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rockford
04-17-2013, 10:05 PM
so im just curious about what other ppl are running in there boats. i have turnigy nano-tech 6500mah 2s2p 50-100c and im just over 3 min of run time and if i get close to 4 min it hits the studder bump. Is that a normal amount of time? i use both the stock prop and a 45x68 also they are hard packs and are ballooning

photohoward1
04-17-2013, 10:11 PM
Need more info. Boat, motor, controller. You wrote you are running 2s2p.. 6500 cells. That's 13000 mah. If you are using your batts in 3 minutes you are running 360 amps!

Heaving Earth
04-17-2013, 10:48 PM
I think 2s2p is how the individual packs are configured, not his esc.

Heaving Earth
04-17-2013, 10:49 PM
I also assume he is running a stock revolt given that this thread is under the revolt forum title

Heaving Earth
04-17-2013, 10:52 PM
Anyways, try not to run to studder bump and prop down for cripes sake. Why sucha big prop? If you want more speed upgrade esc and run 5s.
I can never figure why people try to run honkin ass props on systems that aren't designed for it to gain more speed.

rockford
04-18-2013, 12:04 PM
Yes its just a stock revolt that's why I posted here and I did list that bigger prop but only used it a couple of times I mainly use the stock prop and still getting around the same run times with it. What reasons would it pull that many amps? It's all stock

TristanJones
04-18-2013, 12:33 PM
Need more info. Boat, motor, controller. You wrote you are running 2s2p.. 6500 cells. That's 13000 mah. If you are using your batts in 3 minutes you are running 360 amps!

surely these packs would be in series.... in which case 6500 4s2p, the 3mins sounds about right, however if the packs are puffing then somethings not right. Your packs are rated at well over 300amp constant draw....

ProfileBroKen
04-18-2013, 04:21 PM
My stock revolt with a 42X1.4 graupner composit prop was getting 6+ minutes (34ish mph) on 5000mah packs. With a 45X1.4 cnc aluminum prop, I am getting 4 minutes of run time (40ish mph). With a badly sharpened/balanced octura M545 prop, I get about 3.5 minutes (44ish mph). The 45mm prop setups come back fairly warm (batteries, motor, and esc). No puffed packs. Using Gen Ace hardcase 40C and 50C 2 cell packs in series.

I put some eagletree readings on another thread if you want to see details.

photohoward1
04-18-2013, 05:49 PM
Maybe they are bad Chinese cells..

Chilli
04-18-2013, 06:10 PM
First lets make sure we are all getting the nomenclature right. If you are running two 2S packs in series which I believe is the proper set up for the Revolt, that is 4S1P. I believe the stock prop is a 42x55. With the prop you are running, three minutes sounds about right. The faster you go, the more amps you burn and the shorter the run times. If you run the packs to low voltage cut off, you will hurt them and they will puff.

rockford
04-18-2013, 06:33 PM
i want to say one thing they are 5600mah not 6500mah my mistake

Niky
04-20-2013, 08:43 AM
Hi Guys,
I'm planing to buy the Revolt 30, I had the Spartan and nothing went good with that boat.
So i wanted to know if the Revolt had some important problems?
Looking trough the post on this forum, seems that Revolt is reliable unlike the Spartan.
And the other question is;
what about running the Revolt on 6s? Because of my Spartan I had to buy just 6s batt.,now i would like to use it also with Rev.
Is it enough just to change the esc, to put one T180 esc and leave the stock motor?
I heard that the T180 esc is OK even with 1800kv motor despite the 1600kv motor is better, possibly...
Thanks, salute all Niky.

BHChieftain
04-20-2013, 09:56 AM
Hi,
If you are looking for a reliable boat, then you will want the RPMs in the 26,000-32,000 range IMHO, which is either the stock setup on 4S1P (with the 1800kv motor you are at 26K RPM), or on 6S you would need the bigger ESC and a 1500kv motor (32K RPM). Note, a 1600kv motor on 6S would put you at 35K rpm, on high side but probably ok.

6S on 1800kv is 40K which IMHO is too high for a reliable setup but if you are sure your boat is setup correctly and your driveline/prop are perfectly balanced it would be a speed demon... just more to go wrong at that RPM.

