Wow

[ReV:-O]

hi guys

just got back from day 2 of running, and this time my results seem more normal. runtime was about 30 minutes, which is still very good for two 5000mah packs.
MMM was warm, but the motor was hot. i have a handheld temp gauge but it was difficult to take readings with the body on, but i did my best. it was 120F, so i know i have not damaged anything. would it be better to get one of those on-board loop temp gauges by traxxas that i can just wrap round the motor? do those work well?
top speed was around 45-50mph with 22/65 gearing.

heres the thing im concerned about. This time, i ran the truck till the LVC cut in. The MMM stops the trottle when i try to accelerate, so i figured this was the LVC. no sounds or lights or anything, just throttle interuption.
anyway, so i stop running and hook my lipos up to my hyperion. i have the custom LVC set to 19.2v, thats 3.2v per cell just to be safe. I look at the first lipo, and sure enough each cell is about 3.2-3.3v. all is good. i look at the second lipo, and two of the cells are 3.2v, but one of them is 3.0v?? whats up with that? Technically the MMM LVC should have cut in sooner because the overall pack voltage would have been lower than what i programed it to cut off at. I am a little concerned now... not too concerned though. 3.0v is still ok right?

What i think i'll do now is charge both lipos up to 60% because i wont be driving it for a few days.

[George16]

3.0V is still okay and so was your temp of 120F.

[suicideneil]

By handheld temp gauage you mean an IR heat gun (the type you point at an object then press a button to get a reading)? Dont be affraid to stop for a minute or two to take off the shell and get good temp readings (I have a whacking great big hole in the rear of my shell for said purpose). Dont be too worried about the cell voltages being slighly uneven either, I get the same thing with my A123s and zippy lipos; the safest minimum voltage for lipos is about 2.6-2.8v per cell. You wont get any warning lights or sounds either as the MMM has no way of making sound- the chimes are generated by the the esc pulsing current through the motor at certain frequencies to generate a high pitch buzz, and it cant do that & spin the motor at the same time.

You worry too much...

[ReV:-O]

i know, its not healthy... lol

thanks for that bit of info, but i think you are wrong about the MMM not being able to make sounds. otherwise, when you turn it on, it makes sounds, but the motor does not move.

also what would you say about the on board temp gauge, are they any good?

thanks alot for your help

[suicideneil]

Wrong- how dare you question the word of a BL God!

Disconnect the motor from the esc, then try turning it on- you will suddenly find there is no noise at all. The motor doesnt need to spin to make the chimes, its the frequency of the current through the windings that generates a sound- its not done in a way that makes the motor want to spin. Trust me, or just ask BrianG etc.

Anyway, the onboard temp gauges with loops look pretty good, you just have to find a way to keep the loop around the motor (a finned can would be handy), and then you can monitor the temp at the push of a button, and record maximum temps etc with different gearing. Wouldnt like to recommend a specific brand, but Im sure a little searching around will yield answers- they are normally used on nitro engines, so thats a good starting point.

[BrianG]

Neil is right (that actually caused me physical pain to say! ). The motor doesn't turn. The ESC is probably sending pulses to two opposing phases at once to keep it from moving. However, I have seen the motor move slightly when it beeps, but it seems to depend on where the rotor is sitting at the time.

[ReV:-O]

o right lol i surrender to your r/c knowledge! i think i will grab myself one of those on board temp guages, they seem pretty nifty