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Is the battery post under the nose cone fused?

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Here is a picture of the DC to DC inverter in the passenger side front wheel well. I had it open last night to install 12volt to the cabin. I was looking at connecting directly to the DC to DC inverter for a 400 watt DC to AC inverter but was concerned about the effect it might have on the DC to DC inverter. The red connector is the 12Volt to the Low Power Battery and the black cable is the ground to the negative terminal.
Model S Passenger side wheel well.png


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I chose an AIMS Power Pure Sine-Wave 300 Watt (Peak 600w) with a pure sine wave. It has one USB port and I added a fuse link. I almost installed it last night, but decided to finish my Blackvue 650 2CH system first.
 
Here is a picture of the DC to DC inverter in the passenger side front wheel well. I had it open last night to install 12volt to the cabin. I was looking at connecting directly to the DC to DC inverter for a 400 watt DC to AC inverter but was concerned about the effect it might have on the DC to DC inverter. The red connector is the 12Volt to the Low Power Battery and the black cable is the ground to the negative terminal.
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I chose an AIMS Power Pure Sine-Wave 300 Watt (Peak 600w) with a pure sine wave. It has one USB port and I added a fuse link. I almost installed it last night, but decided to finish my Blackvue 650 2CH system first.

The DC-DC is no longer there in newer cars. It was moved to the center area behind the frunk and in front of the firewall area.
 
The cable from just behind the nose cone (red terminal) going back to the 12v battery is rather thin gauge so will itself limit the max current that can flow. That 50A fuse (fusible link) on top of the 12v battery will be difficult to blow using the full length of this wire all the way to the nose cone. When Rangers jumper in a fresh 12v battery to these posts therefore no huge inrush of current, even though the car's battery is now dead. But just enough to reactivate the DC-DC charger to once again do its job maintaining the 12v battery.
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My earlier car has the DC-DC converter in the wheel well like that. Those connectors don't look particularly salt-water resistant and I wonder how much water spray gets in there behind the wheel well liner. Northern roads are rivers of salt brine most of the winter where I live.
 
The fuse can be removed and replaced. It seems to be held on by some nuts.

Sounds good. I found a higher resolution image of the battery and it looks like all those yellow, orange, and blue squares are fuses (perhaps AMI or MIDI style) that are held on by nuts at each end. Yellows look like they have 60 printed on them, the blue is 200, so if there's a 50 amp fuse I assume it's the orange. Marking on the orange is unclear in the picture. If the color coding matches other AMI fuses I found online, then orange should be 30A. It's possible the nose uses a 60A fuse and the tech said it was fused for 50A because you can draw 50A continuously from a 60A fuse (not sure if that's true, it depends on the fuse).
 
Sounds good. I found a higher resolution image of the battery and it looks like all those yellow, orange, and blue squares are fuses (perhaps AMI or MIDI style) that are held on by nuts at each end. Yellows look like they have 60 printed on them, the blue is 200, so if there's a 50 amp fuse I assume it's the orange. Marking on the orange is unclear in the picture. If the color coding matches other AMI fuses I found online, then orange should be 30A. It's possible the nose uses a 60A fuse and the tech said it was fused for 50A because you can draw 50A continuously from a 60A fuse (not sure if that's true, it depends on the fuse).
Here is the Battery-Mounted Fusebox Layout ... the 12V posts are confirmed to use a 50A fuse :cool:
upload_2018-1-21_11-28-40.png
 
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What a great thread -- sorry I didn't find it before blowing this jump post fuse!

I was experimenting with an induction cooktop running off an inverter connected to this front Jump Post. I got up to 800 watts (75 amps!) without trouble, but tried for 1000W and something in the Tesla blew -- the post is now dead. I have a 2015 90D, and can't find the 50 AMP F83 "Jump Post" fuse mentioned above by FlatSix911. I also don't see it anywhere on this list of 2015 model S fuses.

Happily, the car runs fine. But any suggestions on where to find this fuse so I can start cooking again would be appreciated.
 
