- Provides true sine wave AC current with high surge capability that provides necessary current at startup
- Dual GFCI AC receptacles and innovative USB power connection
1.) In order to handle heavy loads, high-power inverters require high-capacity battery banks and low resistance wiring and connections.
2.) Even the recommended battery/wiring system may not supply the specified voltage to the inverter for the inverter to supply its maximum rated output.
3.) The maximum rated inverter output is lower for motor loads, which are inductive.
4.) You are faced with high current surges associated with motor starting.
You may be familiar with some or all of these considerations but I'll give some details.
The SW2000 does produce a true sine wave as observed on an oscilloscope. It also maintains the 120 Volts under varying loads.
My main application is to provide minimal emergency back up power when the utility electrical service is interrupted. During a worst case scenario test we found that our SW2000 can power our natural gas central air furnace igniter and fan motor, refrigerator, lights, bathroom exhaust fans, and computers -all at the same time. But, all this does not fully load the inverter -it only takes it up to about 1200 watts. During an actual emergency, we would not do this -we would use the appliances sparingly.
But, whatever the load conditions, the user's battery supply would need to keep the input terminals of the inverter up to 11 volts to avoid the "low battery" alarm from beeping or, at very least, up to 10.5 volts to keep the inverter from shutting itself off -these features are designed into the inverter to prevent the battery charge from getting too low.
Therefore, to keep the inverter input power terminals above those minimum voltage levels under heavy load conditions, the owner's guide recommends a bank of four 12-volt deep-cycle batteries, size AWG 0 wires no more than 6-feet long, terminal lugs that are crimed super tight onto the wire ends, good condition batteries that are fully charged, and all connections tight.
In my own case, I could never expect the inverter to operate near the full, advertised load (1800 watts) because I am only using two batteries and smaller size AWG 2 wire.
But, here's a test using a heavier load than what I need: When I start with fully-charged batteries and plug a 1500-watt electric heater into the inverter, my battery/wiring system will only supply 11.4 volts to the inverter power input terminals. After about 15 minutes, the voltage drops down to the 11-volt level and the inverter beeps its "low battery" alarm. After a little while longer, the voltage drops down to 10.5 volts and the inverter shuts itself off.
This is important: when the "low-battery" alarm beeped, and later when the inverter shut itself off, THE BATTERIES WERE NOT ACTUALLY LOW and THERE WAS NOTHING WRONG WITH THE INVERTER. The problem is that my battery/wiring system is not sufficient to support the heavier, 1500-watt load for very long. The specific gravity of the battery acid did not indicate a low charge in the batteries. The inverter was not defective.
The inverter only did what it was designed to do. My undersized battery/wiring system only made it look as if there might be a low-battery or inverter problem. The 1500-watt heater overloaded my battery/wiring system. The inverter is OK. The batteries are not low. I can use our inverter-battery system successfully with our usual, smaller load -like the essential home appliances that I mentioned previously.
All of the above is not to say that there can not be hardware problems or exaggeration in advertising. I only mean to help users by conveying some of the pesky details needed to get good results.
I wish it were not so ... but ... if I needed the absolute full capacity (1800 watts) of the SW2000, I would not only buy two more batteries and larger wire, but I would buy a different model inverter with an even greater capacity -maybe 3000 watts continuous.
Here's why. The devil is in the details. On page 17 of the owner's guide, the 1800-watt rating is shown in the power output chart along with an input of 13 volts! Wow! Their test facility must have a monster power supply to maintain the specified 13 volts at the inverter power input terminals while loading the inverter with the specified 1800-watt resistive load and while delivering a minimum of 140 amps (1800 watts divided by 13 volts = 140 amps).
Sorry, but I have no reason to believe that, even with the recommended bank of four batteries and large wire size, I could ever provide the specified 13 volts needed to produce the specified 1800 watts from this inverter. I would expect my real-world, four-battery power supply voltage to sag down well below the 13 volts due to resistances in the wires, fuses, and connections, as well as the internal resistances of the batteries.
But wait ... there's more. In the same chart on page 17, they say that the rated 1800 watts only applies to resistive loads like incandescent bulbs [and heating elements]. But, what if you need to run motors? Then the limitation is 15 amps maximum. If you multiply the output of 15 amps by the output of 120 volts, you get 1800 watts -but only into a resistive load.
However, if your load is composed of one or more motors, you have an inductive load. When you multiply the 15-amp maximum by 120 volts, you get a maximum output of 1800 volt-amps apparent power. If the motor load has an 80% power factor, the maximum real power (to produce work) would only be 1440 watts. Also, motors usually produce a momentary current surge at start-up -a further demand upon the inverter/battery system -which it may not be able to supply.
I can see why many people are disappointed with their inverters: faulty hardware, misleading specifications, difficult applications such as motors, and inadequate input power supplies (battery/wiring).
My personal conclusions: pay really close attention to installation details and buy a substantially over-sized inverter.
Good luck.
