Puff goes the lipo pack....

[Steven Vaccaro]

So what happens when you run a 4s boat(no lvc) and (2) 2s lipo packs but one of them is almost dead? It puffs like a balloon! Like a twit, I picked up the wrong pack and instead of having 2 fully charged packs, I ended up with a 100% pack and a pack that was about 30%. After running for about a minute the boat slowed. I run where there are some weeds, so I did a lap to see if I could get what I thought were the weeds off. That one lap did my pack in. I felt like a idiot when I opened the boat to see what was going on! It was an expensive mistake.

It seems user error is the problem with most lipo problems. I receive many emails from customers that have lipo issues. Most times, people seem to not realize what kind of current these brushless motors will pull. I think the best rule of thumb would be to buy the best you can afford.

[Steven Vaccaro]

I forgot to add my question! Is there a LCV product out there that simply plugs between the pack and esc and monitors the total voltage of the packs? Another words, something that doesn't need to be wired/soldered into the system.

[Dr. Jet]

I always put a piece of blue masking tape tape over the connectors on my batteries as soon as they come off the charger. When I am at the pond, I never connect a battery that doesn't have a piece of tape on the connector. I check the non-taped batteries with a multi-meter and make a go-no go decision based on the indicated pack voltage.

Putting the tape on the connector forces you to go through an additional step to install a battery. Inadvertanlty installing a partially-discharged pack is nearly impossible.

[Darin Jordan]

Similiar to Dr. Jet, I use the "Post-It" tabs that we have here around the office... When the batteries come off the charger, I stick one of the tabs on them... If there isn't a tab, I assume it's not charged.

Not sure about the LVC question. Would be nice to have some kind of monitor.

Cell management is definately important to keeping errors from happening... You aren't the first experienced person to have this happen, Steven, believe me!

[C.Smock]

I am unsure about the LVC also . But we put caps over one of the wires of the packs. When charged, we put it on the positive lead. When discharged or uncertian we put it on the negative lead. As long as we (my dad and i) follow protocol (SP) the wont be a mishap. We have gotten everyone in our club started doing this and knock on wood no accidents.

[ED66677]

Steven, there actually one I found that does the BEC function, but I think it requires soldering, I can't see how it could sense the pack voltage if it was not directly connected to it, the good thing about it is that it connects between the receiver and the ESC, it is fully programmable, when the voltage drops to a pre-define value (per cell) the thing reduces the signal (from receiver to ESC) so the motor goes slower
there's one http://www.dimensionengineering.com/SmartBEC.htm

Also LipoShield does the same protection by modifying the throttle signal but has no BEC http://www.littlebirdz.com/proddetai...a3e03fc087233b

this one http://www.atsrcplanes.com/lisaver1.htm exists with BEC

[JimClark]

Novak makes a 2s, 3s and a 4s one. It would be a piece of cake to waterproof it

http://www.teamnovak.com/products/lipo_cutoff_module/index.html

Jim

[Heath M]

There's this one also

http://www.schulze-elektronik-gmbh.de/LiPoDiM-e.htm

Heath

[SteveReesor]

I used to use all kinds of systems to determine if my packs were fully charged. When you get busy at a race, or thrashin', whatever you want to call it, you WILL forget the system.

I now use a LiPo Cell Meter

http://www.hobby-lobby.com/cellmeter.htm

Best investment for cell management I ever bought, and I own a LiPoDimatic.

I always use the Cell Meter to check the pack before I tape up.

[SweetAccord]

I forgot to add my question! Is there a LCV product out there that simply plugs between the pack and esc and monitors the total voltage of the packs? Another words, something that doesn't need to be wired/soldered into the system.

You mean like this?

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6233&Product_Name=TURNIGY_8-15A_UBEC_for_Lipoly

This is easy and cheap too to use:

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idproduct=6260

[Apples1]

check these out, a guy at the club has just started using this and it works a treat!

https://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=7068

not sure how well it will work with two or more people using the same product?

[Doozie870]

I have had good luck running 2X 2s off of one tap. You will still have the flexability of two 2s packs for weight placement.

[ED66677]

I like the idea of the Schulze that connect to the balancer tap via an adapter... no extra wiring!

[Mich. Maniac]

Very unlucky Steven. That is a good point when we run packs in series like that. I have noticed most esc's have built in LVC that can be programmed to 12V.