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Cobra CPI 1575 1500 Watt 12 Volt DC to 120 Volt AC Power Inverter
See it at Amazon.com for $189.95Average Customer Rating
(4.5 out of 5)
Amazon Customer Reviews
Most Helpful First | Newest First | + ShareGreat price, fast delivery, quiet , works
(4 out of 5) by Joseph Mattioli on Nov 25, 2009Item is quiet and has low no load current draw. Mine was <.2 amp battery draw when on and 0 when off. Worked as advertized but you cannot measure AC voltage with a cheap meter as it will read 20-30 VAC low because of the modified sine wave. The documentation is barely adequate in that it doesn't answer the most common questions. One has to go on-line to the Cobra site. Also the Power out in watts doesn't indicate until you get over 100 watts and then only in multiples of 100 with the display showing only 2 digits ie: 10 =100 20 =200 etc. Documentation did not explain this or I would have given it 5 stars. Also it doesn't work on a small craftsman floresent shop light. It won't light the bulb. Only blinks. I suspect there are other limitations because of the modified sine wave but I am happy with the price for the quality. I choose it over the cheap harbour freight models that had poor reviews for about the same price. My next inverter will be a pure sine wave inverter as even though this one says 3000 watt peak, it will still not start larger than 1/2 HP motors that fall within its specs. The documentation does confirm this.
cobra cpi 1500
(5 out of 5) by Reginald Smith on Oct 26, 2009very efficient and quiet. i have used many inverters in the past but this brand is what i will buy from now on.other brands' fan starting to go right away contributing to drainage of your battery.the cobra cpi 1575 starts only when it needs to and i am yet to see it heat up for a need for the fans to come on.buy this model and you'll not be dissappointed.
1 of 1 people found the following review helpful:
Works Flawlessly
(5 out of 5) by Michael Mahoney on Oct 12, 2009 (Carroll, Maine USA)I used this every day for a week at my remote cabin. I had loads that varied from 40 watts to 1750 watts. The inverter works great and the display is accurate.
5 of 5 people found the following review helpful:
Lasted less than 24 hours
(1 out of 5) by Robert S. Dimm on Oct 7, 2009 (Kona, HI USA)Other reviewers don't seem to have had the problem I did, so this might be a good product but I must tell you my experience with it. I am very familiar with inverters and how to hook them up having lived off of solar power now for over ten years. When I first set up this inverter, the input voltage showed 12.3 volts, the same as my battery voltage but undr a 110 watt load the output wattage meter showed 0 (zero) watts. What I had plugged into the inverter was working fine (a small TV), so I assumed this meter was just broken. If that was all that was wrong I could have lived with it. The next morning I turned it on, turned on the same TV and within 20 minutes the picture on my TV slowly shrank down to a pinpoint and then shut off. There were no low voltage warning sounds. I checked my battery level and it was at 12.2 volts, the same 12.2 volts showed on the input meter on the inverter, output still showed zero, as it always did. I checked the output at all three of the outlets on the inverter and they showed zero. I turned the inverter off and then back on with the voltage meter still in one of the outlets and watched my meter go from 119 volts down to 30 volts, up to 80 volts and then back to zero. The whole time there were no warning sounds coming from the inverter. This fluctuation could very easily damage anything that was plugged into the inverter!!!!
The good news, Amazon's return system is very easy, didn't cost a penny to return it and I got a refund quickly. I thought of getting a replacement instead of a refund because of all the good reviews but decided not to press my luck, no equipment was damaged this time but why risk it again. If I could rate Amazon I would give them five stars but the inverter gets zero xtars since it didn't function as advertised, went dead under much lower load than it is rated for.
The good news, Amazon's return system is very easy, didn't cost a penny to return it and I got a refund quickly. I thought of getting a replacement instead of a refund because of all the good reviews but decided not to press my luck, no equipment was damaged this time but why risk it again. If I could rate Amazon I would give them five stars but the inverter gets zero xtars since it didn't function as advertised, went dead under much lower load than it is rated for.
5 of 6 people found the following review helpful:
12VDC Wire size and fuse considerations
(5 out of 5) by D. Warwick on Oct 4, 2009 (NC USA)This review is in response to some comments regarding wire and fuse size selections for this inverter and others like it.
In response to other review quoting a table from the National Electric Code (NEC). While the table that was posted is correct for 115VAC (household voltage) is does not translate directly to 12VDC (automotive voltage). When dealing with a 12 volt system there is less concern with wires overheating, at least in the way that the NEC considers it, and far more concern with voltage drop. When running wiring a reasonable distance (a couple hundred feet or so) there is little concern with voltage drop with AC power. But when dealing with DC, simply increasing your wiring distance 5-10' can have a drastic effect on voltage drop. That is why this inverter should be wired with, at the very least, #4 wire and really should be installed with #2 or thicker, especially if you need to run wire 15 or 20 feet or more.
The purpose of a fuse in a DC system is to protect the rest of your electrical system in the event of a short. That is why you always want to install your fuse as close to the battery as possible (no more then 3' if you can help it). As far as the amperage goes, there is a really good quick reference chart for automotive wire size that can be found at Tessco's web site here:[Turns out I can't link to an outside page so I'll paste the contents of the table at the bottom]. But to boil it down, you can safely fuse a 12VDC circuit at 150, or 200 amps, or more on #4, #2 or #0 wire.
