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Can a Battery Ruin an ESC?

Can a Battery Ruin an ESC?

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Old 06-23-2011, 11:03 AM
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the only way i see that a battery could blow a esc up is if you go over the voltage that the manf tells you and you use a battery that is over the voltage or to many cells.

r40: i get what your saying i tried a 4c 25c and a 4c 30 and 35c on my 1/8 truggy and it will work and have good power but its not as efficent and does tend to get all your electrics to get warmer. i tried out a 4c 5000mah 50c omg big diffrence in power all around and its more effiecent and did run a bit cooler.
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Old 06-23-2011, 11:27 AM
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Originally Posted by tc5 man View Post
the only way i see that a battery could blow a esc up is if you go over the voltage that the manf tells you and you use a battery that is over the voltage or to many cells.

r40: i get what your saying i tried a 4c 25c and a 4c 30 and 35c on my 1/8 truggy and it will work and have good power but its not as efficent and does tend to get all your electrics to get warmer. i tried out a 4c 5000mah 50c omg big diffrence in power all around and its more effiecent and did run a bit cooler.
What you saw is a lack of Voltage Sag. Sag is when the voltage dips way below nominal under load. As voltage goes down, amps go up and the temperature with it. That's why they are able to get away with telling people that anything short of a high quality battery "Hurts" the ESC.

The thing is, I've seen people fry ESCs with their driving technique(and yes, even WITH a "High Quality" battery). They are convinced the only way to get around the track is by blipping the throttle, like a nitro. I tell them they suffer from "Nitro Finger". By blipping the throttle they are nailing the electronics with amp spikes. Initially, this is what I thought the ESC companies were referring to as "Ripple Current". The actual claim was, that even with smooth throttle inputs the battery would send Magical Mystical uneven "Waves" of energy that would destroy the FETs and let the magic smoke out... I call BS! I think most of the failures are due to one of two things. User Error and/or Manufacturing Flaws.
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Old 06-23-2011, 11:42 AM
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Originally Posted by R40Victim View Post
What you saw is a lack of Voltage Sag. Sag is when the voltage dips way below nominal under load. As voltage goes down, amps go up and the temperature with it. That's why they are able to get away with telling people that anything short of a high quality battery "Hurts" the ESC.

The thing is, I've seen people fry ESCs with their driving technique(and yes, even WITH a "High Quality" battery). They are convinced the only way to get around the track is by blipping the throttle, like a nitro. I tell them they suffer from "Nitro Finger". By blipping the throttle they are nailing the electronics with amp spikes. Initially, this is what I thought the ESC companies were referring to as "Ripple Current". The actual claim was, that even with smooth throttle inputs the battery would send Magical Mystical uneven "Waves" of energy that would destroy the FETs and let the magic smoke out... I call BS! I think most of the failures are due to one of two things. User Error and/or Manufacturing Flaws.

You said it yourself, voltage sag. Amps=heat, heat=resistance and electronics don't like heat, we all know that. Cheap batteries give out under load and are just unstable, which is where the problems come from. Ripple current is what it is and it's hard on electronics.
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Old 06-23-2011, 11:54 AM
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Originally Posted by R40Victim View Post
What you saw is a lack of Voltage Sag. Sag is when the voltage dips way below nominal under load. As voltage goes down, amps go up and the temperature with it. That's why they are able to get away with telling people that anything short of a high quality battery "Hurts" the ESC.

The thing is, I've seen people fry ESCs with their driving technique(and yes, even WITH a "High Quality" battery). They are convinced the only way to get around the track is by blipping the throttle, like a nitro. I tell them they suffer from "Nitro Finger". By blipping the throttle they are nailing the electronics with amp spikes. Initially, this is what I thought the ESC companies were referring to as "Ripple Current". The actual claim was, that even with smooth throttle inputs the battery would send Magical Mystical uneven "Waves" of energy that would destroy the FETs and let the magic smoke out... I call BS! I think most of the failures are due to one of two things. User Error and/or Manufacturing Flaws.





yea i see what you mean it dint blow up at least it was only 5 min heats though but im buying at least 40c 4c batterys though and no $100 lipos ethier ! lol yea you cant drive a high power electric with a nitro finger thats a fact your asking for extreme heat .

thats usaully guys who never driven a electric that does that.
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Old 06-23-2011, 12:31 PM
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Originally Posted by [email protected] View Post
You said it yourself, voltage sag. Amps=heat, heat=resistance and electronics don't like heat, we all know that. Cheap batteries give out under load and are just unstable, which is where the problems come from. Ripple current is what it is and it's hard on electronics.
Oh, so my 20C cheap "Low Quality" battery that I used for 3 years was a Fluke? A slight increase in heat does NOT equate to a failed ESC. My system rarely exceeded 140F, that's both the ESC and motor.

I've seen people with an identical setup fry a system with a combo of "Nitro Finger" and poor soldering. Most of the ESCs I've seen fail, were due to poor construction or user error.

