No LVC for Mtroniks Truck

[tcolesen]

Many of us have seen the LVC feature on the programming for the Mtroniks Truck controller. Yesterday and today I have been doing some rather extensive testing trying to see the voltage per cell that it will cut off at (Lipo). Well, even when set at 4s Lipo in programming, the motor was allowed to spin at the full input voltage of 5v! The motor should not be allowed to spin any lower than 12v for 4s Lipo. This can be rather dangerous, and in use I have noticed my 3s Lipo actually drop its voltage low (motor was hardly spinning), but fortunately no problems came out of it. I suppose this could be easily fixed with a newer software version, but I have v1.05.

Anyone have a similar problem that they have noticed or could test?

[glassdoctor]

I'm sure you weren't actually using a 4s lipo when testing at 5v.... ;)

Sounds like the LVC doesn't work at all... unless there is something in the software that allows it to overide the "4s lithium" setting when you connect a much lower voltage source, like a 2s lipo for example. Something like an auto-voltage sensing feature. Is it possible that's what happened? Probably not, huh?

This is unfortunate... a non-functioning LVC can have costly and dangerous consequences.

[tcolesen]

You're right, I wasn't testing a 4s Lipo at 5v. But the fact that the motor was allowed to spin when set like that is bad. With 3s Lipo, the LVC wouldn't kick in when voltage got down to 9v. Even with 2s, it wouldn't cut out at 6v or even 5v (this was done by my ICE's variable voltage motor run-in thing).

Looks like I'll be using my MGM Compro 120 for Lipo applications (that I finally got back after 6 months!). I tested that, and it cuts the motor at 3.1v/cell! That is very good.

[Muck]

Wow, I didn't know the ICE could be used to test that way. I could swear that my uf-75 doesn't cut out when it should. I just stop runnig when I feel a voltage drop. I'll have to test it out. How do you hook it up and test?

[Key]

I'm curious to see what type of results may be expected when upgrading the firmware. I think it won't hurt getting a second opinion from mtroniks regarding testing with v.1.05

[tcolesen]

Treat the ICE as if it were a battery. I hook up a motor in parallel with the controller, just so there is a load when it starts up. If the ICE doesn't find a load on its output, then it will say that the motor is disconnected and it will stop. After it gets up to the selected voltage, then I plug the controller in. It is important to spin the motor on the controller without a load, as the ICE can only handle 10amps continuous on the motor run-in feature. It can only go up to 8volts, so you can really only test a 2s Lipo.

[chilledoutuk]

hmm i suspected this as my mtroniks sport allowed my lipo 2s to get down to about 5v which anoyed me as i didnt want the cells going any lower than 6v.
Has anyone had any response from the mtroniks guys about this ?
I would be interested if a much newer firmware would improve the LVC.

[tcolesen]

I'll email Mtroniks about this later, and hope for an informative response.

[Rtsbasic]

I'll give them a ring tuesday (next working day in the UK) and ask them about this, as its quite important to a lot of people I'd imagine.