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Hi all;

After Hurricane Irene, I've decided I should have a backup so if I lose power, I don't lose my basement...
I'm thinking about getting either the Powerbright 2300 watt or the 1500.

http://www.costco.com/Browse/Product.aspx?prodid=11540208&whse=BC&topnav=&cm_sp=RichRelevance-_-itempageVerticalRight-_-PurchaseCP

Are there any issues with doing such a move? I don't want to ruin my beloved "Lady B" (The nickname the kids have given the Prius).
If I connect too many devices to the inverter - could that damage anything? Can the Prius battery support such a load?

Thanks!

The traction battery likely can support that load, but the 12V system cannot. I believe the HV-to-12V inverter limit is around 100 amps, and some of that must go to the car's systems.

The small 12V battery alone, with the car not in 'Ready' mode, absolutely-positively cannot support this inverter.

I remember reading someone did that a few years ago with his Prius. He started the car which was starting the ICE only when necessary.

I don't know how he connected his inverter to his Prius nor how much power he needed. In my cars, I don't know about Prius, the biggest fuse @12V sockets is 20A, so I would need to connect such an inverter directly to the battery.

Keep the power needed low, ie switch on only what is necessary and try to find alternatives to electricity. Keep your car in a ventilated place.

I though about that myself. I heat the house with electricity, but I have a chimney I can use when I don't have electricity. I cook with gas. I have a cell phone. I have a small radio with batteries. I have 2 old car batteries that I try to keep full with a small inverter for light and other small things, such as charging the cell phone. I have a "small" 80W solar panel that may help, but electricity problems happen only during winter storms here...
The fridge and the freezer can keep food for 2 days. If needed I can connect them to the inverter connected to the spare batteries connected to my running car.

Denis.

Although I'm not an expert on Prius electrical systems in particular, I agree with fuzzy. That 2300-watt inverter would demand well over 200 amperes input at full load. You might get by with a MUCH smaller inverter (like 150 watts or less, I'd guess). The 12-volt battery alone wouldn't be able to support even that for more than a very short period.

If you need anything approaching 2300 watts of emergency power, you need a separate generator. If your explanation " ... so if I lose power, I don't lose my basement..." means you're thinking of using the inverter primarily to power a pump, a pump driven directly by an engine would be more efficient and less expensive than using an engine to power a generator to power a pump.

Sears sells a battery pack/jump unit that has a built in 12 volt support. You can run AC off it and it even has an USB for charging and an air compressor built in . It can either be charged by AC or you can get a cigarette adapter with two male ends to charge off your car.

Portable Power 1150 (http://www.sears.com/shc/s/p_10153_12605_02871988000P?mv=rr)

It might be an option available to you.

Ignore the reviews I'm betting those who were un happy with the unit didn't read the owners manual. You need to check it every two or three weeks to make sure it is at full capacity. They probably charged it and left it on a shelf for a few months and never checked the state of charge.

I have the 950 BTW and am very happy with it.

It is real hard to check it's power level, you have to push a rocker switch on the front to see the state of charge on the LED display.:p

I bought it so can jump the Volvo because it sits a lot and in case the power goes out I can plug in the laptop and watch a few movies until the power comes back on.

The larger inverters require hooking directly to the battery. I have a 2000 watt inverter that I have had hooked up. It says it will power up to 17 amps. This winter I will hook it up again. You can't run something like a water heater or a new computer controlled furnace off of these cheaper inverters. Use the proper cables for hooking up this style inverter. A bad connector or undersized cable could cause more problems than no power.

You need a pure sine wave inverteror it will either not operate the furnace or toast something on it. I would use the Prius if needed for lights etc. I have a 2000 watt Honda powered inverter/generator that I would hook up for the furnace, refrigerator, and freezer.

Hi, first off I take no responsibility for damage to one's car or voiding of warranties. That being said, however, the prius is more than capable of running a 2300w inverter hard wired to the battery terminals while the car is in ready mode. I have spoken to toyota techs regarding this very issue and have been told the prius will support a load of 30 amps from the 12 volt battery in the hatch area, providing the car is in the ready mode, where the inverter can maintain the charge of the 12 volt battery. The claims of extremely high amperage are in error, as a 12v dc to 120v ac inverter at 2300 watts will draw just under 20 amperes at peak load (volts x amps = watts). Since the inverter in the prius supplies 120 amps this is hardly a heavy load at all, but the tech felt 30 amps was a safe number, though 40 was certainly feasible. The prius will simply idle occasionally to keep the smaller 12v battery at peak charge, but will be able to do this for a very long time while using very little gas. Just remember to keep all other accessories in the car as well as lights turned off to maximize efficiency. Also, be sure the wires connecting the inverter terminals to the prius battery are sufficienly heavy gauge as to not create unneeded resistance. Good luck and enjoy your new mobile power station!!!

