Yacht Power Inverters - A Guide

Power inverters

Computers, hi-fi and microwave ovens use considerable power, so if you're considering using them on board you'll probably need power inverters.

An inverter is probably one of the first extras most owners consider buying for their boat, whatever size it is. The ability to use 240V equipment when you are on passage or moored away from a shore supply is prized by most people. At the same time, an inverter is one of the easiest items to install, providing you understand the basic steps involved. Inverters range in size from 50W to 4kW, and can power most items that you now plug into the mains, but you need to understand their limitations, and for that you need to understand what makes them tick.

How they work An inverter takes low-voltage direct current (DC) from batteries, usually 12V or 24V, and converts it to high-voltage alternating current (AC), either 110V, 230V or 240V. The process is the same as your battery charger, except in reverse, and some combi models double as chargers, using the same basic electronics inside. Early inverters used transformers to step the volts up, and were heavy, but most modern models use solid-state electronics, both to step up the voltage and to convert the current from DC to AC, and are correspondingly lighter.

Domestic mains supply voltage follows a sine-wave form with a rounded top as the current alternates. But, while this wave form is easily produced by a rotating generator in a power station, it's more complex and costly to produce electronically and wastes more power. Instead many inverters use a modified sine-wave, or quasi sine-wave, which has a flat topped or square curve. The modified sine-wave powers most AC equipment, but can struggle with some items, particularly electronics with internal power supplies and digital timers like computers, TVs and microwave ovens. Recently the internal power supplies for most electronic equipment have changed to switch-mode systems, which better handle poorer quality incoming AC. At the same time, the standard of the best modified sine-waves has improved markedly, close to that of a pure sine-wave.

Yacht batteries and marine batteries

An inverter can provide high outputs but all this power has to come from your batteries. Short burst high power appliances like a microwave oven, kettle, toaster or hair-dryer are fine, but to run heaters or machines for long, you need a very large battery bank or engine power.

As we have said, virtually anything that you now plug into the mains can be run from an inverter, but the size of your unit governs what it will power. Up to 500W you can run computers, TV, hi-fi, battery chargers for your mobile phone and cameras, and even a 240V domestic fridge, though not always all at the same time.

Up to 1,000W, and you can add a small travel hair-dryer. For most people however the big plus is being able to run a microwave oven and for this you will need at least 1,500W, preferably 1,800W. Don't be confused by the 60OW or 80OW rating on most microwaves. This is the useful cooking power they generate, not the amount of power going in, which will be double this figure.

And at this size, your inverter should also power a standard hair-dryer, plus possibly a kettle, toaster and coffee-maker, though these may require 2kW.

Installing an inverter is within the capabilities of a competent DIY electrician, but if you've any doubts, leave it to a professional. A 2kW, 12V inverter will be drawing up to 200A from your batteries, more than many engine starter motors, so you need large diameter cables, short runs, and good connections. For the higher output models, use 50mm cables (35mm for lower outputs), a maximum of 1.5m long with properly crimped lugs, not screw connectors as they work loose. Anything less and you could lose too much power down the line, which means reduced performance and possibly tripping the inverter. You need proper cable from a battery dealer or automotive electrical supplier. Measure the exact length you want before you buy. They will probably crimp the terminals on for you, but check the diameter of the studs. Most batteries will be 8mm, but the inverter may be l0mm.

If you have to mount the inverter further away, use 70mm cable, or two 35mm cables in parallel for both positive and negative.

Unless a main input fuse is already fitted, you'll have to fit a 250A fuse in the supply line. It's also a good idea to have a separate battery master switch in line, so you can disconnect the unit completely. This must be capable of taking 250A continuous load. Check the size of its terminal studs - they will usually be l0mm.

The DC input terminals on some units were very close together, risking short circuit. If there are no plastic terminal covers, fit your own.

Your battery bank is a major consideration when fitting any but the smallest inverter ...If you take 200A out of a fully-charged 200Ah bank, the voltage at the battery terminals will drop from 12.6V to 11.0V at the inverter. If the bank is only half-charged, the voltage could be down to 10.5V, close to the low voltage tripping point of 10.0-10.5V.

If you're fitting a 21kW inverter, you should have a minimum of 400Ah batteries, preferably 600Ah. For a 1 kw unit, you will need 200Ah, preferably 300Ah.

