battery

Help & Support Robot Parts
1

Hi
I have Graupner Ultra 3500-6M

water-cooled
Motor Voltage 28V Voltage range 20-30V Rev/min unloaded 12200 Current when loaded efficiently 30A Efficiency 86%

And i have garupner mc-hydro 55 reverse
**[size=3][font=Arial]Specification[/font][/size] Operating voltage 8,4 … 36 V
No. of cells 7 à/to 28
Max. load forward 55 A
reverse 30 A
EMK-brake
Over-current protection
Temperature protection
Opto-coupler
Power-on pulse suppression
Clock frequency variable to 2,6 kHz

I want to know what strength lipo batteries I can use in max volts? for this set-up

Best regards
Reza**

2

Hi Reza,

Since your motor can take up to 28V and your motor controller up to 36V then you should be safe with a 6s LiPo battery.
The discharge capacity would have to be above the 55A of your motor controller.

We do not have any 6s LiPo at the moment but you could use two 3s making sure you charge them both before connecting them together (unless one battery will charge the other).
Any of these should be able to provide enough current, the smallest is 2500mAh at 30C which give you 75A of discharge and in theory you will use two so 5000mAh at 30C.
11.1V, 3000mAh, 40C 3S LiPo Battery
11.1V, 4000mAh, 40C 3S LiPo Battery
11.1V, 3500mAh, 30C LiPo Battery
11.1V, 2500mAh, 30C LiPo Battery

:slight_smile:

3

thanks for your answer would like to ask if I can use lipo 6s 22.2 volts?

4

Hi Reza,

That’s exactly what we just suggested, a 6s LiPo battery.
When dealing with LiPo you have to know that they will be 4.2V fully charged per cell, this mean 6 x 4.2V = 25.2V.

:slight_smile:

5

many thanks for your answer now, I am sure that I understood

6

have one more question do you know how fast such a mortor can sail

7

Hi Reza,

We do not have much background with boat motors and the propeller and hull shape will impact the speed.

:slight_smile: