comemso’s Easy Chester Ultimate tests charging stations in one mobile system

comemso electronics has introduced Easy Chester Ultimate, a mobile test system for EV charging infrastructure that combines functional testing, charging communication analysis and electrical safety testing in a single unit. The company says it consolidates jobs that previously often needed several separate instruments, different operating concepts and separate documentation processes.

A 10.1-inch touchscreen guides users through each test, and measurements, communication sequences and results are recorded in a configurable PDF report.

The 15.7 kg unit is built for commissioning, maintenance, repair and periodic inspection directly at charging stations.

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Depending on configuration, Easy Chester Ultimate tests AC, DC CCS and CHAdeMO stations across three levels: functional operation, charging communication and electrical safety. On the communication side it checks Control Pilot and Proximity Pilot signaling and PLC communication including SLAC, and analyzes digital charging communication under DIN 70121, ISO 15118-2 and ISO 15118-3. It can also simulate defined faults on the CP, PP and PE lines and verify how a station responds to insulation faults.

Electrical safety testing covers both the grid side and the vehicle-facing interface. Depending on test direction and configuration, it measures protective conductor resistance, insulation resistance, residual voltage, residual current devices, insulation monitoring and loop impedance, alongside voltage and current measurements.

The system supports AC Type 1 and Type 2, CCS Combo 1 and Combo 2, NACS under SAE J3400 and CHAdeMO, depending on configuration, and its protocol coverage includes IEC 61851-1, DIN 70121, ISO 15118-2 and ISO 15118-3.

Easy Chester Ultimate walks the user through four steps: connect to the station and the grid, select the charging standard and test, run the safety, functional and communication checks, then analyze deviations and document the results. Reports export to configurable PDFs and can be emailed from the device. Wireless firmware updates, integrated device checks and optional remote support round out field use.

By combining the three levels, comemso says the system helps users identify whether a deviation originates from the electrical installation, charging communication, protection functions or general charging behavior.

Typical applications include commissioning new charging points, functional checks after maintenance or repair, diagnosing charging and communication problems, verifying electrical protection functions and periodic inspections.

Optional extensions add a Long Duration Unit for longer charging cycles and the analysis of time-dependent faults, and external DC loads for testing at higher charging power over longer periods.

Source: comemso