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DC barrel (coaxial) charge connector (5.5 x 2.1 or 5.5 x 2.5 mm): pinout, rating and use
What the DC barrel (coaxial) charge connector carries, how it is rated, and which e-bike systems use it.
Power panel
Voltage
common on 36 V to 54.6 V charge outputs
Connector data
| Pins / contacts | 2 conductors: centre pin and outer barrel, no data pin |
|---|---|
| Current rating | typically up to about 5 A, best for lower-power packs |
| Voltage range | common on 36 V to 54.6 V charge outputs |
| Locking | non-locking, friction fit |
| Common uses | budget and mid-range e-bikes, scooters and many hub-motor packs |
Common uses: budget and mid-range e-bikes, scooters and many hub-motor packs.
The DC barrel is the cheap, compact plug: a 5.5 mm outer with a 2.1 mm or 2.5 mm inner pin. It carries no data pin, so it cannot signal temperature to the BMS. The trap is polarity: centre-positive versus centre-negative are not interchangeable and a mismatch can spark or damage the pack.
Systems and other connectors
XLR 3-pin charge connector3-pin locking, up to 16 ARosenberger / Magcode magnetic charge connectormagnetic snap, keyed
Sources: ebikes.ca, E-bike Connectors reference ยท Cyberpika, Connector Types Explained: DC Barrel, XLR, Rosenberger