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Discussion Starter #222
I appreciate all of the comments about the steering rack. I will likely try to take my rack out. At that point I may come back looking for some advice.
 

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Discussion Starter #223
Alright my electrical friends, I need your advice.

I believe that I might have a high voltage electrical leakage problem. I do not believe that the cooling elements on the LG Chem battery modules are truly isolated from the power. I have made a little video to show what I am finding.

https://youtu.be/BEOsgVNz0xY

I am very inexperienced and this may be normal. Please share your thoughts and advice. Also let me know if you think this is relevant enough to put into another forum section for further advice.
 

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I have no experience with large batteries.

The voltage staring high and then dropping... with how infinitesimally low current draw your multimeter takes to measure the voltage, says to me there is alllllmost zero leakage. And/or it's capacitance.

You get capacitance any time you have a conductor separated by an insulator.

For example, a slab of PVC with aluminum foil on either side. Zero electrical connection (PVC is an insulator), but, it's a capacitor. If you connect a voltmeter to either side, you'll briefly get a voltage that then drains. That voltage can, to a microscopic degree, self-charge as well.

Or, two wires. Like the positive and negative cables.

I'm not enough of an expert other than to hint at capacitance as a cause, maybe someone who understands it better can offer better context.

As to the cooling, I'm not familiar with the internal cooling loop and whether it should be isolated or not. It would be a lot of extra work to be electrically isolated, but the alternative is that the battery cases will carry a huge voltage.

Radiators I imagine cannot be ever isolated, there's not some insulator covering their entire innards and the coolant itself is conductive, so, if there's voltage to the frame there's voltage on the rad. So it seems like that should never be allowed to be the case, and thus there should be voltage on the cooling lines.

Not much help but, just a couple things to bounce off of.
 

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Discussion Starter #225
I think you are right. I didn't think about the capacitance affect. I guess I should be trying to measure current rather than voltage to see if I have a leak. Thanks for your insights.
 

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One way to tell is if the voltage drops as you keep measuring. If you put a small incandescent lamp or other load in series (parallel?) with your meter it might give more information. If a small lamp stays lit you have an issue, very similar to measuring current.
 

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I think you are right. I didn't think about the capacitance affect. I guess I should be trying to measure current rather than voltage to see if I have a leak.
I suspect it will be almost immeasurably low.

If your multimeter was enough of a load to draw the voltage down in moments, such that whatever the voltage leak is can't keep up, then the leak must either be minuscule or it's capacitance.
 

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Good to hear there was no real current leakage.

Just FYI... the voltage can be there all the time, current is how much charge is flowing.

What you're seeing is that nothing is actually leaking. Nothing is flowing. A charge is building up, but that's all.

In the same respect, rubbing your feet on the carpet can generate 10,000v, enough to zap a doorknob. And that voltage can exist for hours at a time. But zero current is flowing. And if you do get it to flow, zap, and now they're equal and nothing else flows.

You can think of it like a couple drops of water on a leaf of a fairly tall tree. Voltage is the fact that those droplets are not at ground level. It's their potential energy (in fact, voltage is often called "electrical potential").Current is how many drops are flowing per second. You have the equivalent of dew condensing on a leaf, slowly. What you want to make sure is that there's not a trickle, even a small one. Which you've now confirmed. Yes, there is a couple drops on the leaf, but even the way you measure it is enough to wick that moisture away back to nothing. There's no flow, and the rate at which dew condenses is so gradual that it's microscopic, and, it has a ceiling. Next to this tree, is a small dam the same height. The dam (enclosure, insulation) is holding back a lake (battery). Your concern is "Wait, why am I seeing water, off the ground, outside the dam?", the worry of which is, is the dam leaking? Will the lake slowly drain out of this leak? Is this leak going to hurt anyone? And you've discovered, no, there is no leak, the water on the leaf on the tree probably isn't even related except perhaps that around the lake the air tends to be moist. You flick the leaf, the drops fall, and there's no more water to fall.
 

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Discussion Starter #230
Good to hear there was no real current leakage.

Just FYI... the voltage can be there all the time, current is how much charge is flowing.

What you're seeing is that nothing is actually leaking. Nothing is flowing. A charge is building up, but that's all.

In the same respect, rubbing your feet on the carpet can generate 10,000v, enough to zap a doorknob. And that voltage can exist for hours at a time. But zero current is flowing. And if you do get it to flow, zap, and now they're equal and nothing else flows.

You can think of it like a couple drops of water on a leaf of a fairly tall tree. Voltage is the fact that those droplets are not at ground level. It's their potential energy (in fact, voltage is often called "electrical potential").Current is how many drops are flowing per second. You have the equivalent of dew condensing on a leaf, slowly. What you want to make sure is that there's not a trickle, even a small one. Which you've now confirmed. Yes, there is a couple drops on the leaf, but even the way you measure it is enough to wick that moisture away back to nothing. There's no flow, and the rate at which dew condenses is so gradual that it's microscopic, and, it has a ceiling. Next to this tree, is a small dam the same height. The dam (enclosure, insulation) is holding back a lake (battery). Your concern is "Wait, why am I seeing water, off the ground, outside the dam?", the worry of which is, is the dam leaking? Will the lake slowly drain out of this leak? Is this leak going to hurt anyone? And you've discovered, no, there is no leak, the water on the leaf on the tree probably isn't even related except perhaps that around the lake the air tends to be moist. You flick the leaf, the drops fall, and there's no more water to fall.
Great analogy. Thanks
 

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Bummer, but seems like it’s headed towards right direction. Im not expert but it’s pretty surprising the tin vs gold pins could also be an issue. Hope you get it driving soon.

I also bought the Tesla Model S Drive unit kit from EV west a month back . There is a 18 week lead time to prepare/ship. I hope I get gold pins when my kit is ready.
 

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Discussion Starter #233
Bummer, but seems like it’s headed towards right direction. Im not expert but it’s pretty surprising the tin vs gold pins could also be an issue. Hope you get it driving soon.

I also bought the Tesla Model S Drive unit kit from EV west a month back . There is a 18 week lead time to prepare/ship. I hope I get gold pins when my kit is ready.
Good luck friend! I hope you have better luck than me.
 
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