Hi, first off I take no responsibility for damage to one's car or voiding of warranties. That being said, however, the prius is more than capable of running a 2300w inverter hard wired to the battery terminals while the car is in ready mode. I have spoken to toyota techs regarding this very issue and have been told the prius will support a load of 30 amps from the 12 volt battery in the hatch area, providing the car is in the ready mode, where the inverter can maintain the charge of the 12 volt battery. The claims of extremely high amperage are in error, as a 12v dc to 120v ac inverter at 2300 watts will draw just under 20 amperes at peak load (volts x amps = watts). Since the inverter in the prius supplies 120 amps this is hardly a heavy load at all, but the tech felt 30 amps was a safe number, though 40 was certainly feasible. ... !
You're unfortunately confusing input and output. Assuming you're correct about 30 amperes from the 12-volt system being a maximum safe load, 12 volts x 30 amperes = 360 watts. That's power going into the inverter. Because the inverter is less than 100% efficient, its output at 120 VAC would be less than 360 watts.

What load does the OP actually want to replace?.. a water pump?

Thank you all for responding to my message. Maybe I didn't make myself clear:
I want to connect the inverter directly to my Prius battery, and run mainly the sump pump. Once the threat of water is gone, If still no power, I would connect the fridge.

I would leave the car in "ready" so the 12V battery won't deplete.

My worry is can I do any damage to the Prius by doing this?

I think MrLee's response is exactly what I'm aiming for, but I just want to be sure I won't screw up anything.

A 1/2hp Wayne sump pump is about 5 amps. What is deceptive and you need to be cautious about is the starting amperage. When started under load, the amperage could multiply for a milli-second.

The larger inverters require hooking directly to the battery. I have a 2000 watt inverter that I have had hooked up. It says it will power up to 17 amps. This winter I will hook it up again. You can't run something like a water heater or a new computer controlled furnace off of these cheaper inverters. Use the proper cables for hooking up this style inverter. A bad connector or undersized cable could cause more problems than no power.

You need a pure sine wave inverteror it will either not operate the furnace or toast something on it. I would use the Prius if needed for lights etc. I have a 2000 watt Honda powered inverter/generator that I would hook up for the furnace, refrigerator, and freezer.

Is the 200 watt inverter connected to a Prius?

It is a 2000 watt that I connect to the Prius. I work 12 hr. shifts and am gone a total of 14 hrs on the days I work. I wanted something easy for my wife to hook up, so I set it up for the winter ice storms to power a couple of lights and the blower on a gas log.

http://www.aprs.org/FD-Prius-Power.html
Try the above link

As noted above you are limited to about 1000 watts continuous as that is near the limit of the Prius converter. I can't vouch for any info in that article but it is what you are striving for so use as you feel comfortable.

From my off grid living experience you are going to find all kinds of problems operating everyday things on a modified sine wave inverter. Resistance loads are fine, others all have potential issues and you will find many variables. Some of which can be costly as the things don't always just not work but slowly get destroyed.

One of the small inverter based generators make a great power source for short term use. They can power from about a 1000 to 1600 watt AC load for many hours on a gallon of fuel. Likely less than the Prius and without any risk to the Prius. I have a Honda as do many friends and find it reliable and useful. Have over 500 hours on one i2000 and it still works fine.

Mike

You're unfortunately confusing input and output. Assuming you're correct about 30 amperes from the 12-volt system being a maximum safe load, 12 volts x 30 amperes = 360 watts. That's power going into the inverter. Because the inverter is less than 100% efficient, its output at 120 VAC would be less than 360 watts.
Actually, not at all, as voltage is increased amperage is decreased in proportion, assuming wattage remains the same. That is why a 240 volt air conditioner will draw half the amperage of a 120 volt unit if the btu remains the same. Please google "inverter amperage calculator" to see the relationship between the three factors. There is a handy web site which allows you to calculate these for yourself...www.supercircuits.com/resources/tools/Volts-Watts-Amps-Converter

Also, by way of field testing, I ran a 750 watt inverter off the prius for several hours recently, it worked great and the car was in ready (idle) mode, and it only turned on to recharge the battery pack a couple of times. The inverter was run using a plug supplied with the unit into the 12volt prius power port with no ill effects whatsoever.

