Interview Questions.

Question 1. How Much Power Will My Inverter Draw? I Left My Inverter On All Night And Now Nothing Works?

Answer :

The electricity required to run an inverter is approximately eight-10% greater than the power load of the home equipment being run. This is due to the performance of the inverter. These days, fine inverters are between 90-92% efficient. An smooth formula to apply to training session how a great deal DC Amps you will use out of your battery is, truely divide the AC wattage of your appliance by 12 (or 24 if a 24v device) and times this wide variety by using 1.1 to get a totally close estimate of the DC draw.

Inverters will draw electricity out of your batteries when now not in use, and the unit is became on. This can vary from around .02 amps right up to 2 amps depending on the unit and design in their standby systems in case you leave your inverter grew to become on without a load connected, the average draw from your batteries may be 1 amp in step with hour; 24 amps in step with day; or 168 amps over per week. The simplest technique to that is to simply turn the inverter off while now not required because the battery drain then becomes zero. Many of our inverters function popular or optionally available remote on/off controls.

Question 2. What Size Batteries Do I Need?

Answer :

The simple technique of running this out, is to find the largest steady AC load you intend to run from your inverter (in maximum cases a microwave is the biggest equipment), and divide this wattage x 5 (20% of your load). This will provide you with a rough concept of the way tons battery capability you require to sustain your masses. With the instance above, the microwave attracts round a thousand watts AC, so a battery bank of around 200amp hours might be required.

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Question 3. What Size Inverter Do I Need?

Answer :

Sizing your inverter is a hard project, and isn't made any less difficult by exclusive manufacturers and producers score the power in their gadgets at specific temperature scores. The power output of an inverter is dramatically decreases as its internal temperature rises, that is every so often referred to as its five, 10 & 30 minute rating; however in fact if the inverter can not eliminate the heat short enough, then the output energy will swiftly drop off. Many of the inverter brands in the marketplace are rated to deliver complete output energy up to 25°C and start to de-fee the output power from this point on. Some commercial fashions with deliver full output upto a surprising 40°C.

Basically, upload up all of the AC hundreds you want to run, then decide in case you need to run all of these objects on the identical time. If now not, select the largest load in the gadget and size the inverter 50% extra to cover top surge hundreds.

Question four. What Happens If Someone Plugs An Appliance In That They Shouldn’t Have?

Answer :

The tremendous benefit of the power inverter is its capability to surge to energy output degrees well in excess of its normal continuous ratings. These tiers are usually two times the regular output electricity for 1-2 seconds to permit for starting of large or inductive kind loads. If the burden is just too massive for the electricity output (e.G someone connects a hair dryer to a 500watt inverter), then the inverter sincerely shuts the energy down. Depending on the inverter, an audible alarm will sound, or the inverter will truly restart to attempt the weight once more. Always keep for your thoughts that a power inverter has boundaries, particularly its power length.

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Question five. What Inverter/length Do I Need To Run My C-pap (respirator) Machine?

Answer :

For C-pap machines to feature effectively they require a natural sine wave strength output. These machines have a tendency to attract around 200watts, which equates to 18amps in keeping with hour. For a normal night of sleep (7-eight hours), you would need a battery financial institution of round 200amp hours (and a suitable recharging gadget). The ePOWER 400watt inverter is perfect for fundamental C-pap machines; touch us for information in case your machine has a heater built in.

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Question 6. My Inverter Is Running Very Hot, Is This Alright?

Answer :

Power generation creates warmness, so sure your inverter gets heat. For this cause it's far essential to preserve your inverter in a place that is cool and dry, and set up in an orientation in order to assist help with air flow (e.G. You are not blocking off the intake vents or enthusiasts with clothes or equipment). If your inverter receives too heat, it's going to actually shut down until the unit cools down. As cited above, the hotter your inverter receives, the less AC power it'll deliver (hence the brand new designs including Proteins that permit for fast removal of heat air from the inside workings).

Question 7. When Using My Television Off The Inverter, There Are A Number Of Fuzzy Lines Across The Screen?

Answer :

Again a result of the use of a modified sine wave inverter. Many home equipment react to this type of waveform (which includes televisions producing lines throughout the screen, or radios having a hum through the audio system). There is not a notable deal you could do to prevent this besides to improve pure sine wave inverter. Try twisting the battery cables collectively and then wrap them in alfoil, in addition to moving the inverter as a long way far from the interfered appliance as possible (these are simply tips and might not paintings in each case).