All these figures assume the engine is not running, which is the usual situation when moored. If you start it up, you will get an input from the alternator, and the battery volts will rise, which will improve the situation, but you should not rely on this.

The condition of your batteries is also important. High continuous current drains will hammer the bank, and quickly find out any weak cells. Gel or AGM batteries will be better able to handle continuous heavy loads.

The 230V output from the inverter will be either one or more sockets on the front, or you may have to hard-wire a cable internally Again, only do this if you are sure of your proficiency. UK three-pin outlets are best fitted sideways or upside down so that large plugs or power-supplies dont foul the base.

Because the inverters have to be close to the batteries, they will usually be mounted in the engine space, or at least away from the galley area. But because most of them have a continuous residual current drain in standby-mode, you don't want to leave them permanently switched on. A remote control panel allows you to turn off the inverter when it's not needed.

Ideally you should fit a change-over switch in the output circuit to switch the incoming AC power between shore supply, generator, and inverter. It's important that you don't have two different power sources feeding into your ring main at the same time. Make sure you get the polarity right when connecting the DC or you could damage the unit

Any piece of electronic equipment will give a high short-term output, but will quickly cut out as it heats up. Best practice is to use the continuous rating to describe the unit. Having said that, the intermittent rating is important, as some pieces of AC equipment, particularly those with motors in them, have a start-up surge that needs a short burst of higher power.

Most power inverters drain a continuous current when switched on, even when you're not using them. This standby current will be at least 2A, sometimes more, which, over 24 hours, it could drain 50Ah or more from the batteries.

This is why a remote control is important. Some models have a powersave mode. This sends the unit to sleep while nothing is connected and wakes it up when it's needed. The drawback to this is that tiny currents, like the timer light on a microwave, will not trigger the unit, so the microwave won't start. Your mobile phone charger will also probably not activate the inverter, so you still need to turn it on manually.

boatpartsdatabase

http://www.boatpartsdatabase.com has lots of resources for the boating trade and public alike.

The web is a vast source of information. Boatpartsdatabase collects the leisure marine industry into one huge database of contacts.

The Difference Between a Low Cost Power Inverter and the More Expensive Models

Have you ever wondered why some inverters cost much more than others of the same power. I will briefly describe one of the main differences between a low cost power inverter and a high cost item.

Finding a power inverter to convert DC power to AC may seem like it should be a simple task, but when you start shopping for a power inverter for your personal use, you'll soon find that many choices will confront you. With prices ranging from less than $25 to well over a $1000, it can be difficult to know what features are important and how to choose a unit appropriate to your needs.

While wattage you need and how you will be connecting the unit to your power source are items to be taken into consideration, another item that you should take into account is the inverter's wave form output. There are two general types of power inverters: true-sine wave or modified-sine wave (square wave). True-sine wave inverters produce power that is either identical or sometimes slightly better to power from the public utility power grid system. The power wave when viewed through an oscilloscope is a smooth sine wave. Modified-sine wave and square wave inverters are the most common types of power inverters on the market. Modified-sine wave power inverters produce a power wave that is sufficient for most devices. The power wave is not exactly the same as electricity from the power grid. It has a wave form that appears as a choppy squared-off wave when viewed through an oscilloscope. What does that mean to the everyday user? Not much. Most household electrical devices will run perfectly fine on either type of wave form.

Most of our customers who are using a power inverter to run a laptop, a/c cell phone charger, fan, or camera find that a modified-sine wave power inverter that operates through the cigarette lighter socket the easiest to use.

We usually suggest choosing power inverters that are rated under 300 watts when using the 12-volt cigarette lighter socket found in most vehicles. We suggest this because after reaching 300 watts of draw on the inverter, the fuses in your car will begin to blow. There are several units available on the market powered between 100-200 watts that plug directly into the cigarette lighter of a vehicle. It has only one outlet, but since plugging it into a 12 volt socket is all that is required for operation, it can't be beat for ease of use. These little units usually supply around 150 watts of continuous operation and normally have a built in surge protector.

Square wave units or your low cost power inverters fall into the following three groups:

500w or less For household appliances, TVs (up to 19"), VCR, desktop computers, other mobile office equipment. Most of these connect via a 12-Volt plug.

