Extension cords

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Zoe-M
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Extension cords

I was reading the owners manual and saw that it says using an extension cord could damage the charger and will void the warranty. I have not needed to use one but I fail to see how a properly rated extension cord could damage the charger, can someone explain this to me?

HarryS
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Re: Extension cords

It's all aout voltage drop. If you get a 12gauge extension cord rated for 20A, your voltage drop for a15-20 foot extension cord will be minimal. I still measure 122Vat the end of mine and the charging works fine. The issue is that the bike draws constant power, I.e.wattage. As the voltage drops the current draw incases, conceivably beyond the rating of your breaker if it were 15a.

kingcharles
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Re: Extension cords

I use an extension cord every day. But I live in a 230v country so I draw less amps.
I bought a 16 amp 10 metre cord from the local DIY shop and no problems so far.

Just make sure you get a properly rated cord and there is no issue.

Once you go EV, Gas is history!

mesman
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Re: Extension cords

There's some confusion about using extension cords. For mine, the first manual, the one that came with the Vectrix, stated to NOT Use an extension cord for charging.
Later I received a new manual in the mail. This manual was quite thick because it came in several languages. In this manual, on page 29 of the English section it says "Though it is not recommended by Vectrix, if you use an extension cord to charge the bike, make sure that it is a least a 20A cord and it should be no longer than 25ft (7.6m) in length."

I ride to work and back quite often if the weather is nice. Its about a bit over 25 miles one way. Before I bought the bike I checked with work to make sure I could charge it there. However the outlet at work isn't close enough, so I have to use an extension cord. I picked up a 25ft 12guage cord from a local store. It seems to work fine for me, and I've never had problems charging. However, looking at the Kill-a-watt on the far end of the cord, I can see there's a Significant drop under full load. Its enough that I'd be worried if it dropped any more.

As for why there could be damage; well its just not good to make electronic devices try to operate outside the voltage range they were designed for. This application is heavy duty voltage transforming, rectifying and charging, so is probably not demanding as sensitive electronics, but there's still a potential for damaging the bike.

AndY1
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Re: Extension cords

It mostly depends on the mains voltage used in your country.
USA has 110V-120V and because Vectrix draws 1500W (batteries) + aprox. 150W (fans+charger), it draws 1650W/120V = 13,75A. It the mains voltage is 110V, the current draw is at 15Amps and that is quite high. Add a long extension cord with low wire thickness (1.5mm2- and your voltage drops even further).
In Europe, our mains Voltage is 220V-230V. So 1650W/220V = 7.5A.

Remember, heat dissipation is R*I^2. The heat released with resistance increases with square of the current, so in case of 110V (15A), there's 4 times more generated heat than at 220V (7.5A).

And longer the cord, with higher the current and lower the voltage, more heat is generated when under load, because load lowers voltage even further and raises current drawn.

And that's what hurts the charger - all that heat generated with lower voltage and higher current.

My 'extension cord' from my apartment to the underground garage parking space is 60m long. That's why it is 5mm^2 thick (single wire thickness), but still the voltage drops from 230V in the apartment to 220V in the garage, when under load, but that's still well within acceptable limits. There's also quite cold down there. The highest I've measured in the summer (37°C outside) was 19°C (-2nd floor of underground garage :-).

Zoe-M
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Re: Extension cords

Thanks for the advice everyone.

Webmaster
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Re: Extension cords

I've added a resource page going over charging EV's through extension cords and adapters ... http://visforvoltage.org/book/ev-charging-charging-stations-extension-cords-charging-networks-etc/13823

- David Herron, http://longtailpipe.com/

Kocho
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Re: Extension cords

Also, if you are running the Laird's firmware, the charging current is 1/2 the original. It is about 6A max, perhaps a bit more if we factor in some inefficiencies in the charger.

So, this means, just about any 15A-rated (or more) extension cord would have no problem handling these 6-7A of current and your charger will not work extra to maintain that current with an extension cord. I use a medium dury 15A orange cord (the garden variety sold in the US) that is about 30 feet (10m) long and it barely warms-up at the plugs, cold everywhere else. My vaccum cleaner warms-up its extension cord more during use, so I'm not worried. That is all at 110V in the US. In 240V countries, it will be even better and longer extension cords can be used.

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