12V Electrical System Amp Output?

It’s 80…100A (depending on who you ask) minus whatever Prius itself is using. But voltage might drop before you get that out of it. Of course 12V battery will provide the extra for peak power. You should but good 12V battery in it.

 

1000 watts is doable.

More involves owning another car.

Always be in Ready.

 

Not really.

Unless you want to add your own DC-DC converter. You can probably take something like 6A out of hybrid battery without causing a problem so you could add your own 200…250V DC to 14.4V DC converter with output current limited to about 80A. Or more (maybe even or double quadruple) depending what is the actual limit of how much power you can take from hybrid battery without causing fault code. Probably would be better to keep the other 12V system separated from the factory 12V system.

 

First of all, adding 10 batteries or 100 will not make a difference. The 12V system is powered by a DC/DC converter within the Prius. The 12v battery provides no power to your 12v components, even if you are pulling the full 100Amps allowed by the DC-DC converter. That being said, adding a capacitor would be beneficial.

Even if you had 3,000w worth of amps, I would not foresee you having any issues blowing the 100A dc/dc fuse. Even if you were to pull all 3,000w from those amps, you are talking about possibly a few miliseconds. Even if you have your volume maxed out and subs pumping, you are not drawing 3,000w through the whole song, only at the peaks of and only a few miliseconds at a time. You would need to try really really hard to blow a 100Amp fuse with any amount of amplifiers and speakers. Add a 2 farad capacitor and if you DO somehow come near the limits of the DC/DC, the capacitor might help the voltage from dropping.

What you are thinking is that a Prius uses an alternator. In cars that have alternators, lets say it has a 100A alternator and you are drawing 90amps from it...The voltage is going to drop near the battery voltage at which point the battery will actually be supplying the power to your amps. In the Prius, the DC/DC converter voltage will not faulter at 100 amps thus the battery will never power your system.

 

Some PriusChat members (at least Bob Wilson if I recall, and possibly also hobbit) did the obvious tests several years back, and found that the Prius DC/DC converter output voltage does indeed fall off near full output, which was around 100 amps. It would be odd if it didn't; they sized the thing to cover the expected loads.

It also has a "help! draw less current!" output that it asserts (on a circuit labeled IDH) when it is close to its output voltage falling off. The HVAC computer watches that signal and sheds the electric heat if necessary. I don't think anything else in the car from the factory pays attention to it, but I might, if I were adding a heavy load.

-Chap