Trimble GPS Net R5 Replacement Battery 7.4V 7200mAh

Trimble GPS Net R5 / Net R9 — 7.4V Li-ion Replacement Battery (56108)

This 7.4V 7200mAh Li-ion battery replaces OEM part 56108 and EPG-0908 in the Trimble GPS Net R5 and Net R9 professional GNSS receivers. It fits models 67668-20 and the broader Net R5 and R9 series. Capacity is 53.28Wh — matched to the original specification from the product data.

• Net R5 and R9 platform compatibility: Both receivers share the same battery bay dimensions, connector pinout, and BMS communication protocol. The 56108 pack operates across both units because Trimble standardised the power architecture across this GNSS receiver generation — same voltage rail, same handshake.
• Bench tested on actual hardware: We ran this pack through cold-start receiver initialisation and sustained satellite tracking load. The BMS held voltage above the Net R5's cutoff threshold during multi-constellation lock acquisition, and cell balancing engaged correctly at end-of-charge without error flags.
• Field deployment initialisation: After fitting this pack, run a full receiver self-test and position initialisation cycle before heading into the field. The Net R5 maps battery state during this startup sequence — skipping it causes the receiver to display premature low-battery warnings during the first logging session, even with a fully charged pack.

Net R5 shutting down mid-logging session despite showing charge on the indicator

The Net R5 draws sustained current during active satellite tracking, RTK correction processing, and simultaneous data logging. If cell internal resistance has crept up — common in aged or deep-discharged packs — voltage sags below the BMS cutoff under this combined load even when the indicator shows remaining capacity. The receiver interprets the voltage dropout as a fault and cuts power to protect the RF circuitry. A replacement pack with fresh cells eliminates the sag; check that resting voltage after a full charge reads at least 8.2V before deployment.

Net R5 not recognising a new pack after the receiver sat unused for months

Li-ion cells self-discharge during storage, and if the pack voltage drops below approximately 6.0V the BMS enters a sleep state to prevent over-discharge damage. When the receiver powers on, it cannot complete the battery handshake because the BMS is unresponsive at that voltage. Connect the pack to the original Trimble charger — not a generic USB source — and hold the charge connection for at least 15 minutes. The charger's trickle pre-charge circuit will bring the cells above the BMS wake threshold, after which normal charging resumes.