Now this unit at full load is something like 85% efficient. So if you do the math -- 1500 Watts / 12 Volts / .85 efficiency = ~147 amps, A 150 AMP FUSE IS REQUIRED. If you take peak power into account you would need to double that to a 300 amp fuse, but because the inverter cannot run at peak power for more then a moment, a slow-blow 150amp fuse may work just fine, or perhaps you could step up a 200amp. I wouldn't go all the way to a 300 amp fuse unless you really found that you needed it and had the inverted is wired in such a way that it could handle that level current (read: installed using very heavy gauge wire). Now if your vehicle is running while your inverter is working the amperage will be a little lower because your dealing with 14.4 VDC rather then 12 volts (watts = volts x amps -or- amps = watts / volts). But at the very least, a 150 amp ANL fuse is very good idea and not at all over sized.
Just a FYI on fuses, most car stereos are installed with AGU style fuses, but they only go up to 100 amps.
You will need an ANL style fuse to get one rated at 150 amps or more. See these links for examples:
Kicker 09ANL150 150 Amp ROHS Compliant ANL Fuse - Package of 2
Scosche EWFH Single ANL Fuse Holder
Wire Gauge Selection Table 12 Volt Circuit
Wire Distance
AMPS 3' 5' 7' 10' 15' 20' 25'
---------------------------
<5 18 18 18 18 18 18 18
6 18 18 18 18 18 18 18
7 18 18 18 18 18 18 18
8 18 18 18 18 18 16 16
10 18 18 18 18 16 16 16
11 18 18 18 18 16 16 14
12 18 18 18 18 16 16 14
15 18 18 18 18 14 14 12
18 18 18 16 16 14 14 12
20 18 18 16 16 14 12 10
22 18 18 16 16 12 12 10
24 18 18 16 16 12 12 10
30 18 16 16 14 10 10 10
40 18 16 14 12 10 10 8
50 16 14 12 12 10 10 8
100 12 12 10 10 6 6 4
150 10 10 8 8 4 4 2
200 10 8 8 6 4 4 2
In response to other review quoting a table from the National Electric Code (NEC). While the table that was posted is correct for 115VAC (household voltage) is does not translate directly to 12VDC (automotive voltage). When dealing with a 12 volt system there is less concern with wires overheating, at least in the way that the NEC considers it, and far more concern with voltage drop. When running wiring a reasonable distance (a couple hundred feet or so) there is little concern with voltage drop with AC power. But when dealing with DC, simply increasing your wiring distance 5-10' can have a drastic effect on voltage drop. That is why this inverter should be wired with, at the very least, #4 wire and really should be installed with #2 or thicker, especially if you need to run wire 15 or 20 feet or more.
The purpose of a fuse in a DC system is to protect the rest of your electrical system in the event of a short. That is why you always want to install your fuse as close to the battery as possible (no more then 3' if you can help it). As far as the amperage goes, there is a really good quick reference chart for automotive wire size that can be found at Tessco's web site here:[Turns out I can't link to an outside page so I'll paste the contents of the table at the bottom]. But to boil it down, you can safely fuse a 12VDC circuit at 150, or 200 amps, or more on #4, #2 or #0 wire.
Now this unit at full load is something like 85% efficient. So if you do the math -- 1500 Watts / 12 Volts / .85 efficiency = ~147 amps, A 150 AMP FUSE IS REQUIRED. If you take peak power into account you would need to double that to a 300 amp fuse, but because the inverter cannot run at peak power for more then a moment, a slow-blow 150amp fuse may work just fine, or perhaps you could step up a 200amp. I wouldn't go all the way to a 300 amp fuse unless you really found that you needed it and had the inverted is wired in such a way that it could handle that level current (read: installed using very heavy gauge wire). Now if your vehicle is running while your inverter is working the amperage will be a little lower because your dealing with 14.4 VDC rather then 12 volts (watts = volts x amps -or- amps = watts / volts). But at the very least, a 150 amp ANL fuse is very good idea and not at all over sized.
Just a FYI on fuses, most car stereos are installed with AGU style fuses, but they only go up to 100 amps.
You will need an ANL style fuse to get one rated at 150 amps or more. See these links for examples:
Kicker 09ANL150 150 Amp ROHS Compliant ANL Fuse - Package of 2
Scosche EWFH Single ANL Fuse Holder
Wire Gauge Selection Table 12 Volt Circuit
Wire Distance
AMPS 3' 5' 7' 10' 15' 20' 25'
---------------------------
<5 18 18 18 18 18 18 18
6 18 18 18 18 18 18 18
7 18 18 18 18 18 18 18
8 18 18 18 18 18 16 16
10 18 18 18 18 16 16 16
11 18 18 18 18 16 16 14
12 18 18 18 18 16 16 14
15 18 18 18 18 14 14 12
18 18 18 16 16 14 14 12
20 18 18 16 16 14 12 10
22 18 18 16 16 12 12 10
24 18 18 16 16 12 12 10
30 18 16 16 14 10 10 10
40 18 16 14 12 10 10 8
50 16 14 12 12 10 10 8
100 12 12 10 10 6 6 4
150 10 10 8 8 4 4 2
200 10 8 8 6 4 4 2