The SIZE of the inverter in watts is relatively unimportant. The power continuously available from the 12 v system ( 12 X 30 = 360 watts? ) is. You can have almost any size modern inverter hooked up so long as the steady state load you plug into it is less than about 350? watts. The continuous duty load of the Prius DC ( HV ) to DC ( 12 v ) converter is unknown to me. THAT is the limiting power. It is cooled and has design parameters. Running this converter outside these parameters could damage it. The only thing you can safely say is that you can use the power that is available from the dc power sockets.
The way to really do this is an inverter running off the HVB where many kilowatts should be available but that is not an amateur users project.

... I have spoken to toyota techs regarding this very issue and have been told the prius will support a load of 30 amps from the 12 volt battery in the hatch area, providing the car is in the ready mode, where the inverter can maintain the charge of the 12 volt battery. The claims of extremely high amperage are in error, as a 12v dc to 120v ac inverter at 2300 watts will draw just under 20 amperes at peak load (volts x amps = watts). ...

Either your claim that the 2300 watt inverter will draw only 20 amps from 12 VDC is in error, or my Electrical Engineering degree and entire engineering career are in error.

RedylC94 has it right.

I repeat: Prius' 12V system will not safely support a 2300 watt inverter. Only the high voltage side, i.e. traction battery side, has that potential capacity.

Also, by way of field testing, I ran a 750 watt inverter off the prius for several hours recently, it worked great and the car was in ready (idle) mode, and it only turned on to recharge the battery pack a couple of times. The inverter was run using a plug supplied with the unit into the 12volt prius power port with no ill effects whatsoever.
What was being powered from this unit?

It is a 2000 watt that I connect to the Prius. I work 12 hr. shifts and am gone a total of 14 hrs on the days I work. I wanted something easy for my wife to hook up, so I set it up for the winter ice storms to power a couple of lights and the blower on a gas log.

Sounds like you have plenty of extra capacity for that load and your battery should be able to buffer any momentary demand surges.


I've actually pumped a lot of wells using pumps hooked up to my truck's battery. I wonder if the OP has actually tested the load from his pump...I think most of them need less than 500 watts (1/2 hp < 500 Watts). I would guess that a 1000 watt inverter would serve his pumping needs without much risk of overtaxing his car's electrical system.

Either your claim that the 2300 watt inverter will draw only 20 amps from 12 VDC is in error, or my Electrical Engineering degree and entire engineering career are in error.

RedylC94 has it right.

I repeat: Prius' 12V system will not safely support a 2300 watt inverter. Only the high voltage side, i.e. traction battery side, has that potential capacity.


What was being powered from this unit?

I was running a pc/ router, modem, a box type fan, lights, and recharging all my devices, such as phones, ipad, etc. Perhaps I was unlear before, the prius tech was speaking of 30 amps ac draw....you do agree that as volts increase, amps decrease proportionately, yes? So 120 volts ac at 2400 watts would be 20 amps ac, is this not correct? And perhaps it is irreponsible on the manufacturers part, but if a 750 watt 12 volt dc to 120 volt ac inverter draws huge amounts of dc amperage, how are these made, and used, with dc cigarette type plugs? Isnt the limit on cigarette lighter style plugs 10 amps as stated in the manual?
I guess the best way to measure these figures is with meters, which I do not have, since even drawing a mere 480 watts thru an amp plugged into the dc power would be drawing 40 amps at 12 volts dc? That would have blown my fuse immediately, but this didn't happen.

I was running a pc/ router, modem, a box type fan, lights, and recharging all my devices, such as phones, ipad, etc. Perhaps I was unlear before, the prius tech was speaking of 30 amps ac draw....you do agree that as volts increase, amps decrease proportionately, yes? So 120 volts ac at 2400 watts would be 20 amps ac, is this not correct? And perhaps it is irreponsible on the manufacturers part, but if a 750 watt 12 volt dc to 120 volt ac inverter draws huge amounts of dc amperage, how are these made, and used, with dc cigarette type plugs? Isnt the limit on cigarette lighter style plugs 10 amps as stated in the manual?
I guess the best way to measure these figures is with meters, which I do not have, since even drawing a mere 480 watts thru an amp plugged into the dc power would be drawing 40 amps at 12 volts dc? That would have blown my fuse immediately, but this didn't happen.