"Ripple Current" is an internet myth bred from companies not wanting to really diagnose what caused a failure. If you tell your customers its their own stupidity that fried the thing, you'll lose customers. If you tell them they bought a "Sub-Standard" battery then they blame themselves and buy another ESC. Its part of why this hobby can be tough to expand. If you tell somebody they have to spend $180+ on a single battery, they'll go back to video games. If you tell them they can do the same thing with a $50 battery, they seem allot more interested.

thats usaully guys who never driven a electric that does that.
There are a few drivers I know that drive that way... even though the bulk of their racing experience is electric.
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Old 06-23-2011, 12:42 PM
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Originally Posted by R40Victim View Post
Oh, so my 20C cheap "Low Quality" battery that I used for 3 years was a Fluke? A slight increase in heat does NOT equate to a failed ESC. My system rarely exceeded 140F, that's both the ESC and motor.

I've seen people with an identical setup fry a system with a combo of "Nitro Finger" and poor soldering. Most of the ESCs I've seen fail, were due to poor construction or user error.

"Ripple Current" is an internet myth bred from companies not wanting to really diagnose what caused a failure. If you tell your customers its their own stupidity that fried the thing, you'll lose customers. If you tell them they bought a "Sub-Standard" battery then they blame themselves and buy another ESC. Its part of why this hobby can be tough to expand. If you tell somebody they have to spend $180+ on a single battery, they'll go back to video games. If you tell them they can do the same thing with a $50 battery, they seem allot more interested.



There are a few drivers I know that drive that way... even though the bulk of their racing experience is electric.



wheelspin city driving that way

im smooth on the throttle but a little hard on it could be smoother though so everything stays cooler but its a truggy you cant help it its just begging to be drove hard.
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Old 06-23-2011, 12:43 PM
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Originally Posted by R40Victim View Post
Oh, so my 20C cheap "Low Quality" battery that I used for 3 years was a Fluke? A slight increase in heat does NOT equate to a failed ESC. My system rarely exceeded 140F, that's both the ESC and motor.

I've seen people with an identical setup fry a system with a combo of "Nitro Finger" and poor soldering. Most of the ESCs I've seen fail, were due to poor construction or user error.

"Ripple Current" is an internet myth bred from companies not wanting to really diagnose what caused a failure. If you tell your customers its their own stupidity that fried the thing, you'll lose customers. If you tell them they bought a "Sub-Standard" battery then they blame themselves and buy another ESC. Its part of why this hobby can be tough to expand. If you tell somebody they have to spend $180+ on a single battery, they'll go back to video games. If you tell them they can do the same thing with a $50 battery, they seem allot more interested.



There are a few drivers I know that drive that way... even though the bulk of their racing experience is electric.
I never mentioned C rating, normally a low C battery will just puff itself from the motor asking too much of it. I meant cheap as in cheaply made, ie. lots of internal resistance in a bad pack. Even the big guys have some bad ones here and there, it happens. Just because it has a cheap pricetag doesn't mean it will ruin the ESC.

Batteries are a great powersource to steadily draw from, but we're all over the place in what we ask from a battery on any given track and ripple current is just a natural occurence with this type of electronic usage. A pack with a higher resistance is going to deliver power late when asked, then overshoot, flatten back out and undershoot when it shuts off late, creating the ripple.

I've got $10 Lipos in my jetboat and they work great for that application, not all budget batteries are bad.
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Old 06-23-2011, 01:52 PM
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To simply spec a certain C rating as a guideline is simply asinine. My Checkpoint 5400 16c pack can put out over double the amps as my Reedy 2400 25c pack. By some companies' claims, if their esc blows up with said Checkpoint pack, they will call it the cause, but won't call the Reedy pack as the cause of a failure. Maybe companies should start setting a benchmark of total amperage (say, 65 amps continuous).

I've run my LRP esc's on every battery under the sun, from a Shark 1500 Ni-Cd pack to the best 60c lipos out there and never had a failure that was unexplained (I plugged a few in backwards - all my fault) due to an "insufficient battery."
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Old 06-23-2011, 08:51 PM
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I have a Mugen MBX5T-E with a Leopard 1600kv 4082mm running on 6s 5ah 30c zippy's, it's geared for 69kph (probably about 45mph or so?).

I also have the Turnigy watt meter, and the PEAK/BURST that thing shows is 93A (@ 22.66v), that's the highest I have ever seen it.
Continuous would be much much lower.
I have it all running through the 150A XeRun ESC, I think I could have gotten away with the 80A.


I too think this ripple current thing is a load of crap, the problem (if any) would be a low quality cell with a high resistance that can't take the shunt from regenerative braking, virtually bottle necking it.
Even this I don't think is a major problem, as others said, brushless systems ran fine on NIMH for ages.
EDIT: I agree that voltage droop is also something worth mentioning, my system when I had the watt meter on it recored a lowest voltage of 20.66v (down from 22.66v).

I'm not some whiz bang electrical genius but this is what I think.
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Old 06-23-2011, 09:09 PM
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Ripple voltage is not a myth... I hope this analogy makes since...

Take something like a firehouse with a nozzle(bad solder joint/bad cell in the batt/etc) at the end, when its spraying water everything is fine, when you turn off the source(let off the throttle) there is still some pressure(voltage) for a few seconds(much less in an esc, but you get the point) before the water stops flowing. Now add pressure going from the other way(regen brakes) and the pressure skyrockets.


I have eagletree graphs of a 1/8 Losi brushless system had the voltage spikes ABOVE the peak voltage that the packs started out at. A few races later the ESC died...
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