After an hour of 'Maximum Amperage' charging mode (charging from 70%) - Got the FLIR camera out and wanted to check to make sure my wiring was up to the task of the full capacity of the charger in the car. Max temp found wasn't above 80F (27C) and even though my sub-panel is 250ft away from my main panel, I only measured a 20VAC drop at full load. Overall, I'm quite pleased. Word to the wise, make sure everything you have is up to the task of a sustained 32A @ 240VAC before you select that 'Maximum' mode in your car. (all FLIR images captured at 46F (8C) ambient temperature. EVSE (I suspect the 'hot spot' is the contactor coil being energized and no real resistance inside the box): Car (had been sitting for over an hour after a 30mi trip and was curious as to what the hot spots would be): Main Panel (50A Breaker and 6AWG line headed out of panel are hot spots):
I put my SE on charge for the first time on Tuesday evening. Although I had set the car for maximum current and the charger dialled up to 32A, the Wallbox app showed the car was only pulling 1/2 power (around 3.7 Kw). The Wallbox did have a software update pending so I've done that but when I checked the Mini owners manual last night I was dismayed to read that maximum current for AC charging is 16A!!! Am I missing something because other online sources show the Mini should handle 32A / 7.4 Kw for 1 phase AC charging. Any advice?
Thanks for this info and pics and the notations for temps. Sounds all good. BTW: I'm using a Clipper Creek evse. They recommend that when charging, if you have some of the cord wrapped around the evse (as for storage when not charging - in other words you don't have the full 25ft of cord extended from the evse to the charging port) you should make the unused footage wrapped on the evase hang loosely to avoid heat building up in the cord. This I think would be so for any mfg's cord.
Here's some evidence to the contrary. I have two Tesla connectors (they are properly called connectors, as they deliver metered AC power to the cars' internal chargers, which convert the AC to DC and send it to the big battery), wired in parallel to a 60A circuit, both dialed to a max of 48A. When I have just my Tesla Model 3 on one of the connectors, it pulls the whole 48 Amps. When I connect the MINI to my second connector, the two connectors talk to each other via a communication cable and share the available 48 Amps between the two vehicles. On my Tesla, I can see the power reading, and it shows a drop from 48A to 24A, exactly half. So, it appears the MINI is drawing and can draw at least 24A. In time, I'll have a chance to watch the two connectors share the load as the Tesla reaches its end of charge cycle and tapers its draw. As the Tesla eases off, the MINI should ramp up to 32 Amps. I'll report when I see it. Perhaps people with "smart" connectors can see the actual output of their systems.
True for any electrical cord... there are many fascinating stories of people using coiled extension cords on a reel and them getting quite hot/catching fire after melting.
What was your state of charge when you plugged in? I ask, because I have observed a 'ramp-down' when mine gets at and above 95% where it rapidly falls off the peak 32A draw and settles down to a 7-10A draw by 98% and almost nothing by 100%.
To expand on your explanation for the uninitiated... this is true of all rechargeables. For instance, Tesla road trip charging strategy is to work the bottom end of your battery while going cross country, to take advantage of the Superchargers' 150kW capacity to dump huge amounts of power into an empty battery. You charge from, say, 5% to whatever you need to get to the next Supercharger, to maybe 60 or 70%. By doing this, you never reach the taper that begins at 80% or so, and so spend only 20 minutes at the Supercharger, instead of the hour and a half it would take to get that last 20%.
In North America with our J1772 plug we only have 1-phase AC support, and with Level 1 charging the vehicle will max out at 15A (but the provided cable only supports 10A). But Level 2 (still 1-phase) will go to 32A, which I do see. I've seen close to 50A with DC Fast charging. Oddly, though, the Owner's Manual says max Level 2 is 16A. Maybe in the UK you do only get 16A on 1-phase, since the Mennekes plug I believe you have supports 3-phase and that's where you'd get higher charge rate?
Hi Puppethead, the Wallbox is promoted as having 7.4Kw output with our standard 1 phase AC. The app allows me to dial in the current up to the 32A max. Methinks I'll need to have a chat with the dealer.
Agreed, sounds like there may be something not quite right... as it sounds like you have everything you need to support the full load.
Another thing to check is try charging at a public charge point. I've found from my experience that not all EVSEs are reliable. While it sounds like everything is right at your home, I'm of the mind that trying a different location would help you identify if it is the vehicle or something else. If you get the same behavior somewhere else then the problem must be the SE.
I don't think this actually proves what you claim it does. I don't think the shared EVSE is that smart. I think it just splits the available power in twain when two vehicles are connected. Even if one of them only pulls 16A, they will both be offered up to 24A.
Hmm, interesting theory; you may be right. I guess the way to test it would be to charge my SE until it is well on the taper with, say, half an hour until it finishes charging, and then I'll plug in a well-discharged Tesla that would normally pull 48 Amps. If it only pulls 24, then we know.
Fun observation from my little corner of fun: No matter what 'maximum amperage' setting I choose in the car (low, reduced, or max), it always charges at the full 32A that my EVSE allows... so... that could be awkward if my wiring wasn't prepared
I think the owner's manual reference to 16 amps is specifically about the level 2 cable that used to be supplied with the car. Its not about the cars ability to charge above 16 amps. Indeed, to reach the 7.4 kilowatt hour charging advertised at 240 volts, you'd have to be around 30 amps. Which is consistent with a 32 amp charger and people's experience charging around 30 amps. It also results in a full charge in about 4 hours which is what's advertised. BTW, to get to those highest levels of charging you have to use the My Mini menu to change from the lower charging rates that the Mini SE defaults to.
I think you might be selecting from the 120V charging options. I was confused by that at first as well. There are only two options for 240V, Reduced (3kW) and Maximum (7kW)
