Power Inverter FAQ

Please read the Frequently Asked Questions below to help answer any questions you may have about our 8Zed Power Inverters.

What is a Power Inverter?

8Zed Power Inverters are devices designed for powering household appliances from a car, or similar battery. They convert 12V DC battery power to 240V AC mains power and are an ideal source of portable mains power. Being compact and portable, power inverters can be used in cars, caravans, boats, 4WDs and trucks. Using a power inverter for household appliances is a much cheaper option than purchasing specialized 12V appliances for those times when mains power is not available. Compared to Generators, Power Inverters are a greener and cheaper long term option.

What are the different types of inverters?

There are two different types of power inverters: modified sine wave and true sine wave inverters.
The difference between the two types is how close the output power replicates standard AC mains power.

To gain a clearer understanding of the difference in output between mains power, modified sine wave and true sine wave inverters, check out the diagrams below.

A true (or pure) sine wave inverter is far more complex than a modified sine wave inverter and as a result is more expensive item to purchase. Modified sine wave power inverters are more common due to the fact that most electric appliances do not require a true sine wave power source. True sine wave inverters are reserved for use on medical equipment and other sensitive electrical applications.

8Zed Power Inverters are available across a range of power output levels to power a range of appliances. Small power inverters, such as the 120 Watt & 300 Watt 8Zed Power Inverters, are designed for powering one small low power electrical appliance whereas larger units are suitable for powering multiple small appliances at the same time or just one larger appliance.

Power inverters are not an efficient way to run appliances that require very high power requirements eg: electric heaters, stoves, kettles and air conditioners. This is due to their high current draw and therefore rapid battery depletion.

What is a suitable power source to operate an inverter?

To operate an inverter and supply power to an appliance, a suitable 12V DC power supply is required. This can be a vehicle, boat or caravan battery, portable power pack or an independent 12V lead acid battery. For most applications, a deep cycle battery is recommended for best performance.

How do I connect to a power source?

CAUTION: Before making any connections ensure inverter is switched off and has no AC appliances plugged into the AC output sockets.

Connect the ring terminal on the negative lead (Black) to the negative (Black) DC terminal on the back of the inverter.
Connect the battery clip (Black) or ring terminal on the other end of the lead to the negative DC supply or (-) battery terminal.
Connect the ring terminal on the positive lead (Red) to the positive (Red) DC terminal on the back of the inverter.
Connect the battery clip (Red) or ring terminal on the other end of the lead to the positive DC supply or (+) battery terminal.

Why is it important to ensure the battery leads are not connected back to front?

The 8Zed inverter uses highly reliable electronics to convert DC battery power to AC mains power. If you accidentally connect the inverter to the battery incorrectly a large current will be drawn by the inverter which will blow the protection fuses, as this occurs some of the high current could damage the sensitive electronic components. Because of this risk it is important to always double-check the battery polarity before making any connections.

Do power inverters store power?

Power Inverters cannot store power, they just act as a ‘converter’ to change the power from a 12VDC power source to 240V AC. This enables you to use normal household appliances and tools from a battery or your vehicle.

How do I determine a suitable load for appliances?

The 120W, 300W and 600W 8Zed Power Inverters are fitted with 1 approved AS/NZS power socket. 1200W to 3000W 8Zed Power Inverters have 2 approved AS/NZS Australian socket outlets where either or both sockets can be used, as long as the combined load (watts required) does not exceed the inverters continuous power rating (please refer to the Inverter Selection Guide for more information).

Every appliance has a rating plate which shows users the amount of power (watts) required to run the appliance or the current (amps) drawn under normal use.

To work out which 8Zed power inverter you need to run your appliances, , please use our Power Inverter Selection Table for an approximate guide. Just tick the boxes for the appliances you want to use, and the table will calculate the right power inverter for your needs.

NOTE: Some appliances that use an electric motor or transformer may draw 2 to 6 times their rating when first turned on, known as inductive loads. These appliances are the most difficult for inverters to run.

If using these appliances with a power inverter, it can often be a matter of trial and error to see what size inverter they will require in order to run, but if you are in doubt always err on the side of a larger inverter.

How do I connect an appliance & run the inverter?

Connect the appliance AC plug to the inverter AC outlet socket.
Switch the inverter ON, the green power light will illuminate to indicate operation.
Turn the appliance ON, if the appliance is fitted with an On/Off switch always switch the inverter on before switching the appliance on and always turn the appliance off before switching the inverter off.
When not in use, turn the inverter off.

What is the right environment and appropriate way to set up the placement of my inverter?

In order for your inverter to operate properly, it should be placed on a flat surface e.g. on the floor or seat of a car. The inverter also should only be used in locations that are:

DRY – Keep the 8Zed inverter away from water
COOL – Ideal ambient air temperature should be between 10 degrees and 33 degrees Celsius (50 to 90 degrees Fahrenheit) The inverter should not be placed near a heating vent or any device that produces heat above room temperature. If avoidable, do not place the inverter in direct sunlight.
VENTILATED – Please allow two inches of clearance around the 8Zed inverter for air flow. Do not place anything on or over the inverter during operation.
SAFTEY – Do not use the inverter near flammable materials or in any location which may accumulate fumes or gases, such as the battery compartment of your car, truck, RV or boat. These inverters are not suitable for use while travelling using battery clamps because the length of the wire cables and battery clamps are not designed for this operation. If you wish to operate the 8Zed inverter while moving, it must be permanently mounted and wired.

How do I check or change the fuses?

The 300W and 600W 8Zed power inverters are fitted with one external fuse holder. If the unit is not functioning, disconnect the inverter from the DC power source and AC appliances. Remove the black fuse caps and the fuses to check if they have blown. The 120W, 1200W, 1800W, 2400W and the 3000W all have their fuses contained within the actual unit. If they blow, only a qualified electrical technician should open up the inverter, inspect and replace fuses if needed. You can replace the blown fuses with the spares provided or you can use a standard automotive blade fuse of the correct rating.

THE DC SUPPLY MUST BE DISCONNECTED BEFORE ANY REPAIR WORK IS UNDERTAKEN, THEN TURN THE ON/OFF SWITCH OF THE INVERTER “ON” TO DISCHARGE THE CAPACITORS.

How long will a vehicle battery last while powering an 8Zed Inverter?

The typical vehicle battery has a minimum operating time of 1 to 2 hours, depending on the current needed for the appliance in use and the size of the battery. We advise that the operator start the vehicle every hour to recharge the vehicle's battery system. This will prevent unexpected shut downs of equipment and will ensure that there is always sufficient battery capacity to start the vehicles engine.

My 8Zed Power Inverter will not run my appliance, even though the listed power requirement of the appliance is less than the inverter size.

Electrical appliances can be separated into three load types by the way they draw energy (current) from their power supply. The 3 load types are “Resistive”, “Inductive” and “Capacitive” appliances. Some appliances may draw all three types of power, in which case all should be considered.

Resistive Loads – for example a standard incandescent lights (wire filament), always draws a constant power (watts) from the power supply, that is a 100 Watt light will draw approximately 100 Watts from the power supply at all times. A Resistive load appliance is the easiest.
Inductive Loads – for example a fridge (electric motor), requires a large surge of power (surge current) to start and then typically draws consistent power once running. Inductive load appliances contain coils of wire such as motors, transformers, ballasts and solenoids. When the power is first turned on these coils of wire draw a large surge current which allows for the formation of the magnetic field or flux required for these appliances to work. The magnetic flux is in effect, stored energy. Most common inductive appliances are: fridges, air compressors, transformers, pumps, power tools & fluorescent lights. These types of appliances can draw between 2 and 6 times their normal running power at start up. For example, to start a 200 Watt fridge you may need a 600 to 1200 Watt 8Zed inverter.
Capacitive Loads – for example TVs, may require a large surge of current to start, especially if they have not been turned on for a while. This is often due to large capacitors in the power supply that must be quickly charged when the appliance is turned on. If the appliance is not used for several days these capacitors slowly lose their charge. Resetting the inverter a couple of times may overcome this problem and allow you to run these appliances.
Some appliances such as large refrigerators, air conditioners or other pump driven appliances, have extremely high demand for start-up current due to an inductive motor which must start under load. Appliances of this type are not recommended for use with an inverter. They should be powered by an engine driven generator.

Why do some power tools not function correctly?

Some newer power tools use Pulse Width Modulator (PWM) variable speed controllers to vary the tool's speed as the trigger is squeezed. These power tools switch the power on and off very quickly in a similar way to the functioning of the inverter. Because of this, some may not function properly with the inverter's modified sine wave output.

Can I connect my inverter directly to a solar regulator or controller?

It is possible to connect an inverter directly to a regulator/controller as long as the total amps being consumed by the inverter and anything plugged into it doesn’t go over the max amp rating of the controller. For example if you have a 12V controller rated at 12amps, and you connect a 300W Inverter which consumes 0.5Amps when turned on, you would be left with 11.5A to run your appliances (roughly 135Watts). If however you tried to use more than the power available from the regulator, you could cause damage to your inverter as well as your regulator/controller. As it can be hard to monitor exactly what power you are using, it is highly recommended to connect your inverter directly to your battery (or battery bank).

Can I connect lights with dimmers to the inverter?

Older style light dimmers may function correctly, however most modern light dimming circuitry is designed to work with household true sine wave AC power. These may not work properly with modified sine wave inverters, and therefore a Pure Sine Wave Inverter would be required.

Can I run fluorescent lighting from my inverter?

Most portable fluorescent lamps should operate fine on a power inverter. Please note they may be slow to start and may require up to 3 times the listed power (i.e. 20W Flurescent light = 60W Power required from an Inverter).
Fluorescent lights are an inductive and capacitive load and tend to draw twice as much power from the inverter.
Standard household fluorescent lights are not recommended because they contain Power Factor correction capacitors. Power Factor correction is normally used in buildings to help smooth out the inductive effects of fluorescent light ballasts. If they are used with a power inverter, the power factor correction is effected by the harmonic distortion in the modified waveform which can cause a high load for the inverter that can then overload the inverter. If you wish to use normal household fluorescent lights of a power inverter, it is recommended that you get a qualified electrician to remove the power factor correction capacitor.

Can I run laptop computers with my 8Zed power inverter?

Most laptop/notebook computer AC power adapters work perfectly well with the 8Zed modified sine wave power inverters. There are some laptops/notebooks which may be more sensitive so if your unit's power adaptor does not function or causes a humming noise, a pure sine wave inverter is recommended.

I have a 170W 240 volt gas fridge, is the 8Zed 300 watt power inverter suitable to run my fridge while I am travelling, using my car battery?

With Fridges, we normally recommend that it's a good idea to allow 2 to 6 times the required power. However this is due to the fact that normal fridges (with electric motors) require an Inductive Load and need a large rush of power (surge current) to start.

The 300W 8Zed Power Inverter would probably be enough to power the 170W Fridge, as long as there's no motor and to a lesser extent transformers, ballasts and solenoids.

Why won't my inverter work when I use a rechargeable Alkaline battery or an appliance with rechargeable AA or AAA batteries?

You may have trouble using a AA battery charger with any inverter due to the way the battery chargers draw energy. You will also find that a Pure Sine Wave Inverter is a better option for battery chargers due to the fact that there's much less ‘noise’ interference compared to a modified sine wave inverter. This ‘noise’ can often wear away at the sensitive components in cheap battery chargers. The rechargeable batteries, recharging transformer and/or the 8Zed Inverter may be damaged when trying to recharge devices of 10 volts or higher.

In most cases you can safely charge your laptop, mobile phone, cameras and cordless drills using a modified sine wave Inverter. For example, I can charge my Dell Laptop, my PDA mobile phone and my Black & Decker cordless drill via these power inverters.

However, it is always a good idea to double-check your appliance's manufacturer's guidelines first. If they can't be charged via a modified sine wave inverter, they will mention something similar to "Charge via Mains power only".

Why is my inverter making a whistling noise?

An alarm will sound when the voltage of the battery drops to 10.5 volts. This indicates that the battery requires recharging. You should cease operations at this time, since the 8Zed Inverter will shut down automatically when battery voltage drops to 10.0 volts.

