Granny Charger

[kaiz]

Calculation: Full speed gives me abt. 56 km/h * 0,2 kWh/km (av. consumption) = 11,2 kWh/h
Reduced speed gives me abt. 23 km/h * 0,2 kWh/km (av. consumption) = 4,6 kWh/h
It is with 3ph. charger. Granny takes too long.

[Daveion]

"Internally something does not have to be much hotter that 32C, to have an external temperature of 32C.

Over time the whole plug will get to nearly the same temperature as heat from the inside will be conducted to the outside through the plug. Once at the surface of the plug the heat will only be convected slowly away by the air which has a low thermal capacity and so the temperature will equilibriate towards the internal temperature"

Thanks Simonrg
Thats a really good point. As long as the temperature stabilises then there will be little difference between internal and external surfaces.
Less bothered by this now. Thank you.

[HeidiFlowerpt Driver]

I just read a thread on another forum about granny chargers. The OP wanted to know how to replace the 13A plug on his granny lead. He'd cut the old plug off and was surprised to discover six wires in the lead, not the usual three. It turns out his lead had extra wires connected to thermistors inside the plugtop, likely to provide thermal monitoring to ensure the plug doesn't get too hot. If such protection is standard on granny chargers that's brilliant.

[Sindidziwa]

I only get 7 or 8 mph with my granny charger. If I switch on the AC to warm the car up this then drops to 2 mph! The plug does get warm but not excessively. My Granny Charger was £165 from Screwfix - couldn't justify the Zappi chargers etc when we're mostly at home but I'm on Octopus so i use Alexa and a wifi connected plug to program the charging for the cheapest electricity - always better when it's windy. I'll soon be charging on sunny days as my PVs generate 3.6kW at full blast and I'm only charging at 2.3kW.

[Daveion]

I just read a thread on another forum about granny chargers. The OP wanted to know how to replace the 13A plug on his granny lead. He'd cut the old plug off and was surprised to discover six wires in the lead, not the usual three. It turns out his lead had extra wires connected to thermistors inside the plugtop, likely to provide thermal monitoring to ensure the plug doesn't get too hot. If such protection is standard on granny chargers that's brilliant.

Thats interesting. Might explain why the cable to the smart box component is so fat. My temerature checks revealed nothing more than a plug that reaches 32C and is stable at that level throughout my charge. Longest charge so far 9 hours 35 mins.