PDA

View Full Version : TP 3s2p and TP 2s2p in series


rhovie
08-07-2006, 10:59 PM
I have a Goldberg Tiger 2 converted to electric using Hobby Lobby's recommended setup--AXI 2826/10, 40 amp controller and TP 4200 3s2p 11.1 volt battery. Is it possible (and safe) to add a TP 4200 2s2p 7.4 battery in series for more power? The motor will take 5 cells, but not sure about the 18.5 volts, and what prop I could use to keep amperage down to 40--motocalc says 11x5 range. Thanks for any input--Bob

Mike Parsons
08-08-2006, 09:20 PM
Rhovie,
As long as the 40a controller and the motor can take 5s, you will be fine. That will give you a 5S2P 4200 of course. With the additional voltage you will need to drop down to an 11x5 or 10X7 I believe. Unfortunately unless someone has real world results, you might have to blaze a new trail on props that work.

rhovie
08-08-2006, 09:30 PM
Thanks Mike: I could try a few props and check with the Wattmeter to be sure and not exceed 40 amps, or maybe another battery setup for 4s intead of 5. I'd like to use some of the battery power I have, tho, cuz of the cost.

Sorry if I am using the wrong forum, I just ralized I should probably be in "power systems"?? Thanks again for the reply---Bob

Mike Parsons
08-08-2006, 09:49 PM
No problem. I hate to see a post go unanswered :).

I think trying it with the Wattmeter is a great idea as Motocalc is good at getting you in the ballpark, but I trust real numbers more. My motto is go with what you have first and try and make it work so good luck! :)

timocharis
08-09-2006, 01:13 AM
The only real trick from my point of view is to try to make sure the cells in both batteries are all within .01v of each other before you hook it up. This _may_ just happen, but checking the voltage and adjusting as necessary is a good idea.


Dave

Mike Parsons
08-09-2006, 01:23 PM
Good point Dave.
Bob, a balancer will help with this if you have one handy.