The stock AQ ESC is a really nice and highly water resistant ESC--- you might be better off buying new lipos (two 2S1P packs) vs. buying a new ESC. You can probably resell your 6S packs here on the swap shop. But it depends on what you are trying to accomplish-- a reliable fun runner, or a rocket (with potentially a short lifespan!)

Chief

Niky
04-20-2013, 12:33 PM
Hi Chief,
thank you for your observations, but i'd like to know did the Revolt have its "own" problems as Spartan have, eg.: burning the ESC, slipping the collet driver, behavior on the water?
The RPMs you've reporting can be regolated by changening motors with their ESCs.
Thanks again, salute all Niky.

Heaving Earth
04-20-2013, 12:37 PM
I think the revolt only had minor issues on "some" of the boats such as poor motor alignment to flex shaft (easy fix ) and maybe decals not stuck on great, but from my knowledge there were no esc motor issues or any problems that couldn't be fixed on the spot, without need for new parts.

BHChieftain
04-20-2013, 03:59 PM
On the power system side-- the aquacraft motors and ESCs have a great rep, and they are frequently used as power systems for p-spec limited classes (but usually the UL1 2030kv motor + 60A marine ESC). I use it in my woodstuff 29" OPC racing tunnel, and will be going into my p-spec limited hyro (hull under construction now by Randy at BBY racing!)

Chief

rockford
04-20-2013, 10:39 PM
Hi Chief,
thank you for your observations, but i'd like to know did the Revolt have its "own" problems as Spartan have, eg.: burning the ESC, slipping the collet driver, behavior on the water?
The RPMs you've reporting can be regolated by changening motors with their ESCs.
Thanks again, salute all Niky.
i have not had any problems with my boat and as far as water resistance and driving problems it seems preety solid on the water, I have a futaba setup and cannot comment on the stock radio but i was running my boat the other day and it hit a wave wrong and the lid blew off and was nose up and it took 20-30 min before i was able to get it back to shore with my villain but the esc was still working but servo and receiver didn't so i put it in rice over night and was good to go. if your thinking of a revolt i really like mine my only complaint is basically this post 3 min of run time on two batteries is kinda gay im used to my race trucks where a single battery is around 7 min or so and my buggy is like 15 or so. But overall seems like a good boat exept the battery tray is chinsy and tears easily so that will be the next upgrade along with either a balloon or traxxas water proof receiver cover and waterproof servo

Bduncan
04-28-2013, 11:37 AM
Here is revolt with 180amp esc stock motor 5s 5450mah 120c pack. Prather 220. 6s is too much for revolt.
https://www.dropbox.com/s/fnh90v5wuuv9lmk/20130303_170852.mp4

jstolz
04-28-2013, 09:25 PM
I suspect that by running the boat for too long of a time you have damaged the batteries. Puffing the batteries is a condition of abuse. Boats draws lots of amps compared to cars. So, your car will run a lot longer with similar capacity batteries. Running the Revolt on a 5600mah battery for 4 minutes is really pushing the battery too much. You want to have about 20 to 25 percent left in the battery to have it last. You don't want to run the boat to voltage cutoff. If you do the battery could be damaged.

BHChieftain
04-29-2013, 10:01 AM
Rockford--
Monos have a lot of hull in the water, so it takes a lot of energy to push them. The big plus of monos is you can run them in a lot of chop and also on windy days.

If you want a boat with longer runtimes, consider a Cat for your next boat. This type of hull requries less energy to push thru the water. My son gets over 5min of runtime on his 5000mah hyperion packs using a speedy x642 prop on his stock Miss Geico. On a slower prop he can get over 6min.

Downside of the cat vs. mono-- cats hate wind... note, they still run pretty well in light chop, but not really big chop.

