Ping batteries in series (version 2.5)

[azisme]

Yes I know this has been discussed over and over again on this forum, but I want to be absolutely sure I am wiring up my new batteries correctly. I also want to post the drawing I made to help out others following a similar path.

I have ordered and received two custom 30 volt 15Ah batteries and two custom 37.5 volt chargers from Ping. I am going to hook them up in series for a 60 volt, 15Ah hour system. I already have a controller that is rated from 36 - 72 volts and a Crystalyte 408 front hub motor.


My first question is: does the schematic look correct? I am 90% sure it is, but I have a lot invested so would like some additional reassurance.

My second question is: Can I leave the batteries hooked up to the controller while I am charging the batteries? Can the controller still be turned on while charging or do I need to put in some kind of safety to make sure I don't forget to turn off the controller while charging?

 

[dnmun]

you lost me on the 'two' custom 30V15Ah packs and the 37.5V custom charger. why did you decide on such strange values?

 

[azisme]

30 volt packs because I did not want to push the limits with a total of 72 volts, and I wanted a bit more speed than I was getting with my old 48 volt battery. 37.5 is the recommended charging voltage for 30 volt packs. I did not pick the voltage for the chargers, Ping did.

 

[dnmun]

ok, mr ping custom built 2 10S packs for you and ecitypower charger set to 37.5V?

you actually could use the 2 36V packs in series. most 72V controllers would work fine off of that. or you could have modified a regular controller with high voltage caps if it has the p75fn75 FETs.

i did an upgrade on the 9 FET infineon that comes with the E-Bikekit.com 9 continents hubmotor. i bot 2 boxes of 100V1000uF caps on ebay to use to upgrade the 36V controllers to 72V nominal lifepo4. i sell them for 30 cents each plus postage.

http://endless-sphere.com/forums/viewtopic.php?f=2&t=10222

 

[azisme]

I did not want 72 volts and I did not want to spend the extra money for the additional voltage. Ping did not ding me at all for custom charges.

Can we get back to my original post?

 

[dogman dan]

Y'all know how stupid I am with electronics, but that diagram looks wrong to me. For a series connection, battery 1 has its positive going to the controller, and it's negative going to the positve on battery 2. Then the negative of battery 2 goes to the negative on the controller.

I still don't fully understand how the diode gets wired into the harness. Brain must have some shorted halls.

To charge, you disconnect the two batteries where the wire goes between them from positve to negative.

 

[nicobie]

Listen to Dogman. Don't hook up the 2 batteries like your diagram shows.

You need to read this thread:

http://endless-sphere.com/forums/viewtopic.php?f=16&t=1312

 

[fechter]

Your diagram is correct except for the markings on the right pack.
Here is a corrected version:

The only other thing is the charger outputs must be isolated to charge both packs while connected. I don't know if Ping chargers are isolated. You can test them with an ohmmeter.

If the chargers have 2 prong AC plugs, there is no worry. If you charge with packs separated or one at a time, there is no problem either.

To test if they're isolated, unplug everything and measure resistance from the ground pin on the AC plug to both + and - output wires. If you see either measurement is near zero ohms, then the charger is NOT isolated and must not be put in series with another charger.

 

[azisme]

Thanks dogman and nicobie. I have read the thread you referred to and I also have a diagram from Ping. I guess where I am confused is which wires are the controller wires, and which ones are the battery wires. The batteries have 2 red wires that both appear to come from the battery, not the controller. One is thicker than the other. Then there is a blue wire and a black wire that come from opposite ends of the controller. My diagram shows the thin red wire and the blue wire going to the charger.

Here is the diagram Ping sent me:

 

[azisme]

Thanks fechter! You caught me in the middle of replying. Yes, I had a simple typo on the right battery. It was late last night when I drew it.

Can't wait to get it going. I have the Anderson connectors on order.