Hmm, Ansmann Xirius power loss

soane · #1 19-01-2011

This is my first brushless system that I have used and I've installed into my Ansmann Macnum and I've already run into problems. At the moment I'm running a 19t pinion and a no-brand 5000mAh Ni-Mh battery, if I accelerate with full throttle it will cut out but if I feather the throttle to full throttle it will run OK. These are the specs of the kit:

Sensorless
60A continuous load
Short-term exposure 300A
4-10 cells NiMH / 2-3 LiPo cells
Forward / Reverse / Brake
Reverse: soft 3 modes (soft, medium, aggressive)
3 accelerator modes: soft, medium, and aggressive
Brake: 4 modes
Overheating protection
LiPo Low Voltage Protection
Fans

Would I be right in thinking that the Ni-Mh isn't capable of keeping up with the demand of the controller? I fitted a 24t pinion and I cannot get full throttle at all. Would I be better changing the acceleration curve?

Whiskers · #2 20-01-2011

Have you got the voltage cut off turned on?

ch!3f · #3 20-01-2011

that may be the problem alot of non branded batteries dont have a high discharge rate so the esc struggles to get the power hence cutting out,

when it does cut out does it do it for a few seconds or can you put the throttle straight back on again? normally a voltage cut off lasts a few seconds

sosidge · #4 20-01-2011

Quote:

Originally Posted by soane

Would I be right in thinking that the Ni-Mh isn't capable of keeping up with the demand of the controller? I fitted a 24t pinion and I cannot get full throttle at all. Would I be better changing the acceleration curve?

Sounds like the battery is the problem. Can't hold enough voltage under load.

You can try softening the ESC settings, or running smaller pinions, but it won't solve the fundamental problem.

soane · #5 20-01-2011

I'm charging the battery back up tonight, I'll check the set-up with the card, problem is there is no explanation with the programming card of what does what. I'm also going to speak to Shaun from Ansmann tomorrow, see if he can shed some light on it.

soane · #6 20-01-2011

Quote:

Originally Posted by ch!3f

that may be the problem alot of non branded batteries dont have a high discharge rate so the esc struggles to get the power hence cutting out,

when it does cut out does it do it for a few seconds or can you put the throttle straight back on again? normally a voltage cut off lasts a few seconds

It's as if as it accelerates the power goes off, I return the stick to neutral then reapply it accelerates again but never reaching full power. If I hold the stick forward it won't pick up the power again.

soane · #7 20-01-2011

Cracked it, it's the battery, I stuck it back on a charge and POP it flies. I think I'm right in assuming the speed I'm seeing now will be on par with a lipo? I'm reluctant to jump in with both feet into lipo as this (for now) won't be raced, any idea how long a run I can expect from this NiMh? I'm hoping for reasonably good times as the motor is more efficient.