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I have a VECTOR power inverter that I would like to install in my RAV4. Does anyone has any idea of a good place that can be wired with a high amperage cables from the battery? My inverter is 1500Watts and the OEM inverter is 300Watts, nevertheless I would like to know where do they mount OEM unit?
 

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A couple rules of thumbs with inverters. One is to mount as close to the battery as possible. this gives you less loss from wire resistance and associated heating due to the monster current running through them. Another to evaluate demand on the battery and alternator is to take the wattage used divided by 10 to get a high side estimate on amp draw from the system. So if you were running it at 1500w, you could expect that the current draw from the battery is 150 amps. In actual fact it will be less than that as the formula is Power/voltage=current, so 1500/12=125. Since we don't know the efficiency of your unit, rule of thumb gives you a pretty safe margin. That said, 125 amps is serious draw and really taxes a system. I think I have read that the standard RAV alternator is rated at 100 amps and that the tow package alternator is rated at 150. You should have enough alternator capacity to keep ahead of the inverter. If you draw more current than the alternator can supply, the battery will drain even with the car running. And the alternator will not likely put out 150 amps at idle. And if idling and you whack it with big current draw, you might see the engine speed get pulled way down from the load.

Usually when the inverter claims to be a 1500 watt unit, in reading the fine print you'll find that to be the intermittent rating and continuous is usually around 800 or so. This brings to mind the cabling you should use. I think the 1500 watt unit from doing the math will require minimum 8 gauge, but the manufacturer will want you to use 6 gauge wire at a minimum. Pretty sure that is bigger than the cables used by the RAV to operate itself. I would personally look at the realistic load I planned on running and fuse a bit higher than expected actual draw and well below the max rating of the inverter.

If you ever worked with 6 gauge or larger wire and all the fittings and fuse holders and such, you know it is big and stiff. It has to be big to handle the current. Good luck. A good place to get the wire and fittings is a vendor who deals in high power automotive sound systems.

I'd feel I was pushing the envelope with a 1500 watt inverter in a Rav4. Good luck
 

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Mike -

I'm looking to eventually add an inverter as well. You said you've done a couple of these so where did you put the inverter? Behind the dash somewhere, under the seat, in the engine compartment? Also, what guage wiring do you think would be sufficient with a 800-1000w inverter? I'm probably gonna have someone help me put it all in but just want to learn about what works good and what not first. Thanks.

Chad
 

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cougar548 said:
Mike -

I'm looking to eventually add an inverter as well. You said you've done a couple of these so where did you put the inverter? Behind the dash somewhere, under the seat, in the engine compartment? Also, what gauge wiring do you think would be sufficient with a 800-1000w inverter? I'm probably gonna have someone help me put it all in but just want to learn about what works good and what not first. Thanks.

Chad
chad

The two I installed inside the vehicle were 300w so did not have the demands on the system that yours will. One was in a pick-up mounted on the back cab wall behind the seat. the other was in a Ford explorer used for police work and the converter was out in the open on the center console. Both where the air can flow around them easily. My experience with a 1500 watt inverter was from a friend who got one and wanted to install it in his car. That is when I did the research and found out how demanding they are on the system. Ultimately he used it in a portable emergency power setup abandoning the install in his vehicle.

A high current inverter is a tough problem because you want it to be where the air can flow freely through it, but it needs to be where it is out of the elements and away from flammable materials, so the obvious location in the engine compartment is not really great unless you can protect it from the elements. Inside the passenger compartment is a problem because it will get hot when used near its potential. So you don't want it near carpet or under a seat where it can't breath. The small storage bin behind the back seat in the 4.3 Rav might be an option if you can vent it, but a high current inverter is always going to be problematic in a car.

1000 watts using the rule of thumb will use 100 amps or a bit less. So you would need AWG#6 in open air and bigger if enclosed. Most of the inverter makers will tell you to use AWG#2 or 4 for wire lengths of 10 feet or less . I guess they want a good margin of error in there. If it were me I'd use more wire thickness than I need and fuse it a bit below the inverter capacity. That way your wire won't overheat and you will disable the circuit before you get up against your max limit.

I would look hard at how you use it and not get more inverter than you need. Also be aware when considering how you will use it that some AC equipment like a nice clean signal and will work better with a true sign wave inverter as opposed to inverters that are really stepped square wave. Electronic loads like radios, stereos, computers are not going to like a dirty signal. They also have a small start up current compared to things like motors or refrigerators etc.

If I wasn't familiar with electricity, I'd definately have someone who knew what they were doing help me. Do it wrong with a big inverter and you could have a fire. A melted wire across a fuel line could be a bad situation.

Good luck.
 

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Mike -

Thanks for the info! Don't worry, I'm not going to do it myself but I at least wanted to be a little informed before I went to someone to ask them to help. You have definitely got me thinking about a few things and I'm going to be checking my electric demands and will see what the lowest I can go is.

Chad
 

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I wouldn't say 1500 watts is pushing it at all in most cases. If you plan to draw 1500 watts continuously, then yes, it is. Your starter probably draws 2-3 times that much, so it's no big deal for the battery.
 

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Hi Andrew

I would guess that the RAV starter probably draws less than 150 amps, but I could be wrong. Car batteries are designed to produce mass amounts of current for short periods of time. They have thin plates so that they can have a lot and consequently provide a lot of current, but because of the thin plates they don't do well producing heavy current for long periods of time. If you look at any of the manufacturers literature for a 1500 watt inverter you will see them telling you to use 4, 2 or sometimes even 0 cable. That is serious cable much heavier than the RAV's main battery cables. It is good engineering practice to wire the device to handle its design current. If you install a 1500 watt inverter and use undersized cable because you never plan to run it at max, if someone else does or you make a mistake and run it too hard, then the wire will overheat. Enclosing the wires as you will most likely do will downgrade their current rating. The rule of placing the inverter close to the battery is tough because you also must protect it from the elements, so finding places inside the car that allow it to breath, not near flammable material and not having too long a cable run is problematic.

