Cornelius

The specs I found claim 0.08A draw at 12V for that fan - see photo. Not very high considering the draw from motors. I doubt this contributed greatly to your reduced runtime.
If possible, try the same test with higher grip & smoother throttle. I think the results of that will tell you more than anything else.

Regarding mamba settings for optimising runtime, anything that requires 'active maintenance' (the ESC actually doing something) will most likely reduce runtime. This will include things like drag brake, punch control, etc.

Cornelius

RCPD make the most complete kit, IMO it is also the best.

Standard gear (from this thread) is pretty much:
Mamba Max Esc (at least one fan)
UBEC (CC BEC is the most common, but can be problematic. I like the SportBEC from dimension engineering)
Neu motor (1512 series for buggy - 1900-3200kv)
Your choice of 4S lipo (preferably rated for at least 100 amps constant)

Some people use different stuff, mainly depending on budget/availability.
A couple of people are also trying the smaller 1509 neu motors, and with new higher voltage ESC's due on the market within a couple of weeks, so a 'standard set-up' is hard to define.

anthonyb711

So can I not use the LRP sphere?

Is the UBEC necessary with all ESC's??? Or am I not understanding what the function of that is?

ffpm46

iTrader: (179)

Thanks Dan, I guess I am just so eager to run my truggy. I just have to wait until the Monster comes out. The additional wait wouldn't have been so bad if I hadn't driven this thing yet.

Will call castle today and see if they are getting close. Thanks for saving me $350.09 + dollars!

lxmuff

I'm not sure that the 4900 size are Enerland cells. They do not show that size on the enerland site.

The Neu 5000 30C cells are enerland.

BTW, there is no reason to drain a $250 lipo down to its limit and damage it for a couple of more minutes of runtime.

happywing

iTrader: (93)

RE: LiPo Voltage Cutoff

I've seen it published from several sources that LiPo are safe down to 2.7v per cell (10.8v for 4s). The 3.0v-per number comes from manufacturers padding the voltage to be safe. Myself, I have run 4s to just under 12v a couple of times. I still have these packs and they are still as good as day one. I avoid going below 12v, but I'm not afraid of it. I set my LVC to 11.5. I have hit cutoff with this setting. By the time I checked the pack it was at 12.6v, even though the cutoff was set at 11.5.
Consider that a draw spike may trigger an LVC cutoff while the pack still has some safely usable power left.
I wouldn't suggest everyone set their LVC below 12v. You must have good cells and keep them balanced.

RobbieS

iTrader: (95)

You CAN NOT use the LRP speedo. It will only support 2S lipo. You will want to run a very minimum of 3S if a buggy (most run 4S) and a minimum of 4S on a truggy.

Depending on what you are converting you can use your currently batteries as long as they have a good c rating. You just run 2 in series to get to a 4S pack. That's what I am doing on my truggy & many others on here have talked about running 2-2S packs instead of a single 4S pack based o the fact that if there is a problem / damage hopefullly only 1 pack takes a hit so replacement is less expensive. I'm doing it because I already own several 2S trakpower packs from 1/10th scale racing.

As for the UBEC on all of the current speedos you will need it if running 4S. As you can see in this thread pretty much everyone used the Mamba Max speedo.

ntm

That's bull.

I'm talking from practical, first hand experience here.
All my ten cell heli batteries are logged for each flight and I keep track of stuff like available capacity, voltage droop for a given amp draw, cycles, etc.
I've got a few hundred cycles on some, and I've had others give up after 50 cycles.
Every single time they've dropped below 3.2 volts per cell, there is a degradation in their ability to hold voltage at a given amp draw.
Doing this repeatedly significantly shortened their life span.
They still work of course, just not as well as a good pack, output and capacity are reduced.
This is with quality enerland cells.

And of course the pack's voltage will come back up once you remove the load, it's sub 3.3 volts under load that does the damage. If a draw spike pulls the cells down under 3 volts, the pack is being damaged, whether you realize it or not.

I wish someone would make a cumulative mah logger that alarms at a user preset value, that would be ideal for these buggies as the loads are quite variable.

Cain

iTrader: (294)

Thanks for the info everyone.

