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Issues with My VH Slick

6K views 51 replies 21 participants last post by  JAG 
#1 ·
I've got an issue with my VH Slick. This started happening at Nash. When flying, I the motor will spool up to full speed, then get slower and lose power. I have tried all my batteries. I thought it was a broken motor lead at the bullet, but I re-soldered them all. Watch the video below to hear what its doing. Is is full throttle, I am not pulling back on the stick.

Any ideas?

 
#28 ·
allen said:
That's not typical. Mine have at least a hundred cycles each.
Yeah that's what I was thinking. I think I take pretty good care of them. I don't take them to storage charge after every use, but if they sit for longer than a few days I will take them to storage charge. I track my usage on a phone app, so I know exactly how many cycles I have one each pack. Very frustrating to only get 25 out of a pack before they start to sag. None of them are puffed either. I only use them on this plane.
 
#34 ·
Yeah it sucks since all 5 went bad right there together. I ordered a battery from ReadyMadeRC today to try, but wont know for awhile how it holds up

I'll have to pick up some of those Turnigy ones as well. I flew it with a 800mah over the weekend and it flew great with that too, so I may get a few in that range as well.
 
#35 ·
JAG said:
Motor: GForce 2206-1500kv
ESC: Hobbywing FlyFun 12A
Prop: Gemfan 8x4

This is the recommended setup from Value Hobby for this plane.
Ok, so this ESC would not even let you to program cut off voltage...

If you get this little battery checker(see link below), it will display energy in your battery in a "fuel gauge" style as well as percentage after you finish flying, and if your ESC does not cut off, and you routinely lending with less then 20% left in your battery, then reprogram your ESC to medium cut off, and if that doesn't work, then high. Going with a higher capacity(if your wing loading let you, is a good idea), as well as higher battery "C" rating.

https://hobbyking.com/en_us/cellmaster- ... ecker.html
 
#37 ·
JAG said:
Well the issues was not the ESC. Come to find out it is the batteries. They all have an average of around 25 cycles on them.

This is the battery they are : http://www.valuehobby.com/30c-500mah-3s-jst.html

What is typical as far as cycle count on a battery?
I've had some of those batteries fade out too. The loss of power seems to be more related to the age of the battery than how many charge cycles. Mine only lasted about a year and an half before the top end power faded away, even though the checker still showed them to be fully charged.
 
#38 ·
JAG said:
I don't have one of those but I do check my voltages. I use a timer and never drain them below 11.1 volts. I also balence charge every time I charge. Usually no faster than 1C.
Slow charging is good. However 11.1 volts per battery(or 3.7 volts per cell) is actually a nominal(operational) voltage. Cut off voltage should be no lower 3.2 per cell, or if to be on safe side 3.3 volts. Your ESC see combined voltage, so cut of 9.6 to 9.9volts, and most ESCs will do it by default(factory) settings.

Though I agree with McDDD that self life is important for battery ability to store energy, but if even on a new battery voltage was dropped to 3.0 volts or below(and it only takes one cell) that battery capacity pretty much just been decreased by 1/3 or even half of its capacity.

As for timer, well I've seen a very good programming on DHooks radio where he had throttle channel actively progressive timer where once above half throttle timer ticks at normal rate, and once below half throttle then it's twice slower, but it is hardly a substitute for telemetry and programming a proper cut off voltage is still a must. Get that little battery checker and see the condition of your battery after every flight, other wise you kinda blind when it comes to what is your battery condition is.
 
#39 ·
It's actually completely proportional, full stick 1 to one, anything less is that percentage.

If I set my timer at 2 min 30 second for example but have my throttle at 1/4 the entire flight it will take 10 min to count down to zero, but if it's at wot for the entire flight it goes off at 2 min 30 seconds.

Real world flying it gets me about 5 min of actual flight time on most of my setups.

Like BB said it's not perfect as you have more losses to heat etc at higher throttle settings so that throws it off, but it's a great safety net if set up correctly.

On a slab it's fairly easy to get your normal countdown timer set right , but something like the senourita I had didn't really work at all, if you were cruising around getting your inner CJ on you can fly 10/12 min, but if your down hovering and yanking it around you might get 4 or 5 min.

Ersky9x is awsome, but I know a $35 radio is to pricey for most of you :)
 
#41 ·
McDDD said:
JAG said:
Well the issues was not the ESC. Come to find out it is the batteries. They all have an average of around 25 cycles on them.

This is the battery they are : http://www.valuehobby.com/30c-500mah-3s-jst.html

What is typical as far as cycle count on a battery?
I've had some of those batteries fade out too. The loss of power seems to be more related to the age of the battery than how many charge cycles. Mine only lasted about a year and an half before the top end power faded away, even though the checker still showed them to be fully charged.
I think I just got a crappy batch of batteries. These didn't even last a flying season. I have over 140 flights on my VH slick, but that is between the 5 packs.
 
#42 ·
As far as my timer, I set it for worst case and flip the switch when I take off. Like I said it is never below 11.1 when I land and it settles out. Its usually higher than that. I'm not one to fly until the power is gone like most of the guys at the field I see. I think I take very good care of my packs. I have some 3s 2200's that I have had for 3 years with a crazy number of cycles on them and they are still pulling strong.

I think this may have been a bad batch.
 
#43 ·
11.1 is good,

Flying till you lose power drives me nuts, and destroys packs.

I've not been overly impressed with gforce bats in general, ir tend to be iffy and overated mAh. And I had a batch of 3 that lasted maybe 25cycles

I know a lot of ppl here love them for the weight but weight for a given mAh usually equals more durability
 
#44 ·
JAG said:
As far as my timer, I set it for worst case and flip the switch when I take off. Like I said it is never below 11.1 when I land and it settles out.

I think this may have been a bad batch.
Here is the "thing" about 11.1 volts - it's actually equates to full charge. You are most likely already discharged your individual cell much lower without knowing it. Low discharge rate battery might rebound back to almost a full charge because chemical reaction happens so slow, while on high discharge rate batts once it's gone flat it will stay flat. So the only way to see what happening to low discharge battery is to measure each individual cell real time and under load(with the motor running), and not some time later after it had a chance to recover. Bottom line ideally telemetry will monitor and alarm each individual cell, without it proper cut off voltage is the next best thing, but like I mentioned ESC is a combined voltage, and if battery pack is unbalanced(where in one cell is significantly weaker then the rest of the cells in the pack) you will still be ruining it down without been aware of it.
 
#49 ·
smallfly said:
How about the glacier's from buddyrc they any good
there are a couple LONG threads on RCG in the battery/charger forum, and while researching some new 6S packs, I found some info about the "branding" of some of the packs. According to the thread, Gens Ace/Tattu, Pulse, and Glaciers are all manufactured by the same factory. There was info on other brands too, but that one caught my eye. Not sure the accuracy of the claim, but it was a well-documented testing thread of large 6S packs that the EDF jet guys were testing/using. My personal experience has been that the Gens Ace 25C rated batteries were very good, and I've heard good things about the Glaciers too. Both of these, for the price point, are quite good. The ones that were best-rated on that thread, however, are the Turnigy Graphenes, at least in larger sizes (they said small, sub 1500-ish Graphenes weren't any better than others). The Graphenes were on par or outperforming much higher-dollar packs, FWIW
 
#50 ·
I have Glaciers and VH Elites. I like them both a lot.
 
#51 ·
JAG why do you have your timer on a switch? You can set it to your throttle and is the better choice because then you don't have to worry about forgetting to activate your timer. That way also with your electric setup if you pull the throttle all the way back to zero the timer stops counting down as well.
 
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