I stand by my assertion that high current inverters in the RAV are trouble brewing.
 

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That works. Most of the power drawn by the inverter is from its load. So if you limit your load to 400 watts except for a brief startup draw, you would be OK to use the bigger inverter. Just don't load it to its theoretical limit. Maybe fuse the 120 VAC line at 4 amps.

Pay close attention to what MotoMike said about the 12 volt wire wire as well as his other cautions..
 

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MotoMike said:
Hi Andrew

I would guess that the RAV starter probably draws less than 150 amps, but I could be wrong. Car batteries are designed to produce mass amounts of current for short periods of time. They have thin plates so that they can have a lot and consequently provide a lot of current, but because of the thin plates they don't do well producing heavy current for long periods of time. If you look at any of the manufacturers literature for a 1500 watt inverter you will see them telling you to use 4, 2 or sometimes even 0 cable. That is serious cable much heavier than the RAV's main battery cables. It is good engineering practice to wire the device to handle its design current. If you install a 1500 watt inverter and use undersized cable because you never plan to run it at max, if someone else does or you make a mistake and run it too hard, then the wire will overheat. Enclosing the wires as you will most likely do will downgrade their current rating. The rule of placing the inverter close to the battery is tough because you also must protect it from the elements, so finding places inside the car that allow it to breath, not near flammable material and not having too long a cable run is problematic.

I stand by my assertion that high current inverters in the RAV are trouble brewing.
Yes, it needs big, short wires to handle the high current. Otherwise the inverter safety will annoyingly shut it off from the voltage drop. A big inverter isn't much of a problem as long as the average draw isn't high wattage for long, and a small inverter won't start a lot of things with a low average current but high starting current.
 

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andrewcj said:
Yes, it needs big, short wires to handle the high current. Otherwise the inverter safety will annoyingly shut it off from the voltage drop. A big inverter isn't much of a problem as long as the average draw isn't high wattage for long, and a small inverter won't start a lot of things with a low average current but high starting current.
True.

But it should be wired to handle its design current. When you use a big inverter and wire it as it should be wired, it is a royal pain. #2 wire with insulation is close to a half inch in diameter, the conductor alone is a quarter inch. AWG#0 will be probably larger than a half inch with insulation, the conductor being a third of an inch in diameter. Automotive wire of that size is stiff and difficult to deal with. You can use welding cable which is more flexible or the fancy wire that the big watt stereo systems use, but they are pricey.

It can be done, no doubt about that. If I didn't need that capacity, I'd get no more inverter than you need. I'd wire it a bit heavier than needed and fuse it just below the inverters capacity. If I had it in the car, I would watch its temp when using it heavy. Most are temp and voltage and over current protected.

You should always use good engineering practices when doing electric work, but low current is more forgiving and mistakes might not damage things. It needs to be right with something that can draw 125 to 150 amps. I think the big inverters were conceived to power electrics in an RV where you typically have a battery isolator and draw from a deep cycle battery or two and the unit is mounted in a compartment designed for it. Good luck.
 

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Just ran my heavy duty yellow extension cord 3 12# wires through the engine compartment on my 4.3. I just removed the washer fluid hose for the back window and the thing ran through the rubber grommet perfectly. Running a 1500 watt cobra for under $100. It charges laptop very fast almost worrisome in fact and also run a 6amp battery charger for a marine/rv battery. Battery charger puts it hard to work but it doesn't seem to be melting down hopefully. Ventilation is a must.
 

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A couple rules of thumbs with inverters. One is to mount as close to the battery as possible. this gives you less loss from wire resistance and associated heating due to the monster current running through them. Another to evaluate demand on the battery and alternator is to take the wattage used divided by 10 to get a high side estimate on amp draw from the system. So if you were running it at 1500w, you could expect that the current draw from the battery is 150 amps. In actual fact it will be less than that as the formula is Power/voltage=current, so 1500/12=125. Since we don't know the efficiency of your unit, rule of thumb gives you a pretty safe margin. That said, 125 amps is serious draw and really taxes a system. I think I have read that the standard RAV alternator is rated at 100 amps and that the tow package alternator is rated at 150. You should have enough alternator capacity to keep ahead of the inverter. If you draw more current than the alternator can supply, the battery will drain even with the car running. And the alternator will not likely put out 150 amps at idle. And if idling and you whack it with big current draw, you might see the engine speed get pulled way down from the load.

Usually when the inverter claims to be a 1500 watt unit, in reading the fine print you'll find that to be the intermittent rating and continuous is usually around 800 or so. This brings to mind the cabling you should use. I think the 1500 watt unit from doing the math will require minimum 8 gauge, but the manufacturer will want you to use 6 gauge wire at a minimum. Pretty sure that is bigger than the cables used by the RAV to operate itself. I would personally look at the realistic load I planned on running and fuse a bit higher than expected actual draw and well below the max rating of the inverter.

If you ever worked with 6 gauge or larger wire and all the fittings and fuse holders and such, you know it is big and stiff. It has to be big to handle the current. Good luck. A good place to get the wire and fittings is a vendor who deals in high power automotive sound systems.

I'd feel I was pushing the envelope with a 1500 watt inverter in a Rav4. Good luck
Very well written, I would not have responded with my much shorter note if I had seen yours first.
 

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Very well written, I would not have responded with my much shorter note if I had seen yours first.
Thanks for bringing this very helpful thread to my attention. I'm making it a sticky.
 
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