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Discussion Starter #21
I don't think you understand what we are suggesting. That plug and attached foot and a half of cabling, unplugged from the inverter, is all that you need.
Suggesting I check continuity between the outer ring and the shielding?
121881


BTW I believe this is some hybrid connector Tesla has made or had custom made by amphenol. The left half is identical to an Amphenol HVPT connector however that wouldn't typically have the termination attached.
121882


Would love to work out what the tesla connector is so I can make one continuous cable from battery to inverter vs having a junction box
 

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Discussion Starter #22
So a quick test
121883


Red Is continuous with the shielding. This contacts the housing of the inverter which is strapped to ground.

The inner yellow is continuous with the conductor
 

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The left half is identical to an Amphenol HVPT connector however that wouldn't typically have the termination attached...
On closer look the connector more closely matches an AMP IPT...
That makes sense - the "PT" is just a pass-through (secures and seals a cable passing through a housing wall, with no connector at that location), while the IPT is the same housing with a termination, and the Tesla part is the same housing again with a different termination.
 

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Discussion Starter #26
That makes sense - the "PT" is just a pass-through (secures and seals a cable passing through a housing wall, with no connector at that location), while the IPT is the same housing with a termination, and the Tesla part is the same housing again with a different termination.
Sadly I can't identify what tesla has used for the actual termination as nothing in either catalogue even looks close. The AMP+ IPT is 100 percent the back body and what seals everything out as the measurements match. Just wish I knew the rest.
 

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I have tried a number of searches and can't seem to find a reliable answer to my question.

I am looking at using shielded 2/0 cable to connect my motor (Edit for clarification: Tesla Drive unit battery connection not the internal 3 phase) . My assumption is that the shielded would get grounded to the car and not the traction B- . Can anybody confirm this?

I guess second question. Am I overthinking things using shielded cable? Tesla SDU is the motor.
Shielded cable is a good idea. DO NOT ground it to the car though. The 12V is grounded to the car because it is a low enough voltage that it's safe. 300+ volts running through the frame is a terrible idea.

Why wouldn't you connect the wire to the B-? Am I missing something?
 

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Ohh... so close. We worked systematically why it would be bad to connect the shield to either side of the high voltage battery, established that the logical connection for the shield would be to the component housings, and confirmed that Tesla connects the shield to the component housing. Then we get this...
Shielded cable is a good idea. DO NOT ground it to the car though. The 12V is grounded to the car because it is a low enough voltage that it's safe. 300+ volts running through the frame is a terrible idea.

Why wouldn't you connect the wire to the B-? Am I missing something?
Don't connect the shield to the B- because 300 volt potential on exposed components is a bad idea. And if the normal B- path fails anywhere, the frame and component cases become the path for what could be hundreds of amps, instantly frying the little shield connections but creating huge voltages between components until it all fails. If you connect the shield to B-, you might as well use bare copper wire for B- everywhere, because your shield connection has bypassed the B- cable insulation.

Again, both sides of the high voltage system are isolated from any chassis or component ground or housing, and should be.
 

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Ohh... so close. We worked systematically why it would be bad to connect the shield to either side of the high voltage battery, established that the logical connection for the shield would be to the component housings, and confirmed that Tesla connects the shield to the component housing. Then we get this...

Don't connect the shield to the B- because 300 volt potential on exposed components is a bad idea. And if the normal B- path fails anywhere, the frame and component cases become the path for what could be hundreds of amps, instantly frying the little shield connections but creating huge voltages between components until it all fails. If you connect the shield to B-, you might as well use bare copper wire for B- everywhere, because your shield connection has bypassed the B- cable insulation.

Again, both sides of the high voltage system are isolated from any chassis or component ground or housing, and should be.
I read the post entirely wrong. I assumed he was just talking about the cable itself. I'm an idiot.
 

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Discussion Starter #30
That makes sense - the "PT" is just a pass-through (secures and seals a cable passing through a housing wall, with no connector at that location), while the IPT is the same housing with a termination, and the Tesla part is the same housing again with a different termination.
My continued search has bore fruit. I finally have the correct connector tesla uses.


Sadly looking at the assembly instructions (https://products.rosenberger.com/_ocassets/ma/MA_HV0104.pdf) the termination is ultrasonically welded so outside a home gamer capability. I was hoping it would be crimped. Though it further confirms how the shielding interacts with the connector housing.

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What I find curious is that Rosenberger specifies a max cable size of 50mm^2 but to the best of my abilities measuring the tesla cable it is 2/0 which is like 67.4mm^2. This wouldn't be the first thing I have found where Tesla disregards/modifies original manufacturer specs.
 

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My continued search has bore fruit. I finally have the correct connector tesla uses.

Good work. :)

Sadly looking at the assembly instructions (https://products.rosenberger.com/_ocassets/ma/MA_HV0104.pdf) the termination is ultrasonically welded so outside a home gamer capability. I was hoping it would be crimped. Though it further confirms how the shielding interacts with the connector housing.
I would have guessed crimped, too, but so there is so much ultrasonic welding in the battery modules that perhaps it is accepted as a routine production method now.

What I find curious is that Rosenberger specifies a max cable size of 50mm^2 but to the best of my abilities measuring the tesla cable it is 2/0 which is like 67.4mm^2. This wouldn't be the first thing I have found where Tesla disregards/modifies original manufacturer specs.
They're also using it at way beyond the rated 240 amps, so that makes some sense...
 

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Discussion Starter #33
Good work. :)


I would have guessed crimped, too, but so there is so much ultrasonic welding in the battery modules that perhaps it is accepted as a routine production method now.


They're also using it at way beyond the rated 240 amps, so that makes some sense...
My guess is tesla has just done their own math and used driving habits to work out how long over the rated capactiy a given connection might live and that they are happy with the transients. Since outside a few seconds of heavy accel the motor would hardly be drawing max levels.
 
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