RC-Monster Forums - View Single Post - Investigation ...6s1p or 4s2p, neu, cc neu...

MrMin · 04:24 PM

Just for fun, I tried to work out why a
2x Series 6s, 5Ah can have longer runtimes than a
2x Parallel 4s, 8Ah ... Taking into account most of the various factors.

Thats a HighVolage vs a LowVoltage system:

HV: Batt Internal Resistance in series (PRO)
Is cooler (less current in wire resistance) (PRO)
Run chance of cells discharging unequally (CON)

LV: Batt Internal Resistance in parallel (PRO)
Gets hotter (due to wire resistance - more current) (CON)
Better for cells discharging equally. (PRO)

I suppose the bearings and friction do not play a big role and then there is the foucault current and other losses.... (does anyone know the potential foucault current losses?)

Basically I think the cooler system with the lower kv is the better.
Only why is the lower KV motor better? Has it something with the characteristic efficiency curve? Dyno graph? What other factors play a role here?

Who is going to investigate this with me?

How can we find out about the materials of the rotor and stator and wire resistance...etc..

	(#1)
MrMin RC-Monster Carbon Fiber Offline Posts: 57 Join Date: Aug 2008	Investigation ...6s1p or 4s2p, neu, cc neu... - 02.23.2009, 04:22 PM Just for fun, I tried to work out why a 2x Series 6s, 5Ah can have longer runtimes than a 2x Parallel 4s, 8Ah ... Taking into account most of the various factors. Thats a HighVolage vs a LowVoltage system: HV: Batt Internal Resistance in series (PRO) Is cooler (less current in wire resistance) (PRO) Run chance of cells discharging unequally (CON) LV: Batt Internal Resistance in parallel (PRO) Gets hotter (due to wire resistance - more current) (CON) Better for cells discharging equally. (PRO) I suppose the bearings and friction do not play a big role and then there is the foucault current and other losses.... (does anyone know the potential foucault current losses?) Basically I think the cooler system with the lower kv is the better. Only why is the lower KV motor better? Has it something with the characteristic efficiency curve? Dyno graph? What other factors play a role here? Who is going to investigate this with me? How can we find out about the materials of the rotor and stator and wire resistance...etc.. Last edited by MrMin; 02.23.2009 at 04:24 PM.