SV27 RUNTIME SHORT!....BATTERIES?
 

Ok so I have my sv27 and I ran the boat today,and it ran for about 5-8 mins,when I ran it for the 1st time it didn't run much longer than that...about 10-12 mins? is this normal,I have the PROPHET PLUS CHARGER.Amps Meter=4.73-5.00 AMPS?, VOLTMETER SAYS*ANYWHERE FROM 8.00-9.4 VOLTS? I dont know what the deal is.so I called someone up and they said to charge them at a 1 amp rateto see if they will improve the runtime will it?(when the batteries said they were done,tonight...it said it only charged 1274 MAH? when I charged them today to a full charge*HEARD THE BEEP!*:D so what could possibly be the problem!?? Thanks!

-Dwight

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

The most important info (missing) is the battery capacity. If they are over 3000 then runtime of 10-12 minutes seems normal and it seems that 1 battery shut off too soon or maybe even both of them. Charger says full, but they are not. To verify whether they are full check battery temp, should be around 110-120 deg F.

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

Have you changed the trim on the boat since you ran it last to correct bouncing or other problems? If the boat runs wetter (bow down) it will use up the batteries much quicker. Are the motor and batteries hot after running? If so you have something draging or binding. If you batteries and motor are cool and your runtime short then your batteries aren't charged fully or taking a full charge. A bad cell could cause this.

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

No I haven't Changed the trim tabs,when my 1st battery after I got home charged over 3000 mah,and the 2nd was still in the hundreds....should I charge them more?(guver) I charged them 1 time,and they got REALLY hot,so is this normal? because all this doesn't add up right,I was told to charge the batteries at 1 amp...and see if the battery life improves[&o] I hope I can figure this out..Thank you both for your help,I will keep ya posted:)

-Dwight

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

sounds like the one battery is bad and lost it's capacity. i charge mine at 3.5-4.5 amps usually and they're fine. it makes for a good mix of run time and punch. one amp must be ubber slow. and don't leave yor batts unattended whilst charging:eek: i've had one blow in a boat. so in a house or garage your looking for a fire

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

When they are hot, they are full. They should always require the same amount of charge since they are used in series. Skiddo could be right, maybe 1 is bad already. Or you got them off balance by chargeing 1 full and then using it with the other one that didn't get full.

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

well why would they say they are charged when at only 2000 mah charged? on 1 and the other in the hundreds? and how can I fix that,it *BEEPS*....kinda upsetting lol....anything I can do?;)

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

Charge them right before you run. NiMH's don't like to be stored, they loose charge and need cycling to bring them back up. I store mine charged, run them and then recharge them again and run them a second time, the second run is always better than the first after storage.

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

Ok but why is the batteries telling me they are fully charged at 900 Mah,and charging them at 1 amp?,(was told this to bring the battery life back up,true or false?) do I just keep pressing the start button till it gets up to 4200 Mah or wouldn't that ruin the batteries?:( Thanks!

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

Do you have an IR temp gun? What Batts are they.

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

I have a friend that has a temp gun,they are 2 cell 4200 Duratrax cells (=....I will ask if he I can borrow it,what else could be a possible problem do you think?:) Thank you very much!

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

If your charger is older it might peak too quick. Some chargers sense internal resistance and not voltage or temp. A bad cell will have more resistance than the rest causing a false peak.

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

I've heard that these may be one in the same with teh IB4200's of which I have two sets. My experience is that these loose a charge fast. Some times if they sit for a week or so on cell will drop to zero while others will be above a volt. Can you measure the voltage of each cell? (are they side by side). Anyway when this happens one amp doesn't seem to wake that cell up. I usually hit them with 3 amps for a few minutes, you'll see the voltage come up. Then I drop back to .5 if I'm doing a forming charge to balance them out again. If I do the 0.5 right off the bat that cell will not come up to voltage. Ive seen this on 3 of the four 4200 packs that I have.

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

I get about a 7 minute timed and logged run (micro logger) with IB 4200's using a 41mm prop. IB4200's are very bad for self discharging. After about 2 days at rest I lose 1000mah from them. Always re peak them before going out for your first run. Batteries run well when warm and freshly peaked.

Off the charger a six cell pack should be nearly 9 volts.

I currently have a "dead cell." It will charge to 5000mah without any heat, they only feel warm to the touch after I stop them at 5000. The cell will only discharge 4000mah from it at 3A to 0.9v. The problem is after 2 days voltage drops to -0.05v, yes negative while the other 5 cells still show 1.30 -1.35v per cell. I'll probably end up buying another sport pack of IB4200's just to steal one cell, as I can't find single loose cells anywhere.

I own 7 six cell packs and perform more maintenance on these then on all of my nitro boats.

Ryan

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

ryan,
I think I'm in the same boat with dead cells and agree with the mamount of maint. I'm thinking of converting to 7 cell IB 3600 packs. I've heard the 3600's aren't as high maint.

dayton

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

I don't have any problem with the maintenance part. What I don't like is losing cells. So far I haven't had a problem with the DTX packs.

I have also heard that the 3600 older cells tend to have much less of a self-discharge rate compared to the new 4200's. They also have a better quality rep.

Ryan

RE: SV27 RUNTIME SHORT!....BATTERIES?
 

Ok...so what should be do about the issues with my batteries?[:o]