501-999w For household appliances, large screen TVs, 5-amp power tools, and bread machines. Most such inverters are connected directly to the 12-volt battery and have three or more grounded outlets for powering several products at the same time.

1000-3900w For household appliances, larger power tools, microwave ovens, toasters, and hair dryers. All of theses inverters are designed for direct connection to the battery network and can generally supply 750- 2500 watts of continuous power.

The problem with wave form only comes into play when specialized pieces of equipment need to be powered. Here are a few devices which could have problems when they are connected to an inverter producing a modified-sine wave signal: oxygen concentrators, fax machines, laser printers, high voltage cordless tool chargers, equipment with variable speed motors, electric shavers, and garage door openers. For most all other applications you can go with the low cost power inverter.

In closing, it is really not necessary for the average user to go with the true sine-wave unit. The modified sine-wave found in most low cost power inverters will be sufficient take care of your applications.

For more information on power inverters please visit http://inverterssavegas.com

How Does A Power Inverter Work?

People always ask us "exactly how does a power inverter work?" The answer to this question often surprises our customers. Car power inverters work much more simply than mysteriously, and the learning curve required to understand them requires no more than a very basic knowledge of electricity. Essentially, there are two forms of electrical power in the Universe: Direct Current (DC) and Alternating Current (AC). Direct current flows continuously from the positive electrical pole to the negative electrical pole. Alternating current flows back and forth between the two poles. DC current occurs in Nature and batteries, while AC current is man-made and supplies power through the public utility grid that supports human industry and infrastructure. Car batteries presented a problem in the past when people realized they needed to operate traditionally AC-powered devices in their cars but could not do so because of incompatible current requirements. Manufacturers like Vector stepped up to solve this dilemma by working to design car power inverters that would safely and efficiently convert DC to AC. Their successful engineering has resulted in a wide range of compact, rectangular devices that connect to batteries and output the resulting alternating current safely through one or more standard electrical plugs.

Two factors determine how a power inverter works: wave output and wattage output. Wave output describes the physical appearance of electrical signals as they move across an oscilloscope. Square waves appear exactly as their name specifies: like squares on a grid. Pure sine waves, also called true sine waves, appear as visible waves on the screen. Sine wave car power inverters work better than square wave power inverters when uninterrupted power flow is a critical issue. In fact, true sine output is sometimes slightly superior to that of public utility power grids! Because of this, they are also the most expensive devices of their kind on the market. Recent advances in technology have accommodated users on a budget with a hybrid design generally referred to as either a modified square or modified sine wave power inverter. The technical differences that determine how a true sine car power inverter works and how a modified sine power inverter works are too minor to produce any noticeable effects with standard electronics. Only the most high-end equipment requires true sine output, and the cost of these devices may justify the additional investment in pure sine technology to deliver maximum quality and reliable performance.

Another new development that allows car power inverters to work with even more reliability than ever before is the sophisticated Soft Start Technology, branded "SST" by manufacturers such as Vector. SST is the next step in the evolution of how power inverters work. The very first power inverters for cars would only work intermittently during cold engine starts. Because they could not pull enough power from the battery, they would shut down from current underload and require a manual restart. SST resolves this issue by gradually increasing voltage ramp up during engine startup. If the output dips for any reason, SST makes instant adjustments to compensate and will prevent most shutdowns. If in the rare event a shutdown does occur, the newer car power inverters work automatically to restart themselves without distracting the driver from the road.

Red Hill Supply delivers only the best and most reliable power inverters that will work in virtually any situation requiring DC-AC conversion. Learn more about how power inverters work in our Resources section, and browse our online catalogue to obtain the most high end.

Jason has been in the construction equipment and industrial sales business for over 10 years. He owns and operates Red Hill Supply to better serve the automotive and industrial industries. - Automotive Tools

How a Power Inverter Can Save You Money Over a Gasoline Generator

It is based on using an inverter in home emergency purposes rather than a completely built unit that would power an entire house. These units often require large battery banks with an external source of power such as sun or wind generators to keep the batteries charged. Nor will it cover large gasoline, diesel, or propane generators that are connected to the fuse box of a house and power an entire house.

