truck stuck at full throttle

[ncalenda]

I have the li-saver and I had this happen 2 times now. When the li-saver senses the LIPO's voltages is getting low, all of the sudden the truck will go full speed. I have to run and grab it, take the cover off, and then unplug the batteries.



I have the li-saver soldered to the ESC, and the ESC plugs into the li-saver, then, the li-saver is plugged into CH2.

What is causing this?

When I charge the lipos, or use c-cells, it works fine.

Do you have the Li-saver that mike sells for cars or the airplane ones. The airplane li-saver does the full throttle thing and the car version doesn't. Unless it is some other problem.

[ncalenda]

It is the one from Mike, I just looked at my order, and it has this:

Li-Saver - car version

Could this be a mixup?

[nativepaul]

I cant help with this, but I fly electric planes and I'm very surprised that the aeroplane one goes to full throttle on cutoff, not only will that kill you LiPo but trying to land at full throttle before you battery gets killed and your radio dies would likely kill your plane too.

[ncalenda]

I can't think of any time when I would want it to go full throttle and stay like that.

Has anyone else ran into this? Or, have ideas to fix it? Do they have a device that I can use to tell me the Volts, then I could just read it and not depend on the li-saver full speed ahead.

[crazyjr]

Could it be reversed somehow? It seems to me if it sees full throttle as stop that would be the cause. I have no experience in them, just speculating

[zeropointbug]

What ESC are you using? BTW

[BrianG]

I wonder if the radio receiver is interpreting whatever signal the lisaver is sending as WOT. Do you happen to have a failsafe unit to try (just for testing)?

[ncalenda]

Originally Posted by zeropointbug

What ESC are you using? BTW

I'm using the 9920 warrior.

[ncalenda]

Originally Posted by BrianG

I wonder if the radio receiver is interpreting whatever signal the lisaver is sending as WOT. Do you happen to have a failsafe unit to try (just for testing)?

What is a failsafe unit? How would I test it?

[zeropointbug]

I had a problem like this, but it was my radio (stock TQ-3... i know:020: ) soon getting Spektrum dx2.0. But if I got too far away from the truck, it would go nearly full throttle and the steering would go off which ever way.

[ncalenda]

The thing is, I have a good radio, it is the Futaba Magnum 3PM-FM Pro. When it happened the 2 times, the truck was close, once in my back yard.

[BrianG]

ncalenda, I responded to your PM. If anyone else is curious, this is what I wrote:

Originally Posted by BrianG

Well, the lisaver is obviously doing something when the batts get low then. Now, it's a matter of what signal it puts out to the rx. The lisaver should be outputting 1.5ms pulses (which is "neutral throttle"), but unless you have an oscilloscope to verify this, it will be very hard to prove.

I suggested the use of a failsafe because a failsafe device reads the input signal, and if it is not a valid 1ms to 2ms pulse train (which could be caused by loss of BEC power or radio interference), it outputs a neutral signal (again; 1.5ms pulses) to the receiver. So, using a failsafe would help determine if the lisaver is outputting a proper signal when it kicks in. If the failsafe does help, then the lisaver is likely at fault. If it doesn't help, then something is probably up with the ESC.

I hope that made sense...

[miniGranis]

I had the same thing happen to me, I am using the 2.4Ghz 3PM and Hv-Maxx ESC. I have tried two Li-Savers (one from Mike and one off Ebay) they both did the samething (full throttle). I was in contact with Mike and also DMA (manufactor) and no one could tell me what the problem was.
Not much help but at least some info that you are not alone...
I switched to the CellPro DPM.

[BrianG]

Is there any type of little adjustment-type screw on it? Has anyone cut the heatshrink off to see if there are one of those surface mount pots on there? I'm hoping there is some sort of way to adjust the output signal to 1.5ms when the cutoff kicks in.