I am going to go ahead and set my cutoff to what Tony uses at 3.3V per cell. I should get some time to test how it performs thursday I am thinking since I will be pulling late nights today and tomorrow, and will be travelin wednesday. Heck, wish I was going to bismarck this weekend, they have no snow on the ground from what I understand.

I'll be calling castle creations over my lunch break to get some info on the Mamba Max ESC, anyone got anything they would like me to ask?

As for the 4900 pack, they are enerland cells. I got this confirmed. Also, its strange that the performance is not being seen like the 5000mah long packs from what you have reported Tony that the heli guys are seeing. My contact during there testing didn't see that much of a difference between the pack performance at various discharge rates.

From my contact the Neu stuff is enerland cells.

Ultimately though, if I go with another pack, I may just look at the PQ6000mah again so i do get the runtime I need as it could be that alot of the issue is my driving style, and the extra 1000mah should work out there, though, weight will be greater.

As for the fan, is there a way to calculate how much mah would be pulled by the fan out of a pack for each minute of runtime? Sorry if this is an easy formula as that kind of numbers is not my thing.

glassdoctor

iTrader: (4)

Hmmmm

I suspect your heli packs may have additional factors that killed them, such as excessive heat and current.

I's true that deep discharging is not "good" for the life of the pack. I think it's good advice to not run a pack "dead" (3v/cell) as a habit... but stick to the basic 80% rule of thumb.

But, you are a little carried away saying that a single full discharge "definitely" damaged the pack. That's kinda like saying he ran once with scissors, so he surely fell and stabbed himself. well that sounded kinda funny to me anyway

If that was true then we would all have toasted packs... in fact almost every lipo sold in the rc market today would be ruined. Almost every ESC sold with lipo LVC would kill every pack, etc. Clearly it's not instant death to a lipo.

Consider: we have examples of packs that are just fine after even repeated "full dumps". For example, the SMC thread in the on road forum has results from a pack that has been cycled many times over several months of use. Each cycle is a full discharge to 3v per cell... essentially 100% capacity. Not only has this pack not died... but it's actually performing better now than when it was new. Runtime is down a little, but performance is actually better. Many of my packs have been dumped at least once without any apparent harm.

Also we have all the mfg data on cycle life of lipos at different depths of discharge, and they indicate reduced cycle life...not instant death. In fact I've seen info that shows almost the same total usable minutes during the life of the pack.

Ex: 80% discharge may show like a 20% reduction in cycles (500 @80% vs 400 @100%) but you also loose 20% of the runtime on every cycle. Total minutes of use is about the same. I don't have any real #'s but I've seen this basic concept in mfg data before on rcgroups.com

Occasional "100%" (3v/cell) cycles won't kill a pack.

glassdoctor

iTrader: (4)

Ex:150mah fan: 150ma per hour = 2.5ma per minute (150/60)

Consider a 200mah fan example:
200mah fan: 200ma per hour = 3.3ma per minute (200/60)

Your car:
4800mah/18minutes = 267ma per minute = 4.5ma per second

18 minutes x 3.3ma per minute = 59.4ma

59.4/4.5 = 13

In this example, a 200mah fan will use 13 seconds of runtime.

lxmuff

How did you get confirmed that the 4900 packs are enerland? http://enerland.com/product/p1.php?num1=1&img=y
is where we should see them. They have all of their cells listed with rates and dimensions on the site..

lxmuff

It is hard to say that's "bull" when you don't have the experience of these particular applications.

The LHS for our vehicles is big into heli's also. One of the best flyers in the state went back to nitro because he was draining hard and only getting about 50 runs out of a 6s 5000 enerland pack. We can get 20 minutes with a 4s 5000 enerland pack. With his 6s 5000 pack, he was averaging only a 5 minute run before he drained the pack.

The discharge rate on the heli is extremely higher than that of these 1/8th scale buggies.

badassrevo

iTrader: (12)

Hey guys,
I have a extra conversion kit for sale.
check it out,
http://rctech.net/forum/showthread.p...82#post4268982

Cowboy

iTrader: (5)

I have a Losi 8T with a Neu 1515 1.5D and a mamba max. This thing has WAY too much power with the punch control turned off. It is raceable with the punch control around 50%. It seems like a waste of motor to have to hold it back like that. Do you guys think a Nue 1512 2D with punch control off will be comprable to the 1515 at 50% punch? Would I get more run time? Will the 1512 overheat?