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romulus22 wrote:What size are the batteries. The problem I was told that most likely was wrong with mine is that the batteries couldn't keep up with the amp draw of the ESC.

my thoughts exactly (assuming the esc isn't disfunctional). Size matters (it always does, regardless of what they say ) but the age of the lipo. the way it's been treated, and so on matter just as much.

A battered 5000mah 50C will pump out less amps than a fresh 2500mah 50C...

Most LVC issues I've seen on "competition grade" speedoes were due to worn-out batts.

Then again I dunno about TRX's

Paul

Lonestar wrote:

romulus22 wrote:...the batteries couldn't keep up with the amp draw of the ESC.

my thoughts exactly...

On the topic of amp draw:
The Traxxas VXL ESC has a 200 amp (!) rating, which is pretty high!
The Hobbywing ESC's that are so popular come in 30A, 60A, maybe up to 120A,
while the VXL is 200A...

I get it about the amps but I don't get how it all of the sudden theesc. worked that one time right after I changed the battery end. Maybe the heat from the soldering gun traveling threw the wire to the circut board did something to make the esc work. I remember removing a instrument cluter from a 98 Dode Caravan and having to resolder bad connections on the crcut board to make the speedo work. Also PS3's have th same problem with there circut boards. With those you use a heat gun over the board melting the solder back to the board. I have a 6000 2cell lipo I'm going to try.

It doesn't seem to me like trying out yet another battery will prove anything, or address the issues as described even in the last 2 or 3 posts. Don't you have another ESC you can try? Keeping on testing different batteries when either a faulty ESC, badly-soldered ESC, ESC with wonky connectors, ESC with low-voltage detection issues, etc. are possible culprits seems like banging your head repeatedly against a wall, to me...

Um, I do but thats not the point. I'm trying to figure out whats wrong with this esc. That was kind of the point of the post.

Anyways, I have to put the truck on the back burner. I got that Jato in yesterday and an RC-10 buggy turned into a truck today so I have to move along. I'm going to start a thread about the buggy in the RC-10T section before I part it out. My nemesis Traxxas just won't leave me alone. Talk about the in your face irony of it all. Maybe I'll just call it a day and put this esc in the Stampy with an old stinger. Then I'll hook it up to the lipo and take it out for a spin. I predict fire.

K-TOWN-KITT wrote:Um, I do but thats not the point. I'm trying to figure out whats wrong with this esc. That was kind of the point of the post.

Not to pick, but I don't see how changing to a battery with the same voltage rating/longer run capacity will help you determine what's wrong with the ESC, as the issue seems to be due to low voltage features programmed into the ESC. Anyway, I predict: It'll run a while longer, then cut out again.

if it is going into low voltage cutoff, then it's due to the input wiring you have and here is why:

apparently, the lvc circuit is very 'fast', that is, once that threshold is crossed, even for a split second, the esc shuts down. usually that circuit will have some filtering on it where a short 'blip' below the threshold won't trigger the lvc, but a sustained drop in voltage will cause it to cut out. hearing that they have a problem with the lvc, I would say this is likely, and you might want to inspect the circuit board inside(if possible) for any cold solder joints.

secondly, all it take is fractions of 1 ohm on the input wires to make the esc 'see' less than the threshold and cause it to go into lvc, take this as an example:

if you were able to pull 1 amp through 1 ohm of wire, you would drop 1v from the source voltage. on a throttle stab, you will likely pull upwards of 50 amps for a split second, if you had .02 ohms of resistance in either wire, you would lose 1v across that connection and hit your lvc.

so double and triple check all your connectors and solder joints, it looks like you are using sermos/powerpole type connectors that have silver plated contacts that corrode very easily. I have burned up sets of those connectors as they aged.

Just put a new Traxxas end on both the battery and esc. Same as usuall. Gets up to speed and cuts out. I then changed the esc from lipo to ni-mh. the truck ran great for about 8 mnutes then started to slow a little so I just stopped running it. Changed the pack with another and beat the hell out of the truck for just about the same time. 8 minutes. Truck ran fine and took all of it. So it's gotta be the lvc. That stinks. Cold solder joint. Those were the words I couldn't think of. Tank you.

dldiaz wrote:

Lonestar wrote:

romulus22 wrote:...the batteries couldn't keep up with the amp draw of the ESC.

my thoughts exactly...

On the topic of amp draw:
The Traxxas VXL ESC has a 200 amp (!) rating, which is pretty high!
The Hobbywing ESC's that are so popular come in 30A, 60A, maybe up to 120A,
while the VXL is 200A...

so the traxxas MUST be better, right

Wish you guys would of just said " Look dummy your old puffy lipos suck. Buy some new ones cheap skate." I'm doing the math. 5000 2s 20c=200 amps right. Ok had pack 2 1/2 years. About 9 months ago I started screaming my 2WD SC-10 with a Novak 10.5 and a Tekin RS at 100% with no fans. Esc and motor reach 200+ and the puffy pack reaches 140. 20+ minute runs. All the time! When the truck started to slow down, I unhooked the pack, let it cool and recharged it. So your saying afer all that abuse, the pack might not be in the best condition and just not be able to run the esc? Feels like a fool. Going to find me one of those 11.1's and a new body. When will you stop cursing me Traxxas? Bought this body for $29. shipped for a pede dude backed out on. Kept the body for 6 months. Just sold it on Oct. 15th. Found this Nov. 4th. Not to mention I sold a brand new Trungy 11.1 for $30. like 2 months ago.
http://www.ebay.com/itm/380739512916?ssPageName=STRK:MESOX:IT&_trksid=p3984.m1561.l2649#ht_210wt_1133

" Look dummy your old puffy lipos suck. Buy some new ones cheap skate."

just sayin...

Todd

ps

K-TOWN-KITT wrote: Ok had pack 2 1/2 years.

Not sure why but I can't stop laughing!