FREQUENTLY ASKED QUESTIONS AND ANSWERS
Can I operate a microwave with a power inverter?
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 is usually 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.
What battery do I need to run my inverter ?
Batteries are the heart of an inverter-powered electrical system, storing power for use on demand. The
most basic way to draw electrical power from a battery is direct current (DC) at the nominal voltage of
the battery. Your car radio, for example, uses 12 volts DC (12Vdc), the same voltage as your car battery.
Many off-grid electrical systems (those not powered by electricity from a utility company) use 12-volt
DC power to run simple loads such as lights. (Any consumption of electrical power is called a load.) Such
systems are commonly referred to as low-voltage DC systems. Powered by a 12-volt DC system, you can
enjoy the benefits of electric lights, entertainment systems, laptop computers, and other devices that can
be operated off a car battery. However, you can't run power tools, kitchen appliances, or office machines,
without the help of some device that generates "household" electricity.
An ideal way to run these devices is from a DC power sources such as vehicle batteries using an inverter.
An inverter is a device that converts battery power (DC) into alternating current (AC) of a higher voltage.
DC-to-AC inverters have been around for a long time. Energy loss in this conversion process at first was
very high: the average efficiency of early inverters hovered around 60%. In other words, you would have
to draw 100 watts of battery power to run a 60-watt bulb.
A new way to build inverters was introduced in the early 1980s. These fully solid state inverters boosted
efficiency to 90%.
The key to SkyTronic reliability is the elegance of our design. We use a sophisticated Field Effect Transistor
(FET) circuitry to convert the batteries' DC voltage (usually 12 or 24 Vdc) into AC. The resulting low
voltage AC is then transformed into a higher voltage, usually 120 or 220 Vac. All of the power shaping -
conversion to AC - and waveform shaping takes place on the low voltage side of the transformer.
One note of caution: Batteries only have a limited power storage capacity. To avoid draining a battery
and thus avoid the possibility of damaging it, you need to calculate and monitor the electrical
consumption or your device.
If you are using a 150W or 300W SkyTronic Inverter, a standard 12v vehicle (50/75A) battery is ideal, as
the inverter only draws a small amount of power. It comes with a vehicle cigarette lighter connection as
standard, so you can use it in your car while you're on the move, or you can attach it directly to the
battery, all the necessary leads are included.
For larger SkyTronic Inverters, we recommend a deep cycle lead/acid battery as the need for recharging
is more important and prolongs the battery's life. This type of battery is commonly found in caravans,
motor homes, Recreational Vehicles and boats.
How much power does the Inverter take from the battery ?
This obviously depends on the load connected to the inverter and the following is a basic calculation only.
Divide the load of the device connected to the SkyTronic Inverter by 10 (12V) or by 20 (24V).
For example: For a 400W appliance connected to a 12V inverter/battery, the power used would be 400
divided by 10 = 40A.
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