Technical guides about OCPP, CPO operations, smart charging and e-mobility.
A charge detail record (CDR) is the billing truth of every EV charging session. Learn which fields a CDR contains, how it is built from OCPP data, how credit CDRs work and how to reconcile CDRs with roaming partners without disputes.
Read more →A practical walkthrough of every OCPI 2.2.1 module: Versions, Credentials, Locations, Sessions, CDRs, Tariffs, Tokens, Commands, ChargingProfiles and HubClientInfo, with sender and receiver roles, status codes and common integration pitfalls.
Read more →Roaming hubs connect hundreds of charging networks and e-mobility providers through one integration. Learn how hubs work, what they cost, how they compare with peer-to-peer OCPI and how to choose a roaming strategy.
Read more →Should you install an 11 kW or a 22 kW wallbox? Compare charging speed, which cars benefit, installation and grid requirements, costs and load management, with clear recommendations for homes, workplaces, hotels and public sites.
Read more →Single-phase or three-phase charging? How phases determine charging power (3.7, 7.4, 11 and 22 kW), why the car's on-board charger matters, phase imbalance rules, phase rotation for load balancing and what it means for site planning.
Read more →Why does a car charge at 150 kW one minute and 40 kW the next? The charging curve explained: constant current and constant voltage, state of charge, temperature, peak vs average power, and what the curve means for charge point operators.
Read more →How long does an EV take to charge? A simple formula, charging time tables for AC and DC chargers and common battery sizes, and the factors that make real sessions faster or slower, from on-board chargers to cold weather.
Read more →kW and kWh are the two numbers behind every charging session, and mixing them up causes confusion about speed, battery size and price. A clear explanation with examples, formulas and how both appear in OCPP meter data.
Read more →IEC 61851 defines four charging modes, from a household socket to DC fast charging, and the control pilot signal that lets car and charger agree on current. Learn the modes, pilot states A to F, PWM current signalling and how it all appears in OCPP.
Read more →GB/T is China's national EV charging standard and one of the most widely used in the world. Learn how its AC and DC connectors work, how communication differs from CCS, what ChaoJi is, and when operators outside China need GB/T.
Read more →NACS, standardised as SAE J3400, is becoming the main charging connector in North America. Learn its history, technical ratings, how it relates to CCS1 and ISO 15118, adapters, and what charge point operators should install.
Read more →CCS and CHAdeMO are the two classic DC fast-charging standards. Compare connector design, communication, power, vehicle support and bidirectional charging, and decide whether your new chargers still need a CHAdeMO cable.
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