[hhughes]

Hello,
I just replaced two 12vdc batteries in my 48v MILES EV ZX40 2007.

Charged it up overnight, showing full power around 52Volts on dashboard.
Took off and topped out at my typical 28mph.....

ONly went two miles when:
I went up a slight grade and then motor seemed to die to a crawl.
My output from my controller is near 0, enough for me to get back to my garage and recharge the batteries.
Reverse works just fine.....

After overnight charge, batteries back to normal 52v, but still no juice getting to the motor.
what is my problem?
thx
Howard

 

[major]

I just replaced two 12vdc batteries in my 48v MILES EV ZX40 2007.....what is my problem?

Hi Howard,

Have you contacted Miles? What did they say?

You have to go back to the guy who sold this vehicle to you. If that guy won't help, you might find some assistance here. But I'm not sure any of us DIYers are familiar with Miles EVs, so please post up schematics. I don't even know what motor and controller those things used.

Regards,

major

 

[peggus]

What's the battery voltage when you loose power?

Why did you replace only two batteries and what did you replace them with? Same brand and type?

 

[DavidDymaxion]

Hopefully not too silly a question, but are you sure the new batteries are good? Have you checked the voltage of each individual battery at rest, and then under a load?

Another thought, are all your connections tight? I've had cases where you could check voltage just fine, but not pass any real current.

Hello,
I just replaced two 12vdc batteries in my 48v MILES EV ZX40 2007.

Charged it up overnight, showing full power around 52Volts on dashboard.
Took off and topped out at my typical 28mph.....

ONly went two miles when:
I went up a slight grade and then motor seemed to die to a crawl.
My output from my controller is near 0, enough for me to get back to my garage and recharge the batteries.
Reverse works just fine.....

After overnight charge, batteries back to normal 52v, but still no juice getting to the motor.
what is my problem?
thx
Howard

 

[dtbaker]

Hello,
I just replaced two 12vdc batteries in my 48v MILES EV ZX40 2007.

ONly went two miles when:
I went up a slight grade and then motor seemed to die to a crawl.

After overnight charge, batteries back to normal 52v, but still no juice getting to the motor.

sounds like more batteries are bad, or connections are loose, or you boiled all the water out of some...

with a highly unbalanced pack, the weakest ones really get hammered.