5 Critical Tests to Perform After Commissioning an Electric Vehicle Charging Station

When installing a new electric vehicle charging station — whether AC or DC fast charging — commissioning is only complete when critical tests verify the station is safe, operational, and ready for public or fleet use. Many teams simply connect a vehicle to check for charging, but this approach alone does not expose underlying faults and lacks repeatability.

Here are five essential tests every technician or operator should perform after commissioning Electric Vehicle Supply Equipment (EVSE) to ensure performance, interoperability, and most importantly — safety.

1. Control Pilot (CP) Signal Testing

The Control Pilot (CP) signal enables communication between the electric vehicle and the charger. It tells the vehicle if it is safe to draw current and how much it should draw.

Importance:

A faulty CP signal can prevent charging or cause unsafe power delivery. Testing ensures the station will operate reliably with all vehicle types.

Key Indicators:

• Voltage levels (typically ±12 V to ±9 V depending on the charging state)
• Pulse Width Modulation (PWM) signal duty cycle
• Relay control behavior

Note: Fluke FEV100 or FEV150 tools can simulate and measure CP signals without an electric vehicle on site, ensuring repeatable and consistent tests across installations.

2. Insulation Resistance Testing

High-voltage DC fast chargers pose serious electrical hazards if the insulation between conductors and ground is compromised.

Importance:

Poor insulation can cause arcing, tripped breakers, or shock hazards. It is also a required test for compliance with safety standards, such as UL 2202, Standard for Electric Vehicle Charging System Equipment, and NEC 625, Electric Vehicle Power Transfer System.

Key Indicators:

• Minimum resistance values (typically 1 MΩ or greater at 500–1000 V)
• Insulation degradation over time

This test should be done before energizing the station, especially with new wiring and connectors.

3. Ground Fault Protection Verification

Electric vehicle chargers must detect leakage currents to protect users from shock in case of insulation failure.

Importance:

A failure in ground-fault detection circuitry could go unnoticed without deliberate testing — leaving the system vulnerable and unsafe.

Key Indicators:

• Functional ground-fault interrupt response
• Accurate tripping threshold (typically 20–30 mA)

Simulating ground faults with a testing tool confirms the protective circuitry of the charger is operating correctly.

4. Load Simulation and Voltage Drop Measurement

Without load simulation, confirming that the station can deliver the correct voltage and current during real-world use is impossible.

Importance:

Issues like undervoltage or voltage drop can cause slow charging, failed sessions, or damage to electric vehicle batteries.

Key Indicators:

• Voltage levels under load (verify adherence to specifications)
• Ripple or harmonics in output current
• Cable heating or connection resistance

This is especially important for DC fast chargers, where higher currents amplify minor wiring issues.

5. Connectivity and Network Function Test

Modern EVSE is often networked for billing, monitoring, and remote diagnostics. Verifying cloud or Open Charge Point Protocol (OCPP) connectivity is frequently skipped during final walk-throughs.

Importance:

Without network connectivity, the station may appear unavailable, fail to report faults, or may not charge at all in pay-per-use scenarios.

Key Indicators:

• Successful cloud handshake
• OCPP messaging logs
• Firmware updates and remote reboot functionality

Testing should also confirm whether Radio Frequency Identification (RFID) readers, connected applications, or Near Field Communication (NFC) systems operate correctly.

Achieving Reliable Commissioning

Commissioning an electric vehicle charger is not just about turning it on. It is about verifying every component, from ground integrity to communication protocols. These five tests are fundamental to a safe, interoperable, and reliable EVSE deployment — whether you are managing a large-scale charging network or servicing a single fleet depot.

Fluke FEV100 and FEV150 tools facilitate load simulation, signal testing, and results documentation without requiring an electric vehicle on site.