splinter

My Feedback: (64)

I hope someone can help me with this

I recently converted my Aerowork's 30 % Yak from Gas to electric I installed a Rimfire 50 cc and a Castle 120 amp HV ESC
After 5 or 6 very nice flights using 2 /6 cell 5000 mah batteries (50 C )

I tried a new set of batteries 5200 mah 75C . The brand is Zeee and 3 seconds after take off the motor shut down and unfortunately took the gear off the plane.
By the way I'm running a 22x10 falcon prop

I certainly didn't overheat Could these batteries be too much?

I really don't understand Can anyone shine some light on the problem

Bill

flyinwalenda

My Feedback: (5)

You didn't state what cell count these batteries are but if they are 6 cell then they are not "too much". The 75C rating means that the pack can(or should be able to) deliver around 390 amps in a burst. but only if the motor/prop setup demands it.
If the setup only demands 275 amps then that's all the packs will deliver.

I've never heard of these batteries so I would suspect the quality of the packs first, especially if you have several good flights on the 5000mah packs. Run an internal resistance check on the packs and see how healthy they are.

The ESC may have shut down because it may have determined the batteries reached low-voltage and turned on LVC killing the motor. Bad packs could have caused this.

oliveDrab

Did you place a cell checker on both of your 6S batteries? You should have approximately 4.2Volts/cell ... maybe a little less. Do you have any cells that are significantly lower than the others? More than .1 volts lower.

oliveDrab

[LEFT]Did you test your amp draw on the ground with an in-line volt/amp/watt meter? With the plane on a test stand and the meter plugged in-line between the battery and the esc, throttle up and verify how many amps are being drawn at full throttle.

Here's some specs on that motor:RPM/V (kV Rating): 230
Input Voltage: 33.3-55.5V (9-15S LiPo)
Connector: 6mm bullet plugs
Number of Poles: 14
[I][B]Max. Constant Current: 110A (at 12S)

splinter

My Feedback: (64)

Gentleman
Thank all of you for your advice. The batteries I've used in a smaller plane individually and work great. I use the new Hitec X4 charger and of course balance all my batteries. Also I've been in hobby 30 years and flying electric when we had brushed motors and nicad batteries
Thanks again will try ideas

Bill

oliveDrab

Yes - that was my next question. Sounds like you're doing everything right.