2400 watts OUTPUT of a 12 vdc input inverter will require over 200 AMPERES dc. This would require battery cable sized wires. The Prius will not provide that. Most of the loads you cite are 10's of watts except incandescent lights. I'm not aware of any inverters with cigarette plugs over 200 watts. If there are, they are unsafe.
If your talking about a 480 Watt audio amplifier, that's the maximum rated output filling an auditorium with sound. Wattage ratings on devices like inverters are the MAXIMUM they can handle. You can have a 750 RATED watts inverter on a Prius all day providing a 150 watts of load. The bigger inverters tend to have a little more no-load idle dc current than a 150 watt cigarette plug in type. The Prius 12 vdc battery can probably put out 100+ amps briefly but not for more than a few minutes. The HVB can put out 100 amps for seconds.

Thanks for the info, lolder, though I am not the original poster, I am also looking to put a bigger inverter in the prius. As I understand it, the dc-dc on board inverter (converter?) in the prius is the weak link here. The numbers on the gen 2 prius inverter were 100 amps at 12-14 volts dc output. This would be 1200 watts, conservatively. This would be used by any systems in the car active during ready mode, the rest going to the 12v dc battery in the trunk area. The gen 3 prius of which we are speaking now, is believed to be 120 amps at 14 volts dc output. This translates to 1680 watts total output in ready mode. Allowing for other devices in the car being active during ready mode, this would leave maybe 1300 watts available at the battery terminals on a constant basis. Drawing over this amount would result in the battery becoming depleted, and eventual alarms/ safeties being tripped in the prius' internal systems. However, brief spikes over the 1300 watt limit would be absorbed by the battery, assuming it is fully charged. This would explain why a previous poster stated he could run a 2000 watt inverter off his prius. His constant draw was probably not 2000 watts, but somewhat lower, with occasional spikes as refrigeratrs turned on, etc. There have been posts on other forums detailing prius drivers using 1500 watt inverters on gen 2 priuses successfully, though on person used a second battery wired in parallel with the small prius battery, and another person replaced the prius 12v battery with a higher rated optima battery. So to the original poster, my position would now be, I agree 2400 watts being drawn from a prius is not a good idea. Staying within the parameters of the on board inverter, allowing for an occasional spike as an appliance momentarily kicks on should be feasible.

You understand it correctly. The limitation is the maximum continuous rating of the Prius DC to DC converter. I would be surprised if it were 120 amps continuously. A bigger inverter than about 1500 watts would allow better management of motor starting loads so long as the steady state load was less.

More news about this subject: Cars that provide power (http://www.cleanmpg.com/forums/showthread.php?t=40750)

I was running a pc/ router, modem, a box type fan, lights, and recharging all my devices, such as phones, ipad, etc.
How many watts? Depending on the details, these could well be very far under 750 watts. A Kill-A-Watt meter would be very handy here.

Perhaps I was unlear before, the prius tech was speaking of 30 amps ac draw....That directly contradicts what you wrote in post #7. I'm more inclined to believe the tech was speaking as in the earlier version.

... RedylC94 has it right. ...


Thank you, fuzzy (and lolder, too)! Nobody has yet invented an inverter that's 1000% efficient, as the earlier post effectively claimed. People seem to confuse output current of an inverter with its input current, and also confuse the rated maximum power with the power it is actually providing.

Remember that the sump pump motor, like many other devices, will demand an inrush (starting) current several times its rated or running current. The inverter needs to be sized to allow for that. The idea of connecting a larger 12-volt battery in parallel is probably good in that regard, too (although it sounds cumbersome!).

I think Hobbit has done something like this. If I remember correctly, about 1,000 watts is all you can do with a 2nd gen Prius.

A good inverter will shutdown if the battery voltage dips to 10V or so, then you have to reset the switch.. you have to use a good battery, clean connections and very good cables if you intend to draw a decent amount of power. If you notice the cables or connections getting warm then you need to work on that.

I have a 750w Black & Decker inverter, I feed it with three 12v 24F deep cycle batteries in parallel, using #00 cable for the hookup, and I keep the inverter very close to the batteries (18 inches).. I have used this up to 500w of output and it works well. Connector to the inverter just gets slightly warm.

what does the OP intend to power with the inverter?.. probably easier to run a generator.

How many watts? Depending on the details, these could well be very far under 750 watts. A Kill-A-Watt meter would be very handy here.

That directly contradicts what you wrote in post #7. I'm more inclined to believe the tech was speaking as in the earlier version.

As i was running the inverter it displayed about 500 watts constant draw, as to what you mentioned in #7 absolutely correct, once i took into account the on board inverter i revised the numbers in #22.

As an aside I have some experience in this sort of stuff, as I designed and installed a solar array on my house consisting of 22 panels generating 3740 watts into a grid tied inverter. My hope is to someday have a plug in hybrid or pure electric I can charge from the house, for truly free driving.