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Discussion Starter #1 (Edited)
Renault website says "Home Wallbox 7,4kW (32A) Included" and keeps referring to 7.4kW. Chargemaster site says it's a 7kW (30A) charger they provide. I have a feeling the 7.4kW measurement comes from back in the day of the British Gas home charger deal (and I believe Rolec have a 7.4kW / 32A model also) and the page wasn't updated.

I've pointed this out to Renault who rung Chargemaster and confirmed it is 30A and have gone off to investigate if this has a knock on effect with the charging times.

This community seems to be a knowledgeable bunch and would probably appreciate the intellectual discourse. How long are you finding the Z.E.40 takes to charge to 80% off the Chargemaster charger? Bang on 5 hours or slightly over? 5 hours 10? 20? 30? Or are the times correct and the 2A difference doesn't make a difference because physics?
 

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Why are you worrying about charging to 80% on a home charger? Normally you would plug it in in the evening and unplug it next morning. Typically it will be at 100% by then and the batteries will have been balanced. Balancing takes place at the end of the charge cycle and attempts to level the load over all the batteries. This is a good thing and should be done now and again.

Edit: although I said plug in in the evening and unplug next morning. I only need to plug in one or two times a week, but that is the method I generally use.
 

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Discussion Starter #5 (Edited)
80% because the slidey bar on the Renault website defaults to it and encourages you to care about the "to 80%" time (showing everything above that slows down and illustrating so in a different colour).
Calculate the charging time for your Renault ZOE according to the battery, engine and charging equipment. Remember, your home Wall-Box* is included with your ZOE purchase and charges at 7,4kW.
...but it doesn't.

Agreed Z.E.40 Zoe won't need charging terribly often and I probably will *mostly* charge overnight.. but say you've been away all week with work and haven't been very disciplined with your seeking out of public charging and you get home Saturday morning and you're thinking of charging it up a bit to make a long drive to see your aunt (so you're thinking "ah I'll set off at 2pm, Zoe should be ~ 80% by then") then it would be interesting to know how long it takes and whether that .4kW would make a difference.

Ideally I'd be interested in the charge speed to 100% too, but I appreciate all sorts of weird calculations kick in then as the charge starts to slow.. and you probably wouldn't wait around when you start to hit diminishing returns.

I know we're probably talking not large numbers in the grand scheme of things.. but the Renault website says it's 5 hours to 80% and it may not be.. so I'd like to know what it is then :).
 

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encourages you to care about the "to 80%" time
This is because all the 'away from home' charging is rated on how long it will take you to get to 80% IE: car A charges to 80% on a rapid charger takes 15 minutes whilst car B take 30. It's all about advertising which is the better? car.

Charging at home doesn't have to bother with all that because it's not rapid, in fact in most case it's not even quick.

It could also be because the new Zoe's big battery takes so long to 100% on a home charger, they don't quote that figure.
 

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The long explanation is that the battery management system tapers off charging the higher the state of charge is, so the last 20% takes (much) longer than the first 20%. It's all quite complicated based on battery type, temperature, position of the moon and then some, so the marketing dumb-down tale is "to 80%".

There is ZERO reason to stop charging at 80%. Battery stress is managed by leaving some extra room, iow, 100% in the dash is not really 100% of the battery; more like 95-97%.
 

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Power is current times voltage.

Most chargepoints support maximum currents of either 30A or 32A.

But the supply voltage at your home could be anything from 207V to 253V (230V is nominal; around 240V is common).

So with a 32A chargepoint the actual power could be anything from 6.6 to 8.1kW. 7.4kW is just the nominal output at nominal mains voltage.

A 32A chargepoint will always be faster than a 30A one at a given location, but there's not much point speculating about actual timings since your local supply voltage could have a much bigger effect anyway.

And unless you do 50,000 miles a year the reality is that even a 2kW granny charger is more than fast enough to keep the car topped up.
 

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Also there's a much bigger and more important point here:

Home charging times are irrelevant.

If you're not already an EV owner I get that this is not obvious, and that you are probably worried about a) how far the car will go on a charge, and b) how long it will take to fill back up afterwards.

One of the big epiphanies you will have once you get your car is that the second question is totally and completely irrelevant. Cars spend so much of their time sitting parked and idle that it really doesn't matter in the slightest whether your chargepoint is 10A or 30A or 32A or single phase or three phase or whatever. You get home, plug it in, and get on with your life.
 

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Discussion Starter #11 (Edited)
If you're not already an EV owner I get that this is not obvious
On order still.. probably delivery in October :).

It could also be because the new Zoe's big battery takes so long to 100% on a home charger, they don't quote that figure.
..but they do and that was my issue. I'd rather they quote the correct figure or don't. It's not fair for them to quote an incorrect one as part of the sales literature.

A 32A chargepoint will always be faster than a 30A one at a given location, but there's not much point speculating about actual timings since your local supply voltage could have a much bigger effect anyway.

And unless you do 50,000 miles a year the reality is that even a 2kW granny charger is more than fast enough to keep the car topped up.
Fair points. Thank you :).

There was a bit of toing and froing with Renault (they first gave me a time off Chargemaster of "3 and a half hours" which I pointed out was probably for a public charger and that was even less time than the current quoted time!) and they eventually just deferred to a Chargemaster supplied statement of "4 to 6 hours" and that they'd update their website.
 

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I charged mine Thursday night it took 2 hrs 44 min to get from 60% to 100 % (includes balancing). If I now add in the times - 22:02 to 00:42, you'll see that it took me absolutely no time at all as I was on my computer on SpeakEV and then I went to bed. In the morning it was fully charged and waiting for me to use:).
 
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