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Thinking of buying a Granny cable as I'm moving house and not sure how long it will take to get a charger installed.
Is it advisable to buy an official Renault cable? Are there any cheap ones that are recommended... Or any to avoid for that matter?
I've heard they can be dangerous/prone to overheating ... is there anything I can do to make things safer? Would it be a good idea to limit charging time? My round trip to work will be 24 miles so I don't need a full battery.
 

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We used a genuine Renault branded granny cable for 15 months without any issues whatsoever. We also have a Nissan branded granny cable which is exactly the same as the Renault cable apart from the branding. AFAIK any Type 2 granny cable will be suitable, if that’s not the case I’m sure there’ll be comments soon.
 

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ZOE Q210 Oct'13
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Type "evse cable" into an eBay search and go for one from a reputable name (BMW, VW). They all seem to be about £185 which is much better than the ridiculously priced Renault one. Don't get the Nissan Leaf Type 1 version, as it won't fit your car.
 

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I agree with @andyfras. My only comment would be to say,'be careful when using extension leads'. Official statement is to avoid using them. My son-in-law has just converted my un-tethered charger to a tethered one, but we didn't have the resistor required to complete the job. I had to rely on my genuine Renault 'granny cable' (compensation for the 'stop electric failure danger' debacle on my previous 22 kWh Zoe), but I didn't have an exterior socket to plug in to. I had to pass an extension through the letter box (shortest length and completely unrolled) and the plug got seriously 'warm' during charging. Needless. I didn't charge overnight.
 

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I have a i3 bmw granny cable for my Zoe 40 works great and does not over heat or get warm if i use it on its own.
But if i use a *extension cable i found the Plug that goes in to the wall socket gets slighty warm.

* i used a 25 amp rated cable for the extension cable
 

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I always found the "Duosida" brand generic from eBay to be good. 13A I believe.

If you have a Q90, the charge times are painfully slow. It's a realistic option for charging R models overnight though.
 

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UK plugs have a max rating of 13 Amps, but for various reasons you're not going to get more than about 10 Amps safety. 13A extensions leads designed for outdoor use normally have a thermal cut out on them. You need to fully unwind them. They will get warm but the temperature will stabilise.
A Granny charger isn't a long term solution - you end up wasting about 30% of the power in heating up cables and in the charging control systems.

Some of the Granny chargers have temperature sensors within the domestic plug as an extra safety measure (so don't cut off the end to replace it with a longer cable!).
 

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A Granny charger isn't a long term solution - you end up wasting about 30% of the power in heating up cables and in the charging control systems.
Really? Do you have a source for that? Clearly there are losses, but 30% seems a bit wild. My granny charger draws 10A (current clamp measurement confirms this), car reports charging at between 2.1 and 2.2 kW with a supply voltage of 230V. I reckon I'm losing about 100-150W before the car - I do accept that there will be further on-board losses, but range added indicates they are minimal. Seems highly unlikely that I'm losing the best part of a kilowatt though.
 

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Co-author of CanZE. Q210 nov 2013
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The truth is somewhere in the middle. I agree a granny charger is more a safety net than a permanent solution. Reasons are more safety and power rating (convenience) related.

A big misunderstanding is the amp rating. ZOE draws 6A reactive current while charging. That adds to cable losses but it does not count towards actual energy transfer. A common mistake goes a bit like "10A at 240V, for 10 hours, oh my, 24 kWh went in and I see only 15 kWh added to the battery. It must be very inefficient". In reality, on a 10A setting, only 8A is related to real power (vector addition), so only 19 kWh went in.

There are more subtle effects that make low power a bit less efficient. However, in the light of this discussion, a more useful number would be the difference in efficiency between say 3 x 16A charging versus 1 x 10A. That difference most certainly is not 30%.
 

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I think we calculated a while back that it charges at 1.8kWh at the battery after losses.
 

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I used my granny cable just to top up overnight in a lodge while in south wales on holiday last year , Just as Geniepoint ( aka Dragon Charging in south wales ) had finised installing around 10 22kw chargers in Tenby , Pembroke Dock , Milford Haven , Fishguard ,Newport , St Dogmaels , Aberaeron and now
Tesco have also just installed some 7 kw chargers too . Plus a Polar Rapid at Wolfscastle Country Hotel .

I think of it like carrying a small can of fuel can around just in case. 🤞
 

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