dc to dc converter and warranty

[msanghavi]

hi all, will the dc to dc converter be warranted under the "main" warranty (new vehicle limited warranty) which is 4 years/50k miles, or the battery/drive unit warranty which on the SR is 8 years /100k miles?

I would like to add an aftermarket sound system that directly taps into the dc to dc converter, but only after my warranty expires, so wondering which warranty will apply. Thank you in advance.

 

[camalaio]

"Main" warranty by recent accounts that required replacement (at cost of owner).

 

[gaswalla]

It is definitely not included in the battery/DU warranty. If you know the cost of replacement, you wouldn't be messing with it!

 

[user212_nr]

Why do you think that your work impacts the "dc-dc converter" specifically? The dc-dc converter is hooked up to the 12v battery. If you hook up to the output of the dc-dc converter, would not the power primarily come from the 12v battery?

Its not clear what you are saying here, but just connect your sound system to the 12v power which is available in the car, and make sure to learn about how it works.

The battery has more power available than the DC-DC converter would.

 

[smatthew]

Why do you think that your work impacts the "dc-dc converter" specifically? The dc-dc converter is hooked up to the 12v battery. If you hook up to the output of the dc-dc converter, would not the power primarily come from the 12v battery?

Its not clear what you are saying here, but just connect your sound system to the 12v power which is available in the car, and make sure to learn about how it works.

The battery has more power available than the DC-DC converter would.

what are you talking about? The DC-DC converter can supply 2.5kW of 12V power. The battery has a capacity 1/5 of that. In the end, no energy comes from the 12V battery when the car is awake. It all comes from the DC-DC converter. The 12V battery just acts as a storage buffer.

 

[Rocky_H]

The battery has more power available than the DC-DC converter would.

Heh--that is the opposite of true, and @smatthew is correct.
I'm surprised no one has linked in this sticky posted thread about this yet. It's 10 pages so far of pretty detailed discussion on the 12V system's capabilities in the Model 3 and Y.
MASTER THREAD: Powering house or other things with Model 3 12V battery

 

[earthwormjim]

what are you talking about? The DC-DC converter can supply 2.5kW of 12V power. The battery has a capacity 1/5 of that. In the end, no energy comes from the 12V battery when the car is awake. It all comes from the DC-DC converter. The 12V battery just acts as a storage buffer.

The 12V battery can supply far more than 2.4kW, especially for transients, up to 650 amps.

See page 18:
http://dl.hankook-atlasbx.com/updata/2018/09/20/1537497249313_1_45049.pdf

Heh--that is the opposite of true, and @smatthew is correct.
I'm surprised no one has linked in this sticky posted thread about this yet. It's 10 pages so far of pretty detailed discussion on the 12V system's capabilities in the Model 3 and Y.
MASTER THREAD: Powering house or other things with Model 3 12V battery

That doesn't make any sense, the battery can supply up to 650 amps for short durations. The DC-DC converter cannot supply that much current ever. The battery can provide far more power than the DC-DC converter. If we're talking steady state, then okay, the battery will discharge very quickly at 2.4kw of continuous draw.

 

[smatthew]

The 12V battery can supply far more than 2.4kW, especially for transients, up to 650 amps.

See page 18:
http://dl.hankook-atlasbx.com/updata/2018/09/20/1537497249313_1_45049.pdf



That doesn't make any sense, the battery can supply up to 650 amps for short durations. The DC-DC converter cannot supply that much current ever. The battery can provide far more power than the DC-DC converter. If we're talking steady state, then okay, the battery will discharge very quickly at 2.4kw of continuous draw.

You're talking about Cold Cranking Amps. Which are irrelevant for EVs. Let's look at the definition of Cold Cranking Amps to see why.
"CCA is a rating used in the battery industry to define a battery's ability to start an engine in cold temperatures. The rating refers to the number of amps a 12-volt battery can deliver at 0°F for 30 seconds while maintaining a voltage of at least 7.2 volts."

And that number is irrelevant for EVs. At 7.2 volts the car can't even run the computer and would un-gracefully power-off.

This is why Tesla says "DO NOT JUMP OTHER VEHICLES WITH A TESLA"

I can guarantee that the 12V battery will not sustain 12V with a 200 Amp load. The DC-DC converter can.

 

[lascavarian]

I can guarantee that the 12V battery will not sustain 12V with a 200 Amp load. The DC-DC converter can.

Following some of this discussion, I can see that the inverter seems to be in the 2.5 kw capacity. I have done essentially what is described here. Running an EV and pulling DC off the 12v battery for power while the traction battery resupplies the 12v battery through the DC-DC converter. At some point I begin to wonder if the wiring for the DC-DC converter is up to sustained loads of 200 amps at 12 v. Might be, just not certain.

Interesting discussion.

 

[camalaio]

Following some of this discussion, I can see that the inverter seems to be in the 2.5 kw capacity. I have done essentially what is described here. Running an EV and pulling DC off the 12v battery for power while the traction battery resupplies the 12v battery through the DC-DC converter. At some point I begin to wonder if the wiring for the DC-DC converter is up to sustained loads of 200 amps at 12 v. Might be, just not certain.

Interesting discussion.

The nice bit is that the PCS (DC-DC converter) is liquid cooled. Some parts of it may be less cooled than others (e.g. the transformers).

It's a fair point though. I'm not really sure why the PCS is designed to source so much power. There are a lot of loads that can peak briefly (windows, parking brake, "normal" brakes via iBooster), but then it still seems to have quite a surplus (plus, one would think the 12V battery could also source the power for these brief loads). There's a very large difference between being designed to handle a 200A transient and a 200A continuous load, and I don't think we know for certain that it's designed for operating near the limit for so long. I certainly can't imagine a case with the car where that could be done normally.

• Drive standby (lights, pumps, etc.): ~500W
• All heated seats happen to be on at once: 500W ?
• Blower fan on max: ~200W ?

Actually, never mind. I see it. If the coolant pumps also decided to go nuts (Track Mode, for example), it can actually feasibly start to draw close to 2kW if a bunch of other stuff is on. The remaining overhead is probably needed for the brief loads mentioned above too (again, track mode especially, that iBooster would be working hard).

The thing I'm now curious of is if it gets sufficient cooling. Track Mode, for example, ramps up the pumps and such. But it's probably fine.

 

[joe415445]

Why do you think that your work impacts the "dc-dc converter" specifically? The dc-dc converter is hooked up to the 12v battery. If

you hook up to the output of the dc-dc converter, would not the power primarily come from the 12v battery?

Its not clear what you are saying here, but just connect your sound system to the 12v power which is available in the car, and make sure to learn about how it works.

The battery has more power available than the DC-DC converter would.

Would a blown fuse in there that went to ptc heater cause this problem. I'm aware ptc heaters have a lot of problems and I swapped the 3rd gen one out for a new one. That fired right up and worked for a day or two. After going to super charge and returning home I proceeded with software update and then all the problems arose. Is it possible tesla needs to do some kind of reset? Images attached