Reliability Testing of EV Charger Internal Control Wiring in Extreme Cold

Jul 30,2026 Blog

In extremely cold environments, EV charger reliability depends on more than power modules, charging connectors, and thermal management systems. The low-voltage internal control wiring connecting the control panel, sensors, and auxiliary circuits must also perform reliably at low temperatures.

Low temperatures can make control wire insulation brittle. When technicians open the charger for maintenance or repair, the control wires may bend or shift, causing the insulation to crack. In severe cases, insulation under continuous bending stress may crack even without the charger being opened.

Control wire in EV charger XYDF
Control wire in EV charger XYDF

Why Test Internal Control Wiring for Low-Temperature Performance?

Control wire failures are often first reflected in the control system or operating panel. Possible symptoms include:

  • Abnormal temperature or status readings
  • Loss of communication with control modules
  • False triggering of emergency-stop or door-interlock signals
  • Incorrect charging-status information or unexpected charging interruptions

These symptoms can also be caused by sensors, connectors, or control modules. Intermittent control wire faults can therefore be difficult to identify and, in severe cases, may create safety risks.

Control Cable Cracking in Extreme Cold
Control Cable Cracking in Extreme Cold

Reliability Testing of XYDF EV Charger Internal Control Wiring

XYDF uses FLRY-B automotive-grade wire that complies with ISO 19642-3:2019. These control wires are used for control, signal, and auxiliary circuits inside the charger and do not carry the main charging power.

TestTest ConditionsResultRisk Evaluated
Low-temperature bendingStored at −40°C for 4 hours, loaded with 0.5 kg, wound for three turns at 5D, followed by a 1 kV withstand-voltage testNo cracking or breakdownBrittle insulation during low-temperature maintenance or assembly
Low-temperature impactStored at −15°C for 16 hours, then impacted by a 100 g weight dropped from 100 mmNo cracking or breakdownInsulation damage caused by impact at low temperatures
Low-temperature bending after agingAged at 125°C for 240 hours, followed by bending at −25°CNo cracking or breakdownLoss of low-temperature flexibility after long-term aging
Temperature-humidity cycling40 cycles covering −40°C, high humidity at 85°C, and a 100°C stageNo cracking or breakdownInsulation failure caused by temperature and humidity changes
Abrasion testInsulation surface tested for abrasion in accordance with the standard780 mm, compliantWear caused by contact with wire-fixing structures
Scrape abrasion testInsulation surface repeatedly scraped in accordance with the standard1,000 cycles, compliantInsulation wear caused by sheet-metal edges or cable-management structures

The control wire samples showed no cracking or electrical breakdown during the low-temperature bending, low-temperature impact, or post-aging bending tests. The insulation also remained functional after 40 temperature-humidity cycles.

Internal control wiring inside an XYDF EV charger
Control wire in an XYDF EV charger

The test results show that the automotive-grade internal control wiring used by XYDF can help improve EV charger stability in extremely cold environments.

Extreme-Cold EV Charging

Reliable Internal Wiring Is Only One Part of Extreme-Cold EV Charging

Explore XYDF’s complete approach to enclosure protection, temperature control, component selection, condensation prevention, and reliable charger startup in extreme-cold environments.

View the Full Case Study
+86 133 3697 0557
service@xinya-ee.com