LRP Competition TC-Spec problem,
 

I am running a SPHERE Competition TC-Spec with heat sync and fan. A LRP X12 17.5T motor. Reedy 65C 5500 battery. On a TC6, geared between 5.0 and 4.71 throughout the day. I also used a Team Powers 17.5T to rule stuff out. I have the profile set on 6, brushless. The problem is that, intermittently, the ESC would stop for about 5 seconds, still have servo. It acts like the Hall sensor harness wasn’t plugged in. But it was. I even installed a brand new wire harness before the main. At about the 3 minute mark, it died again. Waited about 5 seconds and it came back to life. Finished the race from there. I don’t think it is thermal, because once it does it, it is fine from then on.

During practice it did it after a few seconds. And everytime I did, I made sure the sensor harness was plugged in on both sides. Just no rhyme or reason as to when it does it.

I wasnt geared near as fast as some of the other guys on the straight away, and they didnt thermal or cut out or anything. My drive train is smooth.

Any suggestions or should I just send it in?

you have it in lipo mode correct? try a different profile and see what happens then :nod:

Lipo Mode? Yessir. Different profile? Yessir. I used 3, 4, 5 and 6. Different gears, cable and motor. The only common denominator is the ESC. I think it is the circuitry of that board that the sensor cable plugs into. (Yes, all the pins are still standing)

then yah for sure its the esc no doubt :nod: it could be your esc to rx plug, if you have looked inside the case the wires could have gotten frayed and are glitching, which in this case if you dont have excellent soldering skills you will need to send in yes, which can be pricey depending on what really is the problem

LRP esc's come with a 25 cent switch. We had numerous shut down & intermittent stop & go's until we tried a better switch. You can just bypass the switch to test it. This goes all the way back to brushed esc's by LRP . That has been the only thing I had a problem with. The little blue switch enclosure will get filled with dirt & at the time I was only running on asphalt.

TM

Have you ruled out the power switch? if the esc cuts off even for a fraction of a second it will take it another few seconds to arm itself (with the radio at neutral throttle). Its not uncommon for a power switch to go bad.

Im unfirmilliar with the older LRP ESC's. I used to run them but its been long enough that I dont remember if they need to read neutral throttle to arm or not. It seems like a possible answer though.

No, I have not ruled that out. I will check that out and get back to you. That would be great if the problem was that simple.

You know what I just thought of along those same lines? Bear with me just a sec while I explain this. While charging my battery (Yes, I only have one right now) I did notice that occasionally it would get a cell count or voltage error while charging it. I have one of those 4 port chargers so I thought maybe the charge wires might have been bad so I moved it to another port and it worked fine. In hind sight, it may have just been coincidence that it worked fine on another port. I may have a loose conection inside the hard case. It has the banana plug set up on it, and I have the banana plug to deans plug adapter on it.

So along those same lines as you suggested, if for whatever reason I have a momentary open on my battery, it could act the same way as a switch problem. The other battery should be here today or tomorrow, so I will test that theory before I cut the swicth wire and bypass it.

is it a hobby people battery by chance? I used to sell them in my shop and they are good batterys till they take a couple hard hits. I've seen more than one short out like you suggested and for some reason if you pinch the pack right around the middle they would work fine. All the lipo's that I saw with this problem Hobby people was glad to warentee, and I kept them around for a cheap battery for a long time because they were so good about helping out the customers. I have since switched to carrying the Onyx lipos as a cheap hardcase lipo and havn't seen one with a problem in almost a year

No, it is a Reedy.

interesting. I've not heard of the Reedy's having any problems.. Let us know what you figure out :nod:

Sure will. I mean it is just speculation at this point. And if it turns out to be wrong and it is the switch or anything else, I will sure post it. I know LRP and Reedy are both well respected companys and I dont want to drag their name in the mud. Not that I can do that single handedly anyways. :)

What radio and receiver are you using? I've had more than one spektrum receiver do exactly what you described. Just throwing it out there that you might be chasing the wrong gremlin.

Airtronics MT-4 and RX461

Okay, the plot thickens. The new battery did the same thing. I didnt test the switch yet though. The reason I say it thickens is because I noticed that though it did it occasionally with normal driving, it did it EVERYTIME I wiggled the steering wheel back and forth.It would sit for about 5 seconds and take off again, as soon as I wiggled the wheel, it would stop again. I always still had steering even as it sat there waiting to come to life again. The servo is a JR z9100s. It runs smooth and no binding.

Another clue, is my radio will beep immediately the moment I dont have any power on the car. It never beeped when the car lost drive. So therefore, I dont think that the power switch OR the battery is the problem. I guess I have to send it in. If this was a plane, I dang sure wouldnt fly it. Any other thoughts?