4 electric Motor Set up (Lancaster) Question

[Gregor77]

Ok, I have to take it back one step and need help...


I have two questions that need clarification


Background: Picked up a Chris Gold Lancaster 90" WS, 19 lbs to obtain C/G  It came MH batteries Panasonic 1.2V X10 making it 12V total 3000 mah.  There were 4 batteries in the nose of the model and c/g was around 25% of the leading edge.  The motors are Axi max 5S spec but the ESC's are rated for 3S max.  I hooked up some 3S 2200's and there is loads of power with 3S. 


Q1) I want to go with Lipos, due to the weight and amount of space, 12V from the Mh batteries is 12 V, 3S is 11.1, I assume the power will be the same.  Do I go with 3S, 5000 packs X4?  The weight is still a bit less than the Mh.  I don't want to add more nose weight if not needed.


Q2, the plane came with some JR spektrum equipment, one looks like a box with two battery leads in it with a white button?  The person also labelled some battery wires that say Switch and Hot?  The RX has wires that say Battery one and battery two?  I am a bit confused.   My assumption is that this is a back up power if the first RX battery gets low.


Q3) All the motors spin freely except the right inner one appears to have a brake on it.  Is this normal to counteract the torque effect of all the motors turning the same way or a set up issue?  I want to know if I should reprogram the esc and take the brake off.


Guys this plane is massive!  After a good wash, it looks good and I touched up some of the hangar rash.. looks great!

[Ededge2002]

Q1:  the voltage under load will likely be higher with the Lipoly cells and you will have more usable mA available.  Both gains!

Q2:  This is a big plane and quite possibly has a redundant battery system in it.  I would do some testing to see if it works as I suspect by pulling one battery pack off at a time and seeing what happens (no motor batteries or props!!).  A photo would be helpful or a model name if there is one visible.

Q3:  I would suspect all should be the same.  Personally I would have all motors with break turned on so if there was ever a motor trouble there would be some chance of deadstick landing.  All those props windmilling would make a huge amount of drag. 

[piker]

For reference, My Sandringham is powered with 3s x 4400mah per motor drawing about 30A.  Weight WAS about 16lbs.

[Gregor77]

I just ordered 4X 3S, 5000 packs and an extra RC pack.  I just hope it is enough weight..