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Question eight. Can I Run My Computer / Laptop From An Inverter?

Answer :

Modified sine wave inverters can be used on either a pc or pc, however if the pc is to handiest ever be powered from the inverter then a natural sine wave inverter (along with the POWER or ePRO) should be used, because the changed sine wave inverters will definitely smash the pc battery %.

Question nine. What Is An Inverter?

Answer :

An inverter takes DC energy (from a battery or solar panel, as an example) and converts it into alternating contemporary (AC) "household" electricity for running electronic device and appliances.

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Question 10. Why Are They Called Inverters?

Answer :

Originally converters had been huge rotating electromechanical devices used to convert AC to DC. It is what you have to do in case you don't have semiconductor or vacuum tube rectifiers. Essentially they combined a synchronous ac motor with a commutator so that the commutator reversed its connections to the ac line exactly twice consistent with cycle. The results are ac-in dc-out (with a whole lot of switching noise thrown in). If you invert the connections to a converter you positioned dc in and get ac out. Hence an inverter is an inverted converter.

Question eleven. How Is An Inverter Different Than A Ups?

Answer :

A UPS normally consists of the inverter, battery and battery charger in one stand-alone unit. However, there are UPSs that use outside batteries, and Power Stream has made inverters with battery chargers, so the variations blur as features proliferate.

UPSs also can have verbal exchange with the device that it's miles powering, which we could the device understand that it's far working on standby, giving it shutdown warning, or communicating with the human within the loop. Inverters usually don't have this conversation.

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Question 12. What If I Want A Dc Output To Run Such Things As A Laptop From A Car Cigarette Lighter, Or Telephone Equipment At -forty eight Volts?

Answer :

Then you need a DC/DC converter. Power Stream has many DC/DC converters just for the ones purposes.

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Question thirteen. What Is The Difference Between Sine Wave And Modified Sine Wave?

Answer :

Alternating contemporary (AC) has a continuously varying voltage that swings from fine to bad. This has exquisite benefits in electricity transmission over long distances. Power out of your strength employer is cautiously regulated to be a perfect sine wave, due to the fact that is what obviously comes out of a generator, and additionally due to the fact sine waves radiate the least amount of radio electricity all through long distance transmission. 

On the opposite hand, a sine wave is pricey to make in an inverter, and plenty of sine wave techniques use heavy, inefficient transformers. The most inexpensive manner to make AC is to interchange the DC on and rancid--a square wave. A changed sine wave is scientifically designed to simulate a sine wave in the maximum crucial respects that allows you to work for most appliances.

It consists of a flat plateau of fine voltage, losing  to 0 for a while, then losing again to a flat plateau of terrible voltage, back to zero for a while, then returning to the positive voltage. This pause at zero volts places more power into the 60HZ essential than a simple rectangular wave does, so it is known as "modified sine wave" in place of "square wave." Because the MOSFETs best have to show completely on and completely off the burn up he least amount of warmth for the energy generated, and so smaller semiconductors and warmth sinks are wished than if you were looking to generate a actual sine wave.

Question 14. Can I Use A Modified Sine Wave Inverter For My Medical Equipment?

Answer :

For Medical gadget, oxygen mills, and so forth. Communicate to the manufacturer of the equipment. Power Stream inverters are never tested or rated with scientific device, and we don't guarantee that they'll paintings to store your lifestyles. For such packages please locate inverters which might be rated and tested for such programs.

Question 15. What About Square Wave Inverters?

Answer :

These old skool inverters are the most inexpensive to make, but the hardest to use. They simply turn the voltage from plus to minus growing a rectangular waveform. They are not very green due to the fact the square wave has plenty of strength in better harmonics that cannot be utilized by many appliances. Synchronous vehicles, as an example, use the 60Hz thing and turn the relaxation of the frequencies into heat. The modified sine wave is designed to minimize the power in the harmonics even as nevertheless being reasonably-priced to make.

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Question 16. How Do I Know If I Need A Sine Wave, Or If I Can Live With A Modified Sine Wave?

Answer :

The following gadgets paintings nicely with a modified sine wave: electric powered blankets, computers, motor-pushed appliances, toasters, coffee makers, and maximum stereos, ink jet printers, refrigerators, TVs, VCRs, many microwave ovens, and so forth.