What it will be covering are small home generators that usually have a 3-5 gallon gas tank and a 2- 6 HP engine. These are run outside the house and power certain appliances inside the house via an electrical cord attached to the generator. The electrical power inverter we will be discussing will be powered by a single car battery which will require recharging every one to two hours by running the engine of the car.

Studies have shown that a V-6 automobile engine uses approximately 0.5 gallons of gas for every 90 minutes it is run. What this translates out to is that if you were to run a 750 watt inverter, you would have to recharge a 120amp battery every 2 hours by idling the car for 10 minutes. This means that you could get 36 hours of use from a 750 watt inverter on one gallon of gasoline. This equals a $3.00 fuel price every 24 hours if gasoline is priced at $4 a gallon.

A 4400 watt gasoline generator uses about 3.2 gallons of gasoline for every 8 hours of service. This comes out to 9.6 gallons of gas for a 24 hour period or around $38 for 24 hours of use.

If you are using a smaller generator such as a 1000 watt model, which in most cases is more practical, you would be using 1.2 gallons every 5-8 hours depending on the load. This comes out to $5 every 8 hours ,or $15 for every 24 hour period.

Now for the power inverter numbers. If you were using a 750 watt power inverter, which would be enough to power a laptop, small tv, dvd player, satellite dish box, and a lamp it would use 0.2 gallons for every 8 hours or 0.6 gallons for every 24 hours. for a cost of $2.40.

In summary the cost of running a 4400 watt generator for 24 hours is $38 and a 1000 watt generator for 24 hours is $15 and the cost of the inverter for 24 hours is $2.40

I feel many people do not use power inverters in emergencies just because they aren't familiar with them. They're easier to hook up then a generator. You just have to clip it on to your battery, plus the savings is substantial if you have a power outage for an extended period of time. For more information on this subject and the products come visit http://www.inverterssavegas.com.

Introduction to Inverters

In the context of renewable energy, an inverter is a device that will convert DC battery voltage into mains type AC power.

Most medium to large scale solar power systems are designed to power everything from mains type AC voltages "inverted" from the DC battery bank. The advantage this gives us is that we can purchase conventional appliances from an electrical retailer. An energy efficient light globe can be somewhat expensive in a 12 Volt DC version and having a 24 or 48 volt lighting system makes finding a suitable light bulb even more difficult.

Inverter ratings

The three ratings that you should look at when buying an inverter are:

1. Continuous Rating: This is the amount of power you could expect to use continuously without the inverter overheating and shutting down.

2. Half Hour Rating: This is handy as the continuous rating may be too low to run a high energy consumption power tool or appliance, however if the appliance was only to be used occasionally then the half hour rating may well suffice.

3. Surge Rating: A high surge is required to start some appliances and once running they may need considerably less power to keep functioning. The inverter must be able to hold its surge rating for at least 5 seconds. TVs and refrigerators are examples of items that require only relatively low power once running, but require a high surge to start.

Types of inverters

There are basically two types of inverters: modified sine wave (aka modified square wave) and true sine wave. The differences between these two types of inverters are subtle but significant in the way they operate.

Modified sine wave inverters

A modified sine wave inverter can adequately power some household appliances and power tools. It is cheaper, but may present certain compromises with some loads such as computers, microwave ovens, laser printers, clocks and cordless tool chargers. Virtually all low cost inverters are "modified sine wave". A modified sine wave is easier and cheaper to produce than a sine wave inverter.

These low cost inverters are generally available from electrical stores, hardware stores, automotive store and electronic suppliers. They usually lack many features such as auto-start or any type of tweaking ability. The devices are usually only about 70% efficient, so expect some significant power losses if you are using a modified sine wave inverter in your system.

True Sine wave inverters

A true sine wave inverter is designed to replicate and even improve the quality of electricity supplied by utility companies. To operate higher-end electronic equipment, a true sine wave inverter is recommended. Efficiency has reached up to about 94% and the electricity from these devices is of a higher quality than grid power almost anywhere in the world.

A high quality inverter will include:

* An auto-start system. An auto start allows an inverter to switch to a low power consumption standby state when nothing is connected and turned on. This will save you a lot of manual switching and/or wasted power

* Tweaking ability. An ability to adjust parameters such as auto-start and battery depth of discharge is also helpful.

