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Red Scholefield
11-07-2005, 07:22 PM
One of our club members had an unfortunate experience with a brand new
ElectriFly 1250 LiPo pack purchased through a local hobby shop. He charged
it through the charge connector and all was well. Then he put it in his
plane, a small 4 motored B-17 from a Gillow kit . . . smoke city! 4 motors
came on full force in reverse, 20 Amp speed controller toast.

The discharged connectors were wired in reverse at the pack terminals. Deans
Ultra that came on pack OK, red to --, black to | so he didn't suspect
anything.

Note the difference in the wires on a good pack (foreground) vs. the reversed wired pack.


Probably an isolated instance but check those new packs with your voltmeter
as soon as you get them.

gouch
11-08-2005, 03:54 PM
Why do they have the two pairs of wires in the first place?

What's the advantage of a setup like this?

Cheers
Paul

Red Scholefield
11-08-2005, 04:14 PM
The charge set of wires are for a charge protection circuit. Like you find in many consumer devices using Lithium technology.

GeraldRosebery
11-10-2005, 08:11 PM
One of our club members had an unfortunate experience with a brand new
ElectriFly 1250 LiPo pack purchased through a local hobby shop. He charged
it through the charge connector and all was well. Then he put it in his
plane, a small 4 motored B-17 from a Gillow kit . . . smoke city! 4 motors
came on full force in reverse, 20 Amp speed controller toast.

The discharged connectors were wired in reverse at the pack terminals. Deans
Ultra that came on pack OK, red to --, black to | so he didn't suspect
anything.

Note the difference in the wires on a good pack (foreground) vs. the reversed wired pack.


Probably an isolated instance but check those new packs with your voltmeter
as soon as you get them.

That's remarkable, what did the vendor (and the importer) have to say about replacing the damaged equipment and apologizing?

jfcgnv
11-10-2005, 09:10 PM
I am the person that Red is talking about. I called Tower Hobbies and they want me to send them the battery and the Speed controller. This was done 11/9/05. They said they would replace the battery and want to look at the speed controller. I expect them to replace it also. The B-17 sustained minor damage witch was repairable. The sad part is I am using a Graupner 4/2 three bladed prop on all four motors and they don't make that prop anymore. One of the props was broken when the B-17 went into full reverse and I was trying to catch the aircraft. Thank God there was no fire as the speed controller got extremely hot and was putting out a lot of smoke. I'll tell Red and post here the outcome from Tower Hobbies.

John C

gouch
11-10-2005, 11:48 PM
Can you see the irony of it? The very thing that was built in to protect, ended up causing a potentially serious problem.

donjiskra
12-02-2005, 10:09 PM
I would like to know what type of connector is used on the "Charge" wire set? I'd like to make a jumper cable so that I can use it with my Triton charger that is set-up with an Asto Zero Loss connector.

I asked at my LHS what to use but they did not have such a connector that would plug into the Li-Po battery "Charge" connector.
Also need to know the polarity of this connector.
Thanks for your suggestions.
Don

jfcgnv
12-02-2005, 10:32 PM
Hobbyco (Tower Hobbies) replaced my Battery and speed controller. The new Battery is wired correctly. I got the replacements today. All this was done at no cost to me.

I_Love_My_ABC
12-03-2005, 10:06 PM
Hobbyco (Tower Hobbies) replaced my Battery and speed controller. The new Battery is wired correctly. I got the replacements today. All this was done at no cost to me.

So they should too!! Their obligation to the customer should not stop at the point of sale. It's good to hear that good customer service is still alive and well in the RC comunity!!

BillB
12-04-2005, 03:04 AM
Seems that ElectriFly gets their wires crossed in another way as well. See this post in another forum where they apparently mixed up the charge and discharge leads. http://www.rcgroups.com/forums/showthread.php?t=306374

Bill

qban_flyer
12-04-2005, 04:21 PM
This incident plus the one I experienced with Electifly Li-Po packs leads me to believe the quality control at the factory must be very LAX!

In my case, the 'discharge' wires became intermittent after the third flight. Whenever I applied pressure to tie area where the charge/discharge 'module' is located, it would make contact and deliver power to its connector properly. As soon as I let go, the connection would open again. Can you imagine what would have happened to my plane if that failure had occurred in mid flight? :mad:

These incidents are unacceptable with any type of battery packs, but more so with Li-Pos. Their volatility demands strict quality control throughout the entire process. Failure to do so can and will cause a disastrous incident where someone could get hurt and property be lost to a fire. :(

Replacing these bad items is what they MUST do. They had better get a handle on this QC problem and fix it too. Failure to correct it will cause them to acquire the type of reputation in this industry most manufacturers hate. :o