Charge Cord without Earth (Ground)

[Leafer]

I just ran an experiment. I am in the EU.

What USA calls "ground" is usually called "earth" here.

I plugged the KIA-supplied 240V charge cord via an adapter with a plastic earthing pin into my regular outlet in the garage. To my surprise no fault light came on, and the car started to charge. ( I unplugged from the car after a minute or so. )

I thought the "EVSE" (in-line device in the charge cord) checks for proper earthing (grounding) before allowing current to flow.

I find this practice (what my EVSE is doing) risky ? Anyone else ?

 

[notfred]

The EVSE actually checks for no earth leakage rather than that there is an earth. It will engage just live and look for current flow, then drop it and engage just neutral and look for current flow, then engage both and monitor that what goes out on live comes back on neutral while the car is charging.

 

[Leafer]

The EVSE actually checks for no earth leakage rather than that there is an earth. It will engage just live and look for current flow, then drop it and engage just neutral and look for current flow, then engage both and monitor that what goes out on live comes back on neutral while the car is charging.

Very interesting. Thank you for this explanation.

I have heard of portable EVSEs (charge cords) which do much more, including the detection of extension cords -- which may cause them to refuse operation.

 

[notfred]

In the case of extension cords I suspect that the detection is of the added resistance by detecting the voltage drop when current is drawn. That's a good thing, an EVSE will draw a lot of current for a long time, if there's resistance then there is heating and that could well end up with a fire.

 

[GizmoEV]

The EVSE actually checks for no earth leakage rather than that there is an earth. It will engage just live and look for current flow, then drop it and engage just neutral and look for current flow, then engage both and monitor that what goes out on live comes back on neutral while the car is charging.

When I tried to charge using my inverter generator both the Kia EVSE and my Panasonic (Leaf) EVSE give a fault code and won't charge. Upon investigation I found that not having the ground pin was what caused the issue. In reality the inverter generator puts out only around 60V (compared to the ground pin) to each "powered" pin at 180 degrees out of phase to provide the 120VAC output. Using my house wiring with a specially wired outlet with no ground connected produced the same results. What I had to do to charge with my generator was create a special plug with high value resistors connecting the two "powered" pins (hot & neutral) to the the ground pin. This satisfied the Panasonic EVSE into working but the Kia EVSE still wouldn't work with my generator.

It is entirely possible that the EU version of the EVSE does a different type of check so doesn't need the ground, or should I say earth, pin connected.