A proximity pilot (PP) is a dedicated signaling circuit used in conductive EV charging connectors—most commonly Type 2 (IEC 62196-2) and Type 1/J1772—to indicate the presence of a plug and the charging cable’s current-carrying capability. PP helps ensure the EV and charging station do not exceed the cable’s safe current limit, supporting safe, standards-compliant AC charging.
Why Proximity Pilot Matters in EV Charging
PP is a simple but critical safety feature in everyday charging.
– Prevents the charger from delivering more current than the cable is rated for
– Helps avoid overheating of cables and connector contacts
– Enables correct operation across different cable types and ratings
– Supports safe public and destination charging where users bring their own cables
– Improves interoperability between EVs, cables, and EVSE hardware
How Proximity Pilot Works
PP uses a resistor integrated into the plug/cable assembly to encode a cable rating.
– When the plug is inserted, the PP circuit becomes detectable by the EVSE and/or vehicle
– A defined resistor value corresponds to a specific maximum allowable current
– The charging station uses this signal to cap the available current to the cable’s limit
– On Type 2 connectors, PP is also used to detect plug presence and support safe mechanical handling logic
Proximity Pilot vs Control Pilot
PP and CP are often mentioned together, but they serve different purposes.
– PP (Proximity Pilot): cable/plug presence and cable current rating indication
– CP (Control Pilot): active communication between EV and EVSE for charging control, state signaling, and PWM current request
– PP is primarily a passive identification method, while CP manages the charging session behavior
Where PP Is Used
PP is found in most AC charging connectors and cable assemblies.
– Type 2 charging cables used in Europe for home, workplace, and public AC charging
– Type 1 (J1772) connectors used in North America and some markets
– Tethered cables and user-provided cables where the cable rating must be recognized
– Destination charging sites with mixed vehicles and varied cable types
Practical Examples in Real Installations
– A 32 A-capable charge point must reduce output if a user plugs in a lower-rated cable
– In multi-tenant or workplace sites, PP helps standardize safe charging even when users supply different cables
– PP supports safe upgrades: adding higher-power AC EV chargers still requires respecting the connected cable rating
Limitations and Considerations
– PP indicates cable rating, but does not replace proper temperature monitoring in connector contacts
– Incorrect or counterfeit cables may have wrong resistor coding, creating safety and liability risks
– PP does not provide advanced authorization, billing, or smart charging functions—those depend on backend control and protocols
Related Glossary Terms
– Control Pilot (CP)
– IEC 62196
– IEC 61851
– Type 2 Connector
– J1772 connector
– AC charging
– EVSE
– Cable management