DC-Converter specs

I think it is 100 amps out to the 12 volt battery for charging and car load. I set up my 2010 with 1400 watt inverter and can get about 1000 watts AC with 13.2 volts DC at the little 12 volt battery with car ready and in park. I used an electric heater for a load. I hope that helps you.
I think car alone needs 200 watts in ready mode

 

I have 3 30 amp fuses in parallel. I am waiting for a power outage to find out if it was all worth it. My unit plugs into 2 50 amp plugs in parallel. so no problem with current.

 

If you don't want to use fuses, marine (boat) parts stores usually have a good selection of high amperage 12 VDC circuit breakers.

 

That may be the best way to go. I think 100 amps or less is ok because the converter fuse is 150 amps and you don't want to blow that.
I burned out 3 fuses so far.

 

Ya think maybe that blowing the fuses might indicate a problem?
I mean, just MAYBE.

 

The problem of blowing out the fuses was 2 fold. First I put a greater load than the fuses were rated at,90 amps. and second I was using fast blow fuses with no time delay. They would still be ok if my curent demand would have stayed under the 90 amps. I was monitering the DC voltage into my 1400watt inverter when I put an additional load on the unit. The 13.8 fell below 13 volts and then the fuses blew.I wanted to see where the prius inverter could not keep up to the demand of the 12volt system.
I found if you stayed under 800 watts out of the inverter,in my case,the prius would maintain the 13+ volts to maintain the system. This value will be different depending on the efficiency of your 12volt to 120volt inverter.
I am still waiting for a good reason to use it. Larry

 

You don't say WHY you need the 12V power, but if you're looking for more than 1kW, this article may be helpful. You can get modules that will convert voltage from the traction battery down to 12V with almost unlimited current.

More 12VDC From the Prius

Richard

 

Using fuses in parallel is not exactly additive. Since each fuse has its own current path, the total resistance of each path (fuse resistance plus wire resistance plus connection resistance) will never be exactly equal. The path having the least resistance will have the most current flowing and that fuse will blow first. Granted this should be a minor effect if the wiring and fuses are kept identical, but the effect is to somewhat lower the capacity of the 3 fuses in parallel. Obviously when the first fuse blows the others will follow nearly instantaneously. The only way around this is to use a single fuse rated at the total current required or to expect the parallel combination to blow at a lower current based on how close to equal in resistance the three legs of the circuit are.

 

Thanks for the information. It is much appreciated. I was hoping the current to blow the fuses in parallel would be lower than the total. That seems like it gives me greater protection .
To answer the question , what am I going to use this for?,
I am a Ham radio operator since 1957. We have events and on one of the events we simulate an emergency and set up radios for a weekend and operate 24 hours on emergency power all for the reason to hone our operator and equipment skills . My prius may well serve as an almost KW source of 120 volt AC power.
The other reason is,
We have storms that can put out the power. The amount of power I can get from my prius can keep my gas furnace, refrigerator,a few lights and a TV going . But so far we haven't lost power in Green Bay.
If we loose power and I kick in the prius I have spare fuses and 6 gal of gas on standby. I hope we don't need it for long. If I get to use it I will update this post.
Larry

 

The link I put in my post for getting more 12V power was originally intended to power a ham transceiver without overloading the rest of the system. The Prius can supply about 3kW average by taking power from the traction battery and converting it to AC at 120 or 240V. It can also supply a lot more than that for starting up peaky loads such as well pumps and furnaces. See PriUPS.com for info on this.

The note about not putting fuses in parallel is well taken. The resistance of the fuse and fuse holder and wiring determine which fuse carries the most current. Without (wasteful) equalizing resistors, even tiny differences (milliohms) make this a dicey proposition.

Richard

 

Just to fill in this thread with the actual answer to the question in the first post, the 2010 New Car Features manual is where you find that spec for the third gen Prius.



The rating is 120 amps. Naturally, you don't get all of that for car-modding purposes; the car itself uses some of that!

My understanding is the car may use on the order of a few hundred watts in typical circumstances. Let the electric supplemental heat come on, and that can be another 700 watts on top.

The converter has an output signal, IDH, that it can use to say "hey! getting overloaded here", and the HVAC controller watches that output and can disable the supplemental heat in response.

Owners who will be adding large loads might consider also monitoring that signal.