The solution to seamless interoperability: the CharIN CCS Test System

Marc Mültin
Marc Mültin
May 30, 2018
• Updated
min read
The solution to seamless interoperability: the CharIN CCS Test System

The importance of interoperability testing eliminates the need for every EV manufacturer to test its charging solution against every charging station around the world.

When new technology enters the market, we – as a community of experts – need to make sure that each implementation is working according to international specifications. The interoperability of ISO 15118-related charging solutions is key for user acceptance and economies of scale but it also creates a major technical challenge due to vastly different implementations, individual use cases, and requirements across a diverse global market.

This brings me to a term that is considered as the holy grail when it comes to ISO 15118-compliant products: the "golden test device”, officially also known as the "CharIN CCS Test System". CCS stands for Combined Charging System. The goal of such a device is to eliminate the need for every EV manufacturer to test its charging solution with every charging station provider around the world before it can be deemed interoperable. The costs associated with our current system are prohibitive and drastically slow the rate of additional implementations from coming to market.

Consider when you or your company creates a new charging station or produces a new electric car that is supposed to conform to the safety-related IEC 61851 standard and the higher-level communication protocols ISO 15118 or DIN SPEC 70121. The ideal solution is to have one device that can test every aspect of your product to check for compliance with these international standards. This requires test procedures to be available for each and every requirement within these complex and often over-whelming standards. The test specifications for ISO 15118-2, ISO 15118-3, ISO 15118-8 and DIN SPEC 70121 have either already been published as International Standard (IS) or have been initiated, as you can see from the table given below.

Interim solutions on your way to CharIN CCS Test Systems

However, given how recently these conformance test specifications were published, and the fact that we are still missing conformance test specs for AC charging stations (according to IEC 61851-1) and DC charging stations (according to IEC 61851-23), the industry unfortunately does not yet have such a device ready or available.

Here is what we do have:

  1. Testing systems already exist that cover a broad spectrum of the necessary conformance tests, like those from Verisco, Vector, Comemso, and Keysight Technologies. The available test systems differ a little, some are better positioned in the area of communication flow testing, others are currently focusing more on testing the power flow.
  2. RISE V2G is available as the only open-source implementation of ISO 15118 to test your implementation for conformity to this standard.

This is an example of Verisco's portable test system that covers communication flow and power flow test procedures.

Portable VERISCO test case

This next disclosure might be cause for concern: I was recently told that some of the DIN SPEC 70121 charging stations being installed around the world do not perfectly comply with IEC 61851-23. This already requires global EV manufacturers to implement bug fixes for these charging stations, which increases the overall costs in the necessary quest for industry-wide, global interoperability.

Test devices that include all test cases would eliminate this problem. But they are still in the process of being invented and built. While we wait for these devices to become available on a global scale and in a sufficient quantity, we must rely on the aforementioned devices and bi-annual testing symposia hosted by industry organizations.

On the up side, these events offer unparalleled networking along with the opportunity to get to know our ever-growing community of global experts face to face. Eager to get a feeling how these events look like? Then check out my article on "Videos from 8th International CCS & ISO/IEC 15118 Testing Symposium".

Will you be attending the upcoming 10th International ISO 15118 and CCS Testing Symposium on November 15th and 16th in Arnhem, Netherlands? This testing event is for physical EVs and charging stations, as well as communication controllers. Visit for more.

The 9th Symposium will take place on the 11th and 12th of September in Detroit, Michigan. It’s co-located with the 1st CharIN North American CCS and ISO/IEC 15118 Interop Event, which will take place on the 10th of September. There will be a focus on EV and EVSE testing only at this event, meaning there will be no controller tests. While I won’t be able to make it to Detroit, I’ll definitely be at the Anniversary Edition Symposium and I hope to see you there!

Get ready for ISO 15118 conformity with RISE V2G 

If you’d like to explore RISE V2G (GitHub) as an option, it has been extensively tested at each testing symposium, including an intensive penetration test by Verisco’s system (see blog article "Bulletproof ISO 15118 Implementation - RISE V2G Tested by Verisco Test System"). This has made RISE V2G a highly used and appreciated solution by companies and research institutions worldwide.

Want to find out more? Check out this free video course RISE V2G Basics: Revolutionize Electric Vehicle Charging – With Plug & Charge Powered by RISE V2G.

To fully understand RISE V2G and get an in-depth, step-by-step guide to ISO 15118, take a look at RISE V2G Advanced Course I: Master the Communication for Charging Electric Vehicles. Both these courses are perfect preparation for future international testing symposia.

Marc Mültin
Marc, the Founder and CEO of Switch, has over 13 years of experience in the e-mobility space and holds a PhD in Computer Science. He is the leading global expert and co-author of international EV communication standards (ISO 15118 & OCPP 2.0.1) that underpin the Switch platform.
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