If the low battery alarm still sounds when the battery is fully charged, try reducing the load on the inverter, and keep the voltage above 11.5 volts to maintain regulation. The alarm will sound when the inverter is overloaded, or if there is an excessive voltage drop between the battery and the inverter.

NOTE: The alarm may sound momentarily when the unit is being connected to, or disconnected from, the power source. This is normal and does not indicate any problem.

Why does my inverter turn its self off?

If the inverter makes a beeping sound and the “RED” fault light comes on, this indicates a problem, and the inverter will usually turn its self off for safety reasons. This is most commonly caused by an appliance that is drawing too much power thereby overloading the unit being used, low battery voltage or voltage drop which is due to insufficient sized cables or poor connections.

Why does the fan only operate sometimes on the 8Zed power inverters?

8Zed power inverters contain a temperature controlled automatic cooling fan that only operates when needed. This allows the inverter to run very quietly for most of the time. Smaller sized inverters such as the 200W, 300W and 600W 8Zed Modified Sine Wave Inverters have their fans running constantly to ensure they never overheat.

Can power inverters be used directly off a battery whilst the car is switched off?

You can run appliances through the Inverter off the Battery whilst the car is switched off. The time you can use it for will depend on the size of the Inverter and also the Appliance being used. As long as DC volts from the battery stay above 11Volts, it will run. It is recommended that the battery be charged at least once every hour to make sure there are no interruptions and to also make sure you can start the vehicle after use.

I would like to run an electric blanket and a small tv in my caravan, total watts about 400. What size inverter would you suggest and suit my needs?

Appliances that have coils that produce heat typically require 2 to 6 times the listed power. Therefore, if the blanket is rated at 100Watts continuous, you may require a 600W Inverter just for the blanket. With the TV, they typically require a large surge current if they haven't been switched on in a while. This is due to the large capacitors in the power supply that must be quickly charged when the appliance is first turned on.

Due to the factors above, the best Power Inverter I would suggest for your use is the 1200W 8Zed Power Inverter. Another benefit in purchasing this 1200W 8Zed Inverter is that it has 2x 240VAC sockets that would make things easier to connect the 2 different appliances.

What size inverter do I need to buy for a 600 watt microwave?

The power rating used with microwave ovens is the "cooking power" which refers to the power being "delivered" to the food being cooked. The actual operating power requirement rating is higher than the cooking power rating (for example, a microwave with "advertised" rating of 600 watts usually corresponds to almost 1100 watts of power consumption).
The actual power consumption in most cases is stated on the back of the microwave. If the operating power requirement cannot be found on the back of the microwave, check the owner's manual or contact the manufacturer.
Taking into account that for a microwave it is a good idea to add approximately a 20% buffer to the listed power, for a 600W Microwave I would suggest the 1200W 8Zed Power Inverter. This will make sure that the Inverter can supply the required power to the microwave consistently, even when the microwave is on High power.

Can I power a basic kettle to boil water and a radio with an inverter for my cigarette lighter?

To best work out what Inverter is required, you should find out the Wattage (power rating) of the appliances you wish to use. If you wish to use multiple items, add all the watts together then allow for 10-30% - i.e. 200W (radio) + 1000W (Microwave) = 1200W; 1200W x 20% = 1440Watts. Therefore the Inverter required would be the 1800W 8Zed Power Inverter.

Unfortunately it is not possible to power any sort of Kettle from a cigarette lighter plug. This is due to the fact that most cigarette lighter plugs can only handle up to 150Watts and most Kettles require around 2000Watts (minimum).

For more information on How to choose the right Inverter, you can view our Inverter Selection guide.

What are the measurements of the 8Zed 300 Watt inverter?

The 300W 8Zed Power Inverter is only: 16cm × 10cm × 5cm

Can I power my laptop and digital camera battery with a 8Zed 300 Watt inverter?

The 300W 8Zed Power Inverter should be perfect for powering your laptop and for charging your Camera Battery.

It would however be a good idea to double check the Power required on your Laptop (On the Power Pack and/or on the bottom of your laptop), and also your Camera charger (Bottom/back of charger). It is a good idea to allow at least 10% power buffer, so that's one other thing to keep in mind. (i.e. 200W Laptop + 10% = 220Watts)

I have a sprinter motor home it has air conditioner Heron 2.2 and a microwave, is there an inverter that will run these?