Buy Xantrex PROWatt 2000 Inverter, Model# 806-1220 Now
I see a few complaints in the reviews about having trouble with high-load applications of this inverter. I bought one about a year ago, with the intent of using it to get solar-powered air conditioning in my RV. I made it work, eventually, and the problems I encountered had nothing to do with the inverter (which supplied 1500 watts sustained load and handled the surge of starting the AC, once I got everything else working).First of all, wiring: Everything will tell you that 4 gauge should be more than big enough: Not even close. I tried 4-gauge. Then I tried 0-gauge. Then I tried making the wire runs shorter. Then I started doubling up wire runs in parallel. By the time I was through, my battery interconnects were double and triple 4-gauge in parallel, and the connection to the inverter (coming from the center battery of 5) was 000-gauge (also known as 3/0). Connecting that to the terminals on the inverter required taking an industrial terminal block normally used for substation wiring and drilling a 3/8" hole to connect it to the terminals. Finally I had something that wouldn't drop 2+ volts over the wires when drawing 125 amps. When they say 4 gauge can pass 200+ amps, they mean that it won't melt the wire, not that it will give you a usable voltage.
On top of that, batteries: Lead-acid batteries may say they can deliver huge numbers of amps, but not without huge voltage drops. In practice, for every amp you're drawing you want at least 2 pounds of battery (so, minimum 4 size 27 batteries to deliver 125 amps needed for 1500 watts). Try to power your space heater off something you can pick up assisted, and you're just going to get a lot of annoying beeps.
And don't forget that after you've drawn off half of the amp hours theoretically available in your batteries, your *maximum* voltage will have dropped to around 11.8 (so battery load and wiring losses will be working from a lower baseline). With 5 type 27's, I could run the original rooftop air conditioner for no more than 1.5 hours before they were too far down to provide 11.0 volts under load. So I figured out a way to mount a modern, high-efficiency unit that provided the same cooling for half the power.
The point here is that with a really big inverter, you're pushing 12V right to the absolute limits, and you have all *kinds* of weak points that will keep your system from working properly. These are really intended for big residential solar systems with batteries in the thousand-plus pound range. This inverter works *fantastically* well, now that the rest of the system is properly supporting it, but even for an experienced electronics tech getting all that arranged properly was quite an education.
Read Best Reviews of Xantrex PROWatt 2000 Inverter, Model# 806-1220 Here
I have been running A 1 Kw solar plant to run a 1500 watt 19 gal water heater or 2 515 watt Air Conditioners (window units). The Xantrex 2000 inverter easily runs the water heater and 1 AC unit at the same time or the 2 AC units by themselves. It won't handle the startup load of both AC units at the same time though, so I added a time delay relay to one of the AC units and now the inverter easily runs both. I am very impressed with this product after having a Sunforce 4500 watt inverter for almost 2 years now. The Xantrex is way more efficient than the Sunforce with only .8 amps of overhead. It's quiet, well built, and so efficient I can leave it on continuously. I am very pleased.Want Xantrex PROWatt 2000 Inverter, Model# 806-1220 Discount?
I use this inverter to power my small mountain cabin. Powered by 800w of solar panels and 4 Trojan t-105 batteries, it runs my Grundfos SQF well pump, lights, microwave and what ever hand power tools I need (not all at the same time). It will not start my radial arm saw, but I wouldn't expect it to. My 4kw generator struggles with starting that saw. Lots of people complaining that it's only rated for 1800 watts continuous. A thousand dollar honda eu2000, 2000watt generator is also rated for considerably less than 2kw continuous loads, both will however put out 2000 watts for motor starting surge etc. This is an industry standard. You should know your needs and research the product before you buy. It's been my experience that lack of power to the inverter (low batteries)is more of a problem than the inverter itself. If you get an alarm there is a reason, Most likely the inverter is doing what it is designed to do. The GFI is a nice feature that could save your life. My only complaint is that the shutdown voltage is so low (10.5v), at that voltage you have shortened the life of your batteries and they are far more expensive than the inverter. Note: 1800w at 12.1v (50%charge on my batteries)is more than 148 amps. That load will kill a car battery in a few minutes and you'd better have some heavy duty cables.The Xantrex Prowatt SW2000 is an excellent product some of the reviews here claim the unit does not deliver the power claimed... well if you have a good power source and 12 volts DC at the rear terminals the unit *WILL* start a 6000 BTU window air conditioner with an additional 100 watt light bulb connected to it. I measiured 26 amps surge power with a calibrated clamp-on amp meter set to peak hold that is 3100 watts output! (Spec is 3000 watts surge). I also tested 1600 watts continuous no issues there either (1500 watt hot plate + 100 watt light bulb).The unit also regulates AC voltage very well too the light barely dimmed when the AC compressor started (26 amp surge).
Users that are having issues with low power output have one of the 3 problems (Not the inverter):
1) Batteries are not able to supply the power under load
2) DC cables are too long
3) DC cable wire size is too small
Measure your voltage AT the inverter terminals and at the battery under load that will reveal where the problem is.
I used 8 cells of Lithium Iron Phosphate in a 4s-2p configuration and the cells are 100 amp hour each with under 2 milliohms ESR.... Short circuit current is north of 3000 amps! The wire was less than 1 foot long on each and thru a 120 amp circuit breaker. With 1500 watts load I still have 12.8 volts at the inverter with the batteries measuring 13 volts.
The unit is well built not some cheap design or poor construstion and should provide years of reliable operation. This is why I give it 5 stars.
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