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Tech => Tech Help => Topic started by: TimothyNZ on November 16, 2014, 03:00:59 AM

Title: Testing an electric scooter with lower battery voltage
Post by: TimothyNZ on November 16, 2014, 03:00:59 AM

Hi all,

Firstly, I apologise ... I am very much a newbie to electric vehicles and to things electric in general. Secondly, I apologise if this is a common question covered elsewhere.

About a year ago I acquired two Italvel Day electric scooters (made in Italy), one without batteries and one with 9 x 12v 20ah lead acid batteries (long-discharged). There's not much info online, but I think the system was originally designed as a 48v system. It has a 1.25kw brushless DC motor and a proprietary Italian controller which has "108V 120A" printed on it. I am under the impression that both scooters were functioning normally before they were parked up for several years.

I am assuming that the old batteries are completely stuffed, but I would like to test that the controller and motor and other parts do in fact still work without going out and buying a lot of expensive batteries. I have 4 smallish (5ah) 12v AGM motorcycle batteries. My question is, can I test the system with a substantially lower voltage than it was previously running? Or will it a) damage the controller? b) damage the batteries? or c) not work at all?

Thanks. Tim

Title: Re: Testing an electric scooter with lower battery voltage
Post by: kingcharles on November 17, 2014, 02:54:18 AM

Hi, and welcome.
If the existing batteries are still wired up than you can determine the operating voltage from counting how many batteries are wired in parallel and how many in series.
Parallel: battery plus âž• connected to plus âž• of next battery etc. Voltage stays the same
Serial: battery plus âž• connected to battery minus âž– of the next battery. Voltage increases.
Serial and parallel can also be combined so ensure you check the complete set of battery wiring.
Testing with anything other than the original voltage will not prove much.
Good luck

   

Title: Re: Testing an electric scooter with lower battery voltage
Post by: TimothyNZ on November 18, 2014, 04:40:07 PM

Thanks kingcharles. All 9 batteries are wired in series, so I'm definitely looking at 108v. For the hell of it, I hooked up my 4 x 12v batteries today to see what would happen. I proved that:
1. The horn works! :-)
2. The low voltage warning light on the dash appears to work.
3. A couple of little lights came on on the controller itself, so at least it's not completely fried.

I will acquire the necessary 108v one way or the other and try again.

Title: Re: Testing an electric scooter with lower battery voltage
Post by: kingcharles on November 19, 2014, 04:58:51 AM

Wow, that's quite high voltage then!
Are you sure the motor reads 1.25kw?
Because 108Vx120A means12.5kw!!