* High quality heavy-duty power transformer. A heavy inverter usually means a high quality heavy-duty power transformer.

If you are running sensitive electronic equipment, don't take the chance - get a true sine wave inverter. The extra cost will make up for itself in energy efficiency.

Michael Bloch is a consultant for Energy Matters - Wind and Solar Power Australia - a green energy equipment company offering a wide range of discounted solar panels, deep cycle batteries, power inverters and associated accessories for residential, businesses and schools. The Energy Matters site contains a wide range of resources; including a solar power system builder tool, renewable energy rebates information and free advice on off grid and grid connect solar and wind power systems

Multi-Port Power Inverter

Check out this cool tech stuff. It's a Multi-Port Power Inverter which you can plug into your car's cigarette lighter to have 2 USB ports and an AC socket at your fingertips. From this Multi-Port Power Inverter , you can easily gain a 110-volt AC outlet on the road and use it to run laptop, video camera, or portable CD/DVD, shave or to recharge batteries while you drive.

Cheap Power Inverters

Quality is the hardest thing to evaluate from the description of a power inverter. You can go by status or by price (i.e. you generally get what you pay for). Cheap power inverters can be good value for money, but be prepared to purchase another one at short period.

Power Inverters convert DC power stored in batteries into AC power to run conventional electronic equipments. A power inverter allows you to run computers, entertainment systems, power tools and kitchen appliances.

Power inverters differ in price, power rating, efficiency, waveform and reliability. They produce three types of waveforms, square wave, modified sine or square wave, and true sine wave. The simplest and cheapest is a square wave inverter, but today it is uncommon. Many devices will not work on a square wave signal. True sine wave inverters work well, but are expensive. It is important to remember that the cheap power inverters might not be of good quality.

Cheap inverters often produce a square wave signal that has the same frequency of a modified square wave inverter, but sharp edges in place of smooth curves. They cause noises in many appliances, but they work quite good most of the time. Transformer operated appliances actually don't like this type of signal. There is really a risk of damaging the power supply running it from a cheap power inverter.

Cheap inverters are fine for light bulbs, but appliances like variable speed motors (e.g., electric drills) and sensitive electronics (e.g., computer power supplies) often get damaged. Lots of cheap inverters are available in the market these days. One way to find such inverters is to read the advertisements and special deals posted by each of the major companies. Then simply compare the prices from company to company and select one. The Internet is also a place where you can do all your cheap inverter research and purchasing.

Power Inverters provides detailed information on Power Inverters, DC To AC Power Inverters, Emergency Power Inverters, Car Power Inverter and more. Power Inverters is affiliated with How to Replace a Circuit Breaker.

The Growing Uses of AC Power Inverters

I have learned that there are many other uses for DC to AC power inverters. They are very popular with boaters, people who have recreational vehicles, campers, long distance travelers and those who use alternative ways of making electricity.

Those who enjoying boating, camping and traveling in recreational vehicles connect them to their vehicle's battery and use the power inverter for back up electricity. The power inverters change the DC current of their battery into AC current that can power the lights, a television, radio and even appliances. They can enjoy the modern conveniences of home in places where there is no electricity available. They can enjoy being on the water or in a remote location, but it doesn't keep them from staying in touch with the world around them and using the electrical things they want and need.

People traveling long distances can use smaller power inverters inside their vehicles. These are connected to the cigarette lighter or another charging receptacle and used to recharge batteries for MP3 players, video games, cell phones, cameras or any electronics that require 120 watts or less.

There are also people that make their own electricity. They store the electricity in a battery and then need to convert it to AC electricity by using a power inverter. I was contacted by a person who peddles a bicycle to make his own electricity. He has an inverter connected to the battery he is charging and watches a television, that is plugged into the inverter, while he is peddling and charging the battery. Also, people who use solar panels of any size can make electricity and this does save money, but this electricity still has to be converted to be usable.

The one thing I did notice is that not too many people were aware of using the power inverters for a power outage in the home. They probably didn't think about getting a spare 12 volt battery to keep in the house for emergencies. Most people connect their power inverters to a vehicle's battery and probably thought it too difficult to run the power into the house. That is why having a spare battery is the perfect solution. You can keep the power inverter and battery together in one place and when an outage occurs, you are ready for it.

