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Old 09-03-2004, 08:16 PM   #1
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Default Ce Gfx

Hello All,

I am wondering if anyone has tried this and what the thoughs
are behind this. Soldering the sensing leads to the main
leads at the aligator clips. Basically eliminating the need for 2
sets of aligator clips. I am aware that the sensing leads are
for discharge accuracy but is that all they are for?

Thanks for any comments.
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Old 09-03-2004, 08:24 PM   #2
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I did it and the discharge function works fine
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Old 09-03-2004, 08:59 PM   #3
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In the rcca review, I think they said they contacted CE and they said that its a bad idea to put them on one clip.
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Old 09-03-2004, 09:22 PM   #4
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Having the sense lead and main lead going through the same clip is a bad idea, the croc clip connection when under load can be way off which will give errors on the numbers when charging and discharging.
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Old 09-03-2004, 09:51 PM   #5
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Do you think they would spend the extra coin on the leads if it did not matter? CE is not a half a$$ company... if they did it, there is a reason for it.
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Old 09-04-2004, 08:05 AM   #6
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it would throw off the readings. try it attach the small leads on to the main leads and look at the reading. then attach it directly to your pack it will give a diffrent reading.
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Old 09-04-2004, 10:18 AM   #7
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I'm with SMALLS and STRIKER but, and that's a big but, aren't the clips, big or small, attached to the same battery tap, that's also under load? So what's the difference? Being the clip or the tab?
Can anyone put some light on this?
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Old 09-04-2004, 10:31 AM   #8
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Default CE GFX Small clips

You are suppose to put the small clips on the battery not on the big aligator clips. So the voltage sensed by the small leads is the actual voltage.
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Old 09-04-2004, 11:14 AM   #9
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How can we read different voltage values on the very same piece of metal, the bat tab?
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Old 09-04-2004, 11:20 AM   #10
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The big aligator clips have a certain voltage loss and at 35-35 amp discharge the clips get hot and resistance goes up. If you solder the small clip to the big one the small clip then will have the voltage loss of the battery bar and the big aligator clip. this is why the instructions said to clip the small aligator clips on to the battery directly and not on the big aligator clips.
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Old 09-04-2004, 11:43 AM   #11
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The small leads are just sense wires, they carry no load and detect the actual voltage at the cells. When you put a load down the wire there is a voltage drop associated with it. If you put load down the sense wires the internal volt meter will not see th volt drop and it will show you a lesser voltage than it really is. Now the higher the load the higher the volt drop, so i'd imagine at 35 Amps you will probably get around 0.2V drop down the leads, that is a lot in our cells, if the charger didn;t get around that you would think you had a terrible set of cells when they may be pretty good. The problem with alligator clips is that sometimes you get a better connection than others which will make the voltage drop vary greatly. This is got around quite easily if you don't have any load going through the clips, hence the existance of the seppearte sense wires
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Old 09-04-2004, 12:18 PM   #12
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Crimson I have to agree with you but....

Here are my reasons for wanting to do this....

1) If you are discharging for the fact of finding out
approximatly what you have left in your pack then really
all you are getting is an approx anyway correct? The reason
I say that you are getting an approx anyway is are the cells
truely equal @ 5.4v on discharge? According to my tray they aren't.


2) I have 2 victors and both have the leads (meter / battery)
soldered to the same clip and I have never found it to be a
problem.

Please feel free to correct me as I want as much good / bad
reasons to help me decide if I should do or don't.
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Old 09-04-2004, 02:26 PM   #13
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Default From CE website

Voltage sensing and current draw leads

The voltage sensing leads (small wires) are not dependant on length. You can make tem any length you want. They need to be connected to something that is soldered directly to the battery. That is why we make them separate from the current wires (large wires). There is a voltage drop at the point where the current jumps from the battery terminal to the current clip. If you solder them to the current clips, or attach them to the current clips, the voltage is being measured after the drop occurs. A typical error would be about .30 volts with a 30 amp discharge rate. That means your 6 cell pack will cut off at 5.70 volts instead of 5.40. The current carrying wires can be lengthened, but if you want to discharge single cells at 35 amps, the wires will need to be kept original length. The calibration of the unit is not dependant on wire length, but its ability to control current at the extremes may be compromised when a lot of wire is added.
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