battery state during calibration — skip this step and the first measurement session will throw premature low-battery warnings that interrupt readings.

BMS lockout after the TDR2000-C sat unused in a carry case for months

Ni-MH packs self-discharge at roughly 1–2% per day. After several months in a case, cell voltage drops below the BMS recovery threshold, and the pack enters a protective lockout state. The instrument may show no charge activity even when connected to a working charger. To recover the pack, apply a slow trickle charge at 0.1C (200mA) for two to four hours before attempting a normal charge cycle — this brings cell voltage back above the 1.0V-per-cell floor the BMS requires to re-initialise.

TDR2000-C shuts down mid-measurement with no prior low-battery warning

This happens when the pulse transmit circuit draws a brief high-current spike that pulls rail voltage below the BMS cutoff threshold — even if the battery indicator looked healthy seconds before. An aged or partially degraded cell has higher internal resistance, so the voltage sag under that spike is steeper than a fresh pack. This is not a firmware fault. Replace the battery and confirm resting voltage reads at least 10.2V (1.275V per cell) before the next session.