Owon Powers PDS Oscilloscope 7.4V Replacement Battery 540-337

Owon PDS5022 / PDS602 Series — 7.4V Li-ion Replacement Battery (540-337)

This 7.4V, 10200mAh (75.48Wh) lithium-ion battery replaces the OEM pack in Owon PDS-series portable digital oscilloscopes, including the PDS5022, PDS602, and HC-PDS. It fits the same connector footprint and communicates with the onboard BMS using the same charge-state handshake as the factory cell. Use it anywhere AC power is unavailable — field diagnostics, panel testing, or bench work away from a mains outlet.

• PDS-series platform fit: The PDS5022, PDS602, and HC-PDS share a common 7.4V power rail and identical battery bay geometry. The 540-337 part number covers all three — the instrument's charge controller negotiates with the same BMS logic across the series, so one cell revision fits the full group without modification.
• Bench tested on actual hardware: We ran this pack through charge and discharge cycles on a PDS-series unit, monitoring BMS cutoff thresholds and charge-acceptance response. The protection circuit held cutoff at the expected low-voltage threshold and accepted charge current without triggering fault flags.
• Post-install calibration step: After fitting this battery, run a full calibration cycle from the oscilloscope's system menu before field deployment. The instrument maps battery state during calibration — skipping this causes premature low-battery warnings to appear during your first measurement session even when the pack is well above depletion.

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

Lithium-ion cells left in storage self-discharge slowly. If the pack drops below approximately 2.5V per cell (5.0V total for a 2S configuration), the BMS trips into a protective sleep state and blocks both charge input and load output. The oscilloscope will appear completely dead — no display, no response to the power button. To recover the pack, apply a low-current "wake" charge using a compatible charger capable of trickle or pre-charge mode; hold it at that rate until cell voltage climbs above 3.0V per cell, then allow normal charge to complete.

PDS oscilloscope shutting down mid-measurement with no low-battery warning

This happens when sustained probe load — especially with active probes drawing power from the oscilloscope's probe port — pulls enough current to sag cell voltage below the BMS cutoff threshold momentarily. The BMS reads this as a fault and cuts output before the low-battery indicator has time to display. Check that active probe power settings are not set above the probe's rated draw in the instrument menu. If shutdowns persist, allow the pack to charge to full and verify the charge termination voltage reaches 8.4V before use.