Testing an EV charger or a grid-tied inverter for production release isn't a single measurement — it's a sequence covering electrical performance, communication protocol compliance, and safety, often against several regional standards at once. Running that sequence manually, station by station, doesn't scale to production volumes. Preen's ATS platform — covering EVSE ATS for EV charging equipment and a related Smart Inverter ATS for grid-tied inverters — automates it.
EVSE ATS: Testing AC/DC EV Chargers
The EVSE (Electric Vehicle Supply Equipment) Automated Test System is built to test both AC and DC EV chargers against the standards that actually govern them: SAE J1772, CNS 15511, the NB/T 33001, 33002, 33008.1, and 33008.2 family, GB/T 18487.1, GB/T 27930, and the broader set of EV interoperability test specifications a charger has to satisfy before it can ship into a given market.
The system provides both electrical performance testing and communication protocol testing in one platform, and critically, it can simulate a charger's output and communication signals to test for EMI interference with the control signal itself — a failure mode that's easy to miss if electrical and communications testing are run as separate, disconnected procedures. It also verifies control-pilot (CP) signal protection response, and runs touch current and insulation testing, the safety checks a charger has to pass before it's cleared for connection to a vehicle.
Smart Inverter ATS: Testing Grid-Tied PV Inverters
The Smart Inverter ATS covers a different device under test — PV inverters — at DC input voltages up to 2000Vdc and grid-tied output voltages up to 600V (line-to-line). Rather than testing electrical performance and communications as separate procedures, it runs the full sequence of grid compliance tests an inverter has to pass, automated end to end.
| Test Type | What It Verifies |
|---|---|
| Slow/Fast Over & Under Voltage | Response to voltage excursions at different rates |
| Over & Under Frequency | Response to grid frequency deviation |
| Synchronization | Correct reconnection to the grid waveform |
| DC Injection | DC component leakage onto the AC grid |
| Unintentional Islanding | Correct disconnection when isolated from the grid |
| Open Phase | Response to a lost grid phase |
| Reconnect | Behaviour restoring service after a fault clears |
| Harmonics | Output waveform quality under load |
In total the Smart Inverter ATS covers twelve distinct test types across these categories — enough to build a complete grid-compliance test report from a single automated sequence rather than assembling results from several separate instruments and procedures.
Combining ATS with a Power Source
Neither ATS platform works in isolation — each needs a power source or grid simulator behind it to actually supply or absorb power during the test sequence. The EVSE ATS is commonly combined with an AFV+ series programmable AC source or a PAS series regenerative grid simulator as the power stage, depending on whether the charger under test is drawing AC or DC power and whether energy needs to be recovered during the test. The Smart Inverter ATS pairs naturally with the same PAS/PFV grid simulator family on the AC side and a DC source such as the ADG+ series emulating the PV array feeding the inverter under test.
Configurable Test Software
Both platforms run on an open, flexible software layer rather than a fixed, vendor-locked test sequence. Customers can configure test criteria to match specific regional standards, internal engineering limits tighter than the regulatory minimum, or a custom sequence built around a particular product's known risk areas. That flexibility matters for manufacturers shipping into multiple regional markets from the same production line, where the pass/fail criteria — and sometimes the test sequence itself — differ from one destination market to the next.