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Battery wire problem (for new Brand)

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Old 07-29-2011, 07:58 AM
  #1  
dr.pip
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Default Battery wire problem (for new Brand)

Just been looking at a new range of cheap and cheerful batteries which are getting good reviews overall.

But have noticed that on 1 re-sellers site they warn of the thin discharge wires being only 20AWG and caution people not to discharge above 11 amps...

So the batteries in question are rated at 25c discharge- burst 50c and charge rate up to 5c.
The particular range is up to 1300mah. (after that they change to 18awg for the 1500+ to 2200)

Not brilliant on this subject at all but if I have worked things out could this be dangerous?

I figure 1300 mah = 1.3 amps x 25c = 32.5 amps

I also looked up insulation properties and it appears that silicone is probably ok but
cheap PVC (which these use) is possibly only half the integrity at best and therefore (in this case) exceed the insulation rating by more then double.

No doubt this accounts for this one re-sellers caution but others sell with no mention at all and I realise that few will discharge at 25c.. but 11 amps is much easier to accidently over draw especially if you don’t even think about it as many wont.

I have since written to the manufacturer asking if they intend to deal with problem but they say that unless the customer requires "special order" they will just use their standard wire.

I am leaving out the "make " at the moment in case I am completely wrong

So question is "is this product actually unsafe" or am I really just splitting hairs?

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Old 07-29-2011, 10:04 AM
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Default RE: Battery wire problem (for new Brand)

The wires are kinda thin ... what you can do is to hook it all up ... run your power system at say 75% and see how fast the wires and connectors heat up and what level do they heat up to ...
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Old 07-30-2011, 04:22 PM
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Default RE: Battery wire problem (for new Brand)

HI yeah thats possible

However what I really want to do is "fry" one packs as a test. Such as : test cable insulation temp and amps until the leads burn out.

Temp is no problem I have a "no contact" laser meter for that

But doing the amps is not so easy without toasting the amp meter (I think). not sure if one of those 12v clamp over rings would do it but
I think they just do volts.. plus I dont have one just now.
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Old 07-31-2011, 06:51 AM
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Default RE: Battery wire problem (for new Brand)

For me a 20 guage is good for like 20A max ... it will heat up ...
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Old 08-02-2011, 04:01 AM
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Default RE: Battery wire problem (for new Brand)

I think you're splitting hairs. Yes, the wire is a bit on the thin side and silicon insulation would be nicer to have, but this probably helps to account for their lower cost. Either pay a bit more for a brand with wires that you do like, or change them.
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Old 08-15-2011, 02:05 PM
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Default RE: Battery wire problem (for new Brand)

AMP rating limits on wires is normally established using 220v or so, not the lower voltages we tend to use, so keep this in mind.



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Old 08-15-2011, 05:12 PM
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Default RE: Battery wire problem (for new Brand)

The battery size and wire is relevant to the type of model and motor that it is expected to power therefore controlling the level of amps likely to be used. In this case 10-12 amps is probably fine but the proposed 25c rating is both ridiculous and UNSAFE (50c burst completely impossible) due to this simple wire issue. For the experienced electric flyer, it shouldn’t cause a problem as they should pay attention and use accordingly. However this would easily be a problem for newbie’s.

Lots of comparatively priced batteries use the correct and safe cable size or have better insulation to cope. In this case the manufacturer has emphasised that they have used good quality covering (and yet wrong cables) bit of a priority problem there.

With help of others we looked at the amp ratings for 12v and cant find anything that doesn’t suggest that the insulation/wires on these are simply wrong.

Wires or course can be replaced but frankly unless you know want your doing its not something I would recommend.








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Old 08-15-2011, 07:47 PM
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Default RE: Battery wire problem (for new Brand)

If the application can really get to 25c, then the 20AWG discharge wires need to be replaced. Use 13AWG wires instead.
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Old 08-16-2011, 04:34 PM
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Default RE: Battery wire problem (for new Brand)

The wire is too small even for 10C discharge, performance will suffer due to voltage drop. Crymanolies, 20AWG is what I use for HD servo leads.
FWIW, I have a 20C rated 1300mAh Turnigy that has 14AWG discharge leads[8D]
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