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What a great thread -- sorry I didn't find it before blowing this jump post fuse!

I was experimenting with an induction cooktop running off an inverter connected to this front Jump Post. I got up to 800 watts (75 amps!) without trouble, but tried for 1000W and something in the Tesla blew -- the post is now dead. I have a 2015 90D, and can't find the 50 AMP F83 "Jump Post" fuse mentioned above by FlatSix911. I also don't see it anywhere on this list of 2015 model S fuses.

Happily, the car runs fine. But any suggestions on where to find this fuse so I can start cooking again would be appreciated.
I assume that you have a 2015 Model S, correct? The fuse box shown in the diagram is mounted to the top of the battery in early 2014-2015 models.
IIRC, the box was moved later in the 2015+ production to improve access to the 12V battery. Check the front firewall and under the passenger dash.
Hope this helps.
 
If it’s any use here is one file. I have also situation that behind the nose cone is only negative (black) terminal and I can’t find any location where to attach that missing positive terminal (on the fusebox side). So far I favour F3 as it’s “not in use” according to this document and it’s free spot to accommodate required 50A fuse.
 

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I assume that you have a 2015 Model S, correct? The fuse box shown in the diagram is mounted to the top of the battery in early 2014-2015 models.
IIRC, the box was moved later in the 2015+ production to improve access to the 12V battery. Check the front firewall and under the passenger dash.
Hope this helps.
FlatSix911: yes, it's a 2015 Model S. But it must be the later version you mention: I have no fuse box on top of the 12V battery, and the two boxes behind the battery (closer to the cabin) do not have anything that could match and none are blown.

Maybe it's in a fuse box labelled "No 1" in this diagram, but I can't figure out how to get to it:
Tesla-Model-S-2013-2016_en_loc_fuse-box-location.jpeg

Any suggestions appreciated.

KalJoMoS thanks for the PDF. Seems the Cabin Fusebox doesn't have any fuses big enough for the "Jump post".
 
FlatSix911: yes, it's a 2015 Model S. But it must be the later version you mention: I have no fuse box on top of the 12V battery, and the two boxes behind the battery (closer to the cabin) do not have anything that could match and none are blown.

Maybe it's in a fuse box labelled "No 1" in this diagram, but I can't figure out how to get to it:
View attachment 737105
Any suggestions appreciated.

KalJoMoS thanks for the PDF. Seems the Cabin Fusebox doesn't have any fuses big enough for the "Jump post".
Good diagram - thanks for sharing. Check the fuse box in the No. 1 location and I think you will find the 50A fuse.
 
I'm writing my experience trying to hookup a Duracell 3000 Watt High Power Inverter to my 12v connector on Model S P85+ as an emergency power source and blowing 50amp fuse and adventure in repairing it.

I hooked up 3000w inverter and 12v behind the nose cone. It did power up. I tried to power up 1500w Vornado space heater and apparently heater detects insufficient power and didn't heat up. Then I tried Dewalt 10 gallon wet/dry vacuum and in it ran for a few seconds and blew the 50 amp fuse.

In the process of repairing blown 50 amp fuse, I found that I could plug inverter directly to positive terminal. However, I do see a 225 amp fuse attached to it. I will give up my experiment in trying to hookup a high power inverter to 12v. Instead, I'll look for an Ecoflow Delta or Delta max and some solar panels as an emergency power source. In time of emergency, I probably will need two 1000w-1500w watt as power source. Although inverter can handle such load, I'm afraid that I might fry many fuses in the process. If you really want to use 12v as power source, you will really need to various tests to make sure it can support such load with extended period of time without causing problem.

Here is what I did to repair 50 amp midi fuse.
I bought O'Reilly Auto Littlefuse 50 amp fuse Part # MID50 from O'Reilly Auto and it's an exact fit.

Thanks to FlatSix911, the location of blown fuse is exactly at F83 on the fuse box on top of 12v battery. However, this is on the second level. I had to disengage all wires on the first level to get to the second level. F83 is the one where I point voltage meter lead to it.
 

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