Chief

Bduncan
05-02-2013, 07:58 AM
I have no problems running my revolt on a good 6000mah 4s for 8 minutes. Dual water pick ups. Separately cooling esc and motor. 42 55 grim

Bduncan
05-02-2013, 08:07 AM
I have a revolt and a spartan. The spartan is an ok boat but by the time you add the mods that make it a better boat you may as well purchase a rtr 35 inch mono fiberglass hull set up. My revolt is etremely fast on 5s (180 amps esc). It runs close to the edge on 5s. You would likely needs to run two 6000 mah 3s in series for a 6s set up. I wouldnt do it. I suspect you could pull full throttle for a second or two before the boat gets too loose. Also, the added weight of two packs is just not worth it when the boat is extremely fast on 1 5s pack. If you flip the boat you the batteries are likely to knock open the hatch. The revolt hatch is quite difficult to latch down. When I started running a boats I would heavily modify them to make them faster often powering them beyond design limits only to figure out I should have built a custom boat tht is reliable.

metoo
05-20-2013, 03:42 PM
You don't want to run the boat to voltage cutoff. If you do the battery could be damaged.

Isn't the whole point of LVC to protect your battery? What is the factory LVC set at? I assume it's not programmable, right? I've never had an issue running my cars to LVC, but then again, I can set the voltage at which that occurs, with exception of my Traxxas 1/16 Rally VXL.

metoo
05-21-2013, 09:50 AM
Isn't the whole point of LVC to protect your battery? What is the factory LVC set at? I assume it's not programmable, right? I've never had an issue running my cars to LVC, but then again, I can set the voltage at which that occurs, with exception of my Traxxas 1/16 Rally VXL.

Ooooh, I see now that Aquacraft has a terrible setting for the LVC. According to the manual, you should notice a "stutter bump" in the performance when you hit 12V [which is already too low at 3.0V/cell]. Then there is conflicting information. The manual says, "Low Voltage Cutoff: 11.6V " and "It also has a 10.8V battery cut off safety system that shuts the power down to the motor to avoid damaging the batteries." Either way, guess what. You're already in damage zone at that point.

I need to find one of THESE (http://www.hobbypartz.com/libaprforcar.html), but for 4S and adjustable. If not adjustable, with a more reasonable 3.3V/cell 50% cut-off, so that I can still get the boat back to me. If you know of one, please chime in. I prefer not to sell the original ESC.

Heaving Earth
05-24-2013, 10:56 PM
Ooooh, I see now that Aquacraft has a terrible setting for the LVC. According to the manual, you should notice a "stutter bump" in the performance when you hit 12V [which is already too low at 3.0V/cell]. Then there is conflicting information. The manual says, "Low Voltage Cutoff: 11.6V " and "It also has a 10.8V battery cut off safety system that shuts the power down to the motor to avoid damaging the batteries." Either way, guess what. You're already in damage zone at that point.

I need to find one of THESE (http://www.hobbypartz.com/libaprforcar.html), but for 4S and adjustable. If not adjustable, with a more reasonable 3.3V/cell 50% cut-off, so that I can still get the boat back to me. If you know of one, please chime in. I prefer not to sell the original ESC.

The batteries drop lower when they're under load (motor spinning prop in water). When it hits lvc, then bring it in and check your batteries, they will be above 3.0v per cell.

BHChieftain
05-25-2013, 01:45 AM
I don't think voltage is a reliable way to measure the remaining pack capacity. Lipos should be targeted to keep 20% capacity in reserve, dipping into this range risks damaging the packs. If folks are running until they hit the AQ LVC, I'd think about checking how many MAH are put back into the packs to see how far down they are really running the packs.

Chief

Evesniper
06-20-2013, 07:11 PM
Isn't the whole point of LVC to protect your battery? What is the factory LVC set at? I assume it's not programmable, right? I've never had an issue running my cars to LVC, but then again, I can set the voltage at which that occurs, with exception of my Traxxas 1/16 Rally VXL.

LVC is the absolute minimum a LIpO can go, before dmg occurs the the cell(s).
SO the LESS you run A LiPo down. The better. Even with high end LiPo's

rockford
06-24-2013, 10:14 PM
so let me get on the same page if you want to leave 20-25% left then lets say my packs are 5600 i should be able to use 4200 mah and should be around 3 1/2 min, this is calculating off of my boat yesterday running 2 min and charging about 1200 mah back into each pack. fyi my boat is all stock sometimes i run a 45x68 prop which keeps it at a decent speed for now

BHChieftain
06-24-2013, 11:41 PM
I target 15%-20% myself
Chief

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