Resistors in charging cables

The AC charger cables have a resistor between protective earth (PE) and the proximity pin (PP) pin to indicate

  • that the plug is inserted
  • that the plug can therefore be locked (type 2 only)
  • the gauge of the cable, and thus the maximum current

Note that the PP pins are NOT wired through the cable. The most common resistor values and also those of your standard Renault cable are 220 ohms, corresponding to 6 mm2 and 32 amps continuous, and 680 ohm, corresponding to 2.5 mm2 and 20 amps continuous. These are per strand values and the power varies given the number of phases used.

These PP-PE resistors should be installed on both ends of the cable, which I had not realized before. Yesterday I helped a friend changing his home charger from a socket type to a fixed cable type, so that he didn’t have to get the cable from the trunk every evening. The cable came pre-wired with the resistor in the plug, but it didn’t work. Only when we installed a PP-PE resistor in the charger itself, indicating the cable was inserted on that end, the charger started the process. The other side effect is that if you measure the connectivity between the PP pins on your standard Renault cable, you’ll measure a confusing 440 ohms. That’s because both ends are wired to the ground lead with 220 ohm resistors.

Posted in Hardware
4 comments on “Resistors in charging cables
  1. Borut says:

    I will put additional resistor of 460 Ohm with switch in serial with existing one, in to charging cable for manual selection of cable type. Must I put it on the car’s side or on the charger port’s side for maximal power selection (32 or 20 A)?

  2. Jeroen Meijer says:

    Either one should do. If you put it car side, the car will throttle. If you put it charger side, the charger should not set it’s PMW signal above said current, and the car should adhere to that too. Cool mod.

  3. Borut says:

    I install a small button on the charger’s side of the type2 cable for changing a resistor value between 220E and 680E.
    Now I can select between 21.6kW and 9.3 kW charging power at 22 kW charger. The 1500E resistor didn’t work.
    here are some photos
    http://evsvet.eu/viewtopic.php?f=11&t=486&start=184

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