Appliances which might be known to have troubles with the changed sine wave are some digital clocks, a few battery chargers, most mild dimmers, a few battery operated devices that recharge in an AC receptacle, some chargers for hand tools (Makita is thought to have this trouble within the beyond). In the case of hand equipment, the hassle chargers normally have a caution label stating that dangerous voltages are present on the battery terminals while charging. We would love to add to this FAQ any appliances that you have had hassle with, or had fulfillment with, using modified sine wave inverters.

Question 17. Why Do I Hear Buzzing On My Stereo When Using A Modified Sine Wave Inverter?

Answer :

Some inexpensive stereos use energy elements that can not take away commonplace-mode noise. These might require a sine wave inverter to perform noise-free. What you listen is a number of the better harmonics of the changed sine wave.

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Question 18. Why Don't I Measure Rated Voltages When Using A Multi Meter On My Modified Sine Wave Inverter?

Answer :

The rated voltage is an RMS (root suggest square--they rectangular the value to ensure it is usually high quality, then average it, then take the rectangular root of the common to make up for having squared it in the first area) dimension. Most multimeters are designed to offer accurate RMS readings whilst carried out to sine waves, however not when they're applied to other waveforms. They will study from 2% to 20% low in voltage. Look for a voltmeter that brags approximately "True RMS" readings, and as a way to read successfully irrespective of what the wave shape is.

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Question 19. How Should I Select The Right Size Inverter?

Answer :

First add up the strength ratings of all of the appliances, after which buy the next large inverter! At least that is the simple solution. Note, however, that some appliances, such as desk saws, fridges, and microwaves have a surge requirement. Power Stream inverters are designed to supply such surges, however due to the fact each appliance has its personal necessities now and again you will need to get a bigger inverter than you will otherwise suppose. Note that the inverter isn't always the only consideration when you are thinking about the mysteries of start-up surges. The battery ought to also be able to supply the surge electricity, and the cables must be able to deliver the improved cutting-edge with out losing the voltage an excessive amount of.

Question 20. How Is A Microwave Rated For Wattage?

Answer :

When you buy a microwave oven you need to recognize how intense the microwave area is, not how a great deal the oven attracts from the wall. So a microwave oven that boasts six hundred watts at the container can have an input requirement of 1200 watts on the boilerplate within the back. Don't be fooled!

Question 21. Are Stereo Amplifiers Rated The Same Way?

Answer :

Stereo manufacturers are bigger liars than politicians. Sometimes they use peak output strength (milliseconds), occasionally they use electricity drawn from the wall, but frequently they just observe the competition's cool animated film front and add 10%. However the truth is available: take a look at the boilerplate sticky label, which has been evaluated through all. This will give the most viable strength drawn, so it has a tendency to be higher than you will honestly draw.

Question 22. Why Do I Need Such Humongous Cables To The Battery When A Small Cord Takes The Ac Output Fine?

Answer :

Power is volts times amps (Watts = V x A). So when you have quite a few voltage you don't want many amps to get a watt. Roughly you want 12 instances as a great deal contemporary from the 12 volt battery as you need from the a hundred and ten volt AC outlet. Current is what causes cables to warmth up, not voltage. That is why they use hundreds of volts in long distance electricity transmission grids. The component to do when you have masses of modern-day is to lower the resistance of the cable. The larger the wire the lower the resistance. Think of the cable as a water pipe. A large pipe (cord) can bring greater water (contemporary or amperage) with much less stress (voltage), and could gift much less strain (voltage) drop from one stop of the pipe to the opposite.

Another attention is how far the cable has to run from the battery to the inverter. Long cable runs are high priced, both in copper or efficiency, or each.

Question 23. Why Would You Use A 24 Volt Inverter Instead Of A 12 Volt Inverter?

Answer :

At a given energy rating a 24 volt inverter will need half of the present day as a 12 volt inverter. This makes the whole system extra efficient, and on the grounds that excessive current transistors are pricey, the inverter might be inexpensive.

Question 24. Should I Use A Laser Printer With An Inverter?

Answer :

Only if you ought to. Laser printers use up a shocking quantity of electricity (because of the heated fusing rollers), and could discharge your battery quicker than you assume, even on standby. If you do, ensure the inverter is rated for the power of the printer plus laptop plus display. It would not do any proper to have your computer brown out as quickly as the printer starts to print. Ink jet printers, alternatively, use a highly low quantity of power.

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