What does charger uptime mean?

Uptime is the share of time a charge point is online, available and delivers energy. At 97%, it may be out for about 11 days a year at most.

Explained in

Charging hardware · Stop 08Why do chargers fail, and how are they maintained?What uptime means and how it is counted, the usual causes of outages, and how remote diagnostics and modular parts keep chargers running.

Uptime sounds simple, but the definition decides the number. In the US federal rules, a charging port is up when hardware and software are online, the port is available or in use, and it delivers energy at the minimum power. Outages caused by the grid, by the vehicle, by scheduled maintenance, vandalism or natural disasters are excluded.

From “What counts as up”, stop 08

Terms

  1. UptimeThe share of time a charger was technically able to charge.
  1. What is the difference between AC and DC charging?With AC, the car's onboard charger converts the current, which limits power, often to 11 or 22 kW. With DC, the charger carries the converter itself and can deliver far more.
  2. Which connector do public chargers in Europe use?AFIR requires at least Type 2 at public AC points and Combo 2 (CCS) at public DC points. One car inlet takes both: Type 2 above, two DC pins below.
  3. Why do fast chargers have such thick cables?A cable is sized for current, and heat grows with the square of it. At the highest currents, a liquid circuit cools cable and connector so the cable stays manageable.
  4. Why do two cars at one charger get less power?Many chargers divide their power modules between two outlets. A car that is fuller asks for less, so the modules move to the other car.
  1. eCFR: 23 CFR 680.116(b), minimum uptime of federally funded charging ports. https://www.ecfr.gov/current/title-23/chapter-I/subchapter-G/part-680/section-680.116. Checked 09 Oct 2026.