Microwaves are often around 1200W Max draw (Check the back of your microwave), in this case i would recommend an 1800W 8Zed Power Inverter.

This 1800W Power Inverter would make sure that your microwave can always be operated at max power.

Air conditioners' power usages are often listed in Horsepower (HP). If this is the case, you can use our power converter table. This will enable you to find out the total watts required of your 2 appliances.

Once you have these 2 power figures in Watts, just add them together and add 10%. This will tell you exactly what sized power inverter is required for your use.

i.e.
Microwave = 1200W
AirCon 2HP = 1492W
Total = 2692W
Sized Inverter required = 2692W × 1.1 = 2961.2Watts.(1.1 is the +10%)
Therefore a 3000W 8Zed Power Inverter would be the inverter that suits your application.

Can I run my 3-phase welder off your inverter?

Unfortunately a 3-phase welder cannot be used off an inverter because it only provides single-phase power.

Why does my power inverter only measure approximately 200V when using a standard multimeter?

True RMS Fluke multimeter will need to be used to accurately measure the volts of a Modified Sine Wave inverter. The rated voltage is an RMS (root mean square--they square the value to make sure it is always positive, then average it, then take the square root of the average to make up for having squared it in the first place) measurement.

Most multimeters are designed to give correct RMS readings when applied to true sine waves, but not when they are applied to other waveforms such as a Modified sine wave. When using a standard multimeter to measure the rated voltage from a modified sine wave inverter, your readings could be 5% to 20% lower in the true voltage.

Does the inverter drain power if it is turned off but still connected to the battery?

There is normally a small power drain of 0.5A – 1.3A experienced when the inverter is off.

If I'm only using a 600W appliance on a 1200W inverter, will the inverter use 600W or 1200W of power?

Your Power Inverter will still only use 600W. No matter what sized inverter you have the power draw will only be equal to what your appliance will draw.

What appliances are recommended to be used from a Pure Sine Wave Inverter?

The following appliances are likely to require a Pure Sine wave Inverter to function correctly; Medical Equipment, battery chargers, light dimmers, Variable Speed Motors, Laser printers, sensitive audio/visual equipment and digital clocks.
Some power tools may be a problem if they have a warning label stating that dangerous voltages are present at the battery terminals when charging.

What precautions should I take when installing an Inverter?

It is best to install an inverter in a cool and dry location. Inverters should not be installed in an engine compartment due to possible water/oil/acid/fume contamination, as well as excessive heat. It is also a good idea to run the battery cables in a secure dry place.

What sort of Inverter should I get to run my Laser Printer?

A Pure Sine Wave Inverter is the minimum that is required to be able to run a Laser Printer Successfully. Due to the heat rollers Laser printers use up a surprising amount of power (Even when they are on standby). Inkjet Printers on the other hand use much less power than a laser printer and can be used with a modified sine wave inverter.

Will an 1800W Inverter power my 1300W Heater?

The 1800W inverter could power the heater, however it is not recommended. This is due to Inverter efficiencies and the transfer of heat energy. A 2400W or 3000W Inverter would be our recommendation, however you will also require a large battery source due to the huge inrush of current required from a heater.

What does Inverter efficiency really mean?

The efficiency of an inverter refers to how well it converts DC Voltage into AC Voltage. Inverter efficiencies ranges from 80% up to 95%. The average efficiency is around 90%.
However, efficiency ratings can be decreased when using a resistive load such as an electric heater.
When running appliances with motors, the efficiency breaks into 2 parts; the efficiency of the inverter, and the efficiency of the waveform.
Waveform efficiency means that the motors and many other electronic appliances run better and use less power with a true or pure sine wave.
An appliance with an electric motor, like a pump or refrigerator will on average use 15-20% more power with a modified sine wave inverter compared to when it is run off a true or pure sine wave inverter.

When looking at the efficiency rating of an inverter you should also consider what you are going to run. i.e. An 85% efficient modified sine wave inverter is not going to run at 85% when powering a compressor motor. This is due to the fact that electric motors are less efficient and use about 20% more power off a modified sine wave inverter.

Powerinverterfaq | Performance Shop