Can MPII handle 2x48/10 batteries?

[Zero]

With 1 battery i'm seeing around 25 amps, and I read somewhere that mp2 is rated at 35 amps....so my question is - will I fry my pie, if I add another battery in parallel?

[MAGICPIE3FOCUSPOWER]

Magic Pie II is rated to 1000W so....make some calculations...

[Zero]

im running it at 1400w currently, and its never been hot or anything, and I recall seeing a picture of gm bike with 2 batteries...

[MAGICPIE3FOCUSPOWER]

Well just try and keep the motor temperature in mind

[GM Canada]

Three 48v10's in parallel no problem.

Gary

[Zero]

thats the answer I needed, how did you wire them, 3 into 1, or with diodes?

[GM Canada]

I just paralleled 3 into 1. You can see in this link when I did my townie, some of the close ups show where the wires all attach together.

http://goldenmotor.com/SMF/index.php?topic=4099.msg24164#msg24164

Gary

[Zero]

first ride with 2 batteries done, but I actually didnt see any increase in numbers, maximum wattage remained the same as with 1 battery, then its just the ~1400w the mp2 handles, and thats it, or can I configure it with usb cable to accept more amps?

[MAGICPIE3FOCUSPOWER]

You need voltage for more power...
More voltage more rpm = more watts...

[Bikemad]

Doubling the capacity of your battery does not necessarily give an increase in the power, but it should double your range.

If the current draw is limited by the controller, adding another battery in parallel is unlikely to make much difference to the overall power.

To get more power you need to either increase the current and/or the voltage being supplied to the motor. A higher current will produce more torque and the higher voltage will produce more speed.

The GM controllers are usually factory set for maximum current, so any software adjustments carried out with the aid of the USB cable would not increase the power output.

To increase the power you will need to modify the internal controller by increasing the shunt which will result in controller failure if it is increased too much:


or alternatively you would have to rewire the motor to enable a higher power external controller to be used.

Alan
 

[Zero]

mmkay, I was already set to buy the cable, and see if I could meddle with setting to increase amperage, at the moment i'm getting max 1400W, that would be ~25 amps?
Interestingly, the software shows max setting of 50 amps, but the shunt won't let that much thru anyway?

[Phil O Dendron]

Zero, what revision of the cruise controller software are you using?

When I used the version 200, 50 ampere was the maximum setting for peak current.
Now I'm using version 282, that allows 70 ampere (If I remember correctly).

Maybe this helps quick & inexpensive.

cheers, phil.

[Zero]

But does the controller actually USE that amperage without hardware modification? I haven't bought the cable yet, as I'm still unaware if it will do me any good?
So the question is: if I buy the cable, and modify settings, will my mp2 accept more than the current peak of 28 amps@48V?

[e-lmer]

You have to be concerned about peak and continuous Amps.

If you run at the Peak Amperage for very long you heat up everything,
possibly melting the insulation on the winding wires, or frying the controller.

The factory setting is such that an ordinary user will not burn out stuff
without trying very hard.

Upping the max current above the max continuous current means that you
are A) voiding the warranty, B) taking responsibility for either limiting the temperature or sinking it somewhere.

[Zero]

That is all well and good, and i'm totally aware of the dangers, local dealer has a spare mp2 controller in stock, already checked
But when I bought the pie, I received info that its unrestricted, and I figured my 48/10 battery gives out about 30 amps, now I have 2 batts, but absolutely no change in power numbers, that made me think now - is it the shunt, or is it restricted? But i'm already getting a cable next week and will find out where is the problem.