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Tech Question - DC-DC Converter?

Curious question, in the Model S, the DC-DC Converter for the 12 volt battery. How much current could it handle for aftermarket accessories?

Can't answer that question, but the maximum current you can draw from the 12V socket is 15A since that's how it's fused. That's 180W max. You probably knew that already.

I don't think the DC-DC Converter runs continuously. I think it only activates when needed to recharge the 12V battery.

I guess you're trying to figure out how to power a 500W stereo or something. You could drain the 12V battery pretty quickly.

There are posts that the DC-to-DC converter is "undersized" but I couldn't find any source for that claim.

There's a YouTube video from user 'kmanauto' where he measures the current on the 12 V posts behind the nose. It shows a constant draw/charge even when the car is off. Can't remember the current, but was about 13.8V

Current is measured in Amperes.
Kmanauto was indeed measuring Voltage. I remember he thought it was high and would be bad for the 12V battery, although I didn't share that opinion. About 13.8V, yes.

If someone has the answer to this that would be great. On my Volt I can draw 190 amps off the 12 volt accessory power module. This is great if you every need to use the car as a stationary power source such as in a power outage along with and inverter. Yes is does void the warranty. Does anyone know where this module is located on the car?

I meant to say "Can't remember the current, but the voltage was about 13.8V"

In an ICE, the laternator normally keeps the 12V circuit at a bit under 14V, so it is no different in the Model S.

mrrjm wrote: "On my Volt I can draw 190 amps off the 12 volt accessory power module."

Uh, I think you meant 190 Watts, about the same as model S.

I am resurrecting this post since I could not find a definitive answer after many searches.

Does anyone know if the DC-to-DC converter is continually charging the 12V battery, even when the car is on Park? If there's a draw on the 12V battery during Park will the car allow it to drain or does the DC-to-DC Converter detect the low voltage and activate charging?