Because so many things require electricity or batteries to operate them, the popularity and uses for power inverters should continue to increase and it wouldn't surprise me if soon, everyone will own at least one power inverter.

Sandra is the owner of http://www.energyigloo.com - a new store with everything you need for free electricity. This information comes from personal experience and research.

See Sandra's products at http://www.energyigloo.com and join her free newsletter for new products and sales news.

What are Power Inverters?

The storage batteries used in alternating power systems store DC (direct current) power. But, most modern electronic appliances depend on AC (alternating current) power. A power inverter can provide the comforts and conveniences of modern living. It is an electronic piece of equipment that converts DC power into conventional AC power.

During blackouts, a power inverter can be used for emergency power. It is used to run all sorts of household equipments, including kitchen appliances, power tools, TVs, computers, and more.

Power inverters are normally small, rectangular shaped units. There are normally one or two outlets available for standard cords. Inverters normally draw their power from 12V, 24 V batteries, or several batteries wired in parallel. The batteries are discharged as the unit draws the power out of it. Automobile motors, solar panels, gas generators, and other standard sources are used for battery charging.

Power inverters are available in several models that differ in watts. The required amount of inverter wattage depends on the total draw of the devices, plus at least 50% more to account for peaks or spikes in the power draw. For example if your computer draws 100 watts and your home theater another 100 watts, a minimum 300 watt inverter is suggested.

A typical power inverter produces square wave, modified square or sine wave, and pure sine wave (true sine wave). The waves denote three dissimilar qualities of power output and three different price ranges. Owing to uneven power delivery, square inverters, the initial types of inverters, are almost outdated. Modified inverters, less expensive and probably the most common, produce consistent and efficient power. True sine wave inverters are highly expensive and they also deliver the most consistent wave output.

Always use highly rated power inverters for the devices you are running. Avoid adapters that would permit more outlets than the unit is designed to accommodate. Since improper use of a unit may lead to burning, make sure that you read and follow all safety measures listed in the user?s manual.

Power Inverters provides detailed information on Power Inverters, DC To AC Power Inverters, Emergency Power Inverters, Car Power Inverter and more. Power Inverters is affiliated with How to Replace a Circuit Breaker.

Honda Invertor Generators

Nothing has been quite so exciting in the generator manufacturing business as the new Honda inverter generators. Honda inverter generators give you all of the power that you need in a generator, with maximum fuel efficiency, light weight, and surprisingly quiet performance. Add to this Honda’s reputation for excellent quality, and these new generators are great news.

Regular gas generators are fine for running certain electrical appliances, such as lights and televisions. However, for more sensitive equipment such as computers, they are usually not sufficient. Computers, printers, and other sensitive electrical equipment need a constant, even electrical signal in order to work properly. The electricity generated from regular gas generators can tend to fluctuate; not a problem for lights, televisions, or coffee pots, but a possible disaster for more sensitive equipment.

The Honda inverter generator is the solution to this problem. Using inverter technology, Honda has created a generator that contains a microprocessor that regulates the flow of electricity from the generator, mimicking the flow that would come from a regular household outlet. This regulated flow of electricity makes it perfectly safe for anyone to run a computer or printer using a Honda inverter generator, without worrying about fluctuations causing a crash in the equipment.

Another benefit of using inverter technology is that Honda inverter generators need only be about half the size and weight of conventional generators, though they have every bit as much power. The alternator is built right into the Honda inverter generator, making it much more compact and light, and giving it exceptional portability. The fuel efficiency of the Honda inverter generator is unsurpassed; one small thirty-pound model can run up to eight hours on a single tank of gas, and a larger forty-six pound model can run up to fifteen hours on one single tank. As far as noise level, the Honda inverter generators run so softly that most people would not even notice that they were in use.

Though the Honda inverter generator is extremely efficient, you still want to choose the right model for your needs. Even though Honda inverter generators are smaller and lighter than their conventional counterparts, there are still different sizes from which to choose. The standard rule does apply with Honda inverter generators: the larger the model, the more work it will do. When shopping for a Honda inverter generator, keep in mind the tasks that you will need it to perform, and buy accordingly. The salespeople and technicians at Honda should be able to help you find the Honda inverter generator that suits your purposes.

Buy a Honda generator or just check out the Honda eu2000i generator today.