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Discussion Starter · #1 ·
Any ideas appreciated. Sometimes my home pod point charges at a rate of 6kw per hour. Other times it’s as little as 2 kw per hour. Doesn’t seem any obvious pattern. Is it likely to be

dodgy pod point
Dodgy cable
Limited electric supply if neighbours charging too
Something else

have escalated to pod point support but having waited 10 days they still haven’t come back despite chasing.

Any ideas gratefully received
 

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The charge point can't directly modulate the power itself, as it's just a mains power outlet with a relay instead of a switch. It can change the advertised maximum current to the charger, though, and the charger can then alter the charge rate. However, the Podpoint doesn't have an on-the-fly current advertisement change capability to respond to things like total demand, so that suggests that the charger (which is built in to the car) may be causing the apparent charge power change for some reason unconnected with the charge point.

The charger may try to reduce the charge current for a few reasons. The BMS may be requesting reduced charge current, for battery health reasons, something that it will do normally during the last few percent of a charge. It may also be that the charger is sensing an excessive voltage drop and reducing charge current, but if so it seems likely that it might flag that up. The charger may also throttle back the charge current if it gets a bit hot, although all EVs have some form of thermal management of their chargers. It could be that there is a car setting that reduces the charge current depending on location or time. The fact that there's no pattern tends to rule that out, though.

It's very unlikely to be related to the charge cable, and cannot be a supply limitation unless there is a major problem with the supply to the house, and that would show up in other ways, most probably with lights dimming and some appliances playing up. Most houses have a supply capable of delivering 80 A to 100 A, so 32 A from a charge point isn't really a big deal. What's the car make and model?
 

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Is this reduced charge rate happening when the battery pack state of charge (SoC) is over about 95%, by any chance? Most EVs reduce the charge rate for the last part of a charge, when the battery management system (BMS) is balancing the cell groups that make up the pack.
 

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Discussion Starter · #5 ·
Seems to happen no matter the charge level. That said we haven’t allowed the charge level below 60% as yet. For example we added 27 kw on 26/5 in 264 minutes. On 1/6 30 kw took 862 minutes…
 

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Just to make things easier to understand, when you say you "added 27 kW is 264 minutes", do you really means that you charged at 27 kW or that you added 27 kWh of energy? I'm guessing that you're getting power and energy mixed up, and that may be a part of the issue, perhaps.

A 32 A charge point will typically charge an EV at around 7 kW to 7.5 kW during the bulk charge phase, so will add about 7 to 7.5 kWh of energy in one hour.

Are you charging to 100% SoC each time?

Also, how are you measuring the charge power (in kW) and the charge energy (in kWh)?

The car, or the Podpoint app, may report that the car has been plugged in for hours, but that may not indicate that it's actually been charging for that time. Knowing how you're measuring charge power at any point in time (in kW) would be really useful.
 

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Discussion Starter · #7 ·
Sorry for the confusion. I meant added and I meant KWh. Generally charging to capacity each time. The data is direct from the pod point app. It has energy added duration and start finish time
 

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I think that all you're seeing is the normal tail off in charge current as the charger (in the car) reduces the rate for the balancing phase of the charge. The app is just estimating based on what the BMS is reporting, so nothing to do with the charge point. What would be useful would be to see what the charge power is (in kW), or the charge current (in A). I'm, not familiar with the e-Niro, but most EVs have a way of displaying the charge current or rate. Knowing that during the first phase of the charge would show whether or not the Podpoint is advertising the correct maximum available current to the charger.
 

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Discussion Starter · #12 ·
Don’t think it’s as simple as the tail off. Per the historic rates in the posts above the time to achieve basically the same increase in energy until battery is full are wildly different. By the way many many thanks for trying to help…it’s much appreciated
 

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In that case I think you need to get the actual current being advertised by the charge point confirmed. It could possibly be that the charge point is advertising a very low maximum available current (not impossible, but also not that probable, IMHO), or it could be that the charger is, for some reason, choosing to reduce the charge current for some reason unconnected with the charge point.

The snag is that, without some further diagnostics, it's not going to be easy to determine if the charge point is at fault or the charger has a problem. It's beyond the capability of most electricians/installers to actually measure the advertised maximum current on the Control Pilot line, although it's not at all a hard thing to do, just needs a bit of test gear connected to see whether the Control Pilot duty cycle is around 50% to 53.3% or not. If it is, then the charge point is advertising the correct maximum and the problem is with the charger.

Hopefully, someone with experience of the e-Niro may chip in as to whether or not it has settable limits on charge current. My Tesla Model 3 had this, the charge current could be easily adjusted from either inside the car or via the app. I know that other EVs have similar options, but just don't know if that's something that's easy to set on the e-Niro or not. 2.9 kW is roughly 10 A to 12 A, so way below the 30 A to 32 A that a 7 kW charge point should be advertising.
 

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Discussion Starter · #15 ·
I think you can change the charge current but at the moment it is set to max ! Think I’ll pop to a public charge point tomorrow and see what difference that makes…if it works ok then I’ll bug pod point. If not it’s over to Kia. Many thanks for persevering….I’m learning as we go
 

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Konas & Ioniqs frequently cut the charge rate right down as you unlock them & open the door etc. The car's getting ready in case you're about to yank out the charging lead & set off. The last thing it want to do is suddenly cut charging while going flat out at 32A, so when it sees sudden activity it will ramp down to 6A, = the minimum charging rate allowed. If you decide to unplug at this rate, the loads etc on the electronics, relays etc are far lighter.

I've been confused by my Ioniq saying I'm only charging at 1.2 kW when it's generally going a lot faster. And my final 90->100% SOC charge goes slower & slower as it approaches 100%, so seems to take forever. At that stage the BMS is tuning individual cells & doing god only knows what fiddling around, so I can see this being a rather unpredictable affair, and perhaps varying a lot from supposedly-identical car to car.
 

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The PodPoint app will show the kWh supplied but the time is irrelevant as it will show from when the charge was initiated until the plug was removed. For example, if your charge started at 20:30 and the battery was completely topped up by 23:30 with, say 20kWh, if you only unplug the car the next morning at 08:00, the app will show 20kWh delivered from 20:30 to 08:00. If you are trying to calculate your PodPoint power supply using those stats then you will be wrong in assuming that it took 11.5 hours to deliver 20kWh.

It actually took only 3 hours which is close to the advertised capability of the charger but unless you were monitoring it during that time, you wouldn't know for sure. If you're on Octopus Go or similar with a smart meter where you can check the half-hourly consumption, you should be able to see roughly what power the PodPoint was delivering.

I recently requested a check from PodPoint on the power delivery of my unit. They sent me a clip of the data that they can access and it showed it delivering at 30Amp but my charge eventually dropped but that was because the BMS started to reduce the charge as the battery neared capacity.

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I've found the best way to get a response from PodPoint is to raise your queries through the app when you look at the data from a particular charge and select the "Report an issue". It may take a week for them to get back to you but at least it will be from someone on the tech team and not the useless telephone answering team.
 
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