Home charging cable does not lock. Normal?

[Hay]

I recently bought an MG4 and am loving it. Sofar I've only charged it with the standard slow home charger, which works fine, but I've noticed that it doesn't actually lock the plug in place. It's charging fine, but I can pull the plug out any time. Is the locking thing just for public/ fast charging or is something wrong with either my car or the plug?

 

[DixieTGS]

Assuming you're talking about the plug in to the car, that doesn't seem right.

From memory I think I get the charging port lights as follows:
Light blue: Plug the cable in to the car.
Dark blue: (and various clicks): The car is talking to the charger. Unable to remove the plug.
Green: Charging. Unable to remove the plug. One quadrant pulses to indicate state of Charge. E.g. 2 solid one pulsing is 50-75% full.
White finished or paused. Can't remember if you can remove the plug or not. You may need to unlock and colour may change ??

I believe these colours have changed recently with various updates.

 

[Hay]

Assuming you're talking about the plug in to the car, that doesn't seem right.

From memory I think I get the charging port lights as follows:
Light blue: Plug the cable in to the car.
Dark blue: (and various clicks): The car is talking to the charger. Unable to remove the plug.
Green: Charging. Unable to remove the plug. One quadrant pulses to indicate state of Charge. E.g. 2 solid one pulsing is 50-75% full.
White finished or paused. Can't remember if you can remove the plug or not. You may need to unlock and colour may change ??

I believe these colours have changed recently with various updates.

Thanks, good to know. It goes through those colours as you describe, but even when green (charging) I can remove the charger plug from the car, easily (no resistance at all). I've tried with the car itself locked and unlocked, no difference.

I need to bring it in to the dealer anyway for something unrelated, sounds like I should ask them to take a look at this. Not a massive problem when charging at home but if i want to use a public charger this might be an issue.

 

[Rolfe]

Definitely something wrong. Are you locking the car?

The morning after I bought mine I had to make an embarrassing noob call to the dealer. "How do I get the car to let go of the charging plug?" Reply, in world weary tones, "unlock your car."

 

[Hay]

Definitely something wrong. Are you locking the car?

The morning after I bought mine I had to make an embarrassing noob call to the dealer. "How do I get the car to let go of the charging plug?" Reply, in world weary tones, "unlock your car."

Yep, am locking the car. I will have to think of another embarrassing noob question I guess ?

 

[decrep]

I'm a bit worried about removing cable while charging. Even on the home charger mine is delivering 1.7kW just breaking that circuit could make a big arc, this will erode the contacts creating a higher resistance than normal. Things could get hot or just stop working. I think the lock in feature isn't just there for public chargers.

 

[Coulomb]

Even on the home charger mine is delivering 1.7kW just breaking that circuit could make a big arc,

Especially as there is a large inductor involved. Hopefully the OP was saying that it would theoretically be possible to remove, not that they would actually do this while charging.

This certainly needs fixing.

 

[Hay]

Especially as there is a large inductor involved. Hopefully the OP was saying that it would theoretically be possible to remove, not that they would actually do this while charging.

This certainly needs fixing.

Thanks for the heads up - and yes, definitely not intending to do this, it's just less of a concern at home because no strangers will drop by to try and take it out.

 

[richev]

Does the car stop the charger when you unlock? If you stand next to the charging port when cable is plugged in and when it is not does it sound like it attempts to lock/unlock the handle if the cable is there as you lock and unlock the car?

Odd are the car must think it is locked to start the charge, so some of the mechanism might be missing.

 

[Rip Van]

Especially as there is a large inductor involved. Hopefully the OP was saying that it would theoretically be possible to remove, not that they would actually do this while charging.

This certainly needs fixing.

Surely the pin arrangement in the plug will drop the control circuit before the power.
Large three phase plugs had a shorter pilot pin in case a plug was drawn out with the power still on, fifty years ago!
Still needs sorted though.

 

[Torryhun]

think the lock in feature isn't just there for public chargers.

All plugs ,be it at home or public should lock in place when the car is locked ?

 

[Coulomb]

Surely the pin arrangement in the plug will drop the control circuit before the power.

Yes, that's true. If the plug is yanked out quickly, I wonder if there would be enough time to ramp the power down before the power conductors let go.

 

[Rip Van]

Yes, that's true. If the plug is yanked out quickly, I wonder if there would be enough time to ramp the power down before the power conductors let go.

Yep, some of the plugs I'm talking about were withdrawn, most of the way, on a screw. They were also too heavy to move quickly.

 

[MuzGB1970]

Does the car stop the charger when you unlock? If you stand next to the charging port when cable is plugged in and when it is not does it sound like it attempts to lock/unlock the handle if the cable is there as you lock and unlock the car?

Odd as the car must think it is locked to start the charge, so some of the mechanism might be missing.

The car does not need to be locked to start a charge, it starts once it has handshaked with the charger. The cable lock should engage once charging commences whether the car is locked or not.

 

[siteguru]

There's a manual mechanism to release a locked-in plug. (Access via a hatch in the boot). I wonder whether that's stuck in the unlocked position?

 

[Kithmo]

Do you have another 7kW AC cable to check if that one doesn't lock in as well, you'll probably have to lock the car to test this.
If neither lock in place then it's the car, if the separate cable locks in then it's the granny plug.
If it's the car check the release cable as @siteguru says above.
If it's the granny plug check the little square hole on the plug has not broken and turned into a square slot.

 

[kiwi]

Unlike DC circuits, you don’t get big arcs on AC circuits. If you did, the US would be in big trouble because their 15A (1.7kW) home outlets don’t have switches. On AC the current falls to zero every half cycle of the mains frequency hence any arc is usually extinguished.

Home EV charging uses AC via the pins on the round part of the CCS plug. Fast charging uses DC via the two extra pins below the round part of the plug that are normally covered with a rubber cap on the MG4. In both cases there are dedicated pins in the round part of the plug for control.

Having said that, on the MG4 the plug should auto lock while charging on AC or DC.

I think (but don’t quote me) that the plug isn’t locked for AC charging on the MG ZS.

 

[Coulomb]

Unlike DC circuits, you don’t get big arcs on AC circuits.

At very high voltages, the arc is so hot that the zero crossings aren't enough to extinguish the arc. I've seen an AC arc last about 2 seconds after hundreds of millimetres of separation (on video, not real life, thankfully). But yes at mains voltage, it's much less of a problem with AC than DC, granted. But a half cycle of AC (10ms) is still plenty of time to poke holes in an IGBT's insulation.

I think (but don’t quote me) that the plug isn’t locked for AC charging on the MG ZS.

My Mark 1 ZS certainly locks the charge port when AC charging, and I see no reason for that to change with later models.

 

[Anon70]

That sounds wrong, this is from the owners manual and it even tells you how to manually unlock the connector in the event the electronic lock fails to unlock

 

[kiwi]

My wife drives a ZS EV and I’m pretty certain you can pull the plug while it’s charging on AC as we routinely share the same AC granny lead. Maybe she has a fault. You definitely can’t pull the plug on DC.

As for the AC voltage and arc, sure on high voltages there are second order effects, but for home domestic AC 230/415V self extinguishing is normal unless the gap is smaller than the breakdown for air.