ALARMS FOR CHARGEMASTER BATTERY CHARGERS
Frequently asked questions
How much battery capacity
do I need with an inverter?
As a rule of thumb, the minimum
required battery capacity for a 12-volt
system is around 20 % of the inverter
capacity. For 24-volt inverters, it is
10 %. The battery capacity for a 12-volt
Mass Sine 12/1200, for instance, is 240
Ah, while a 24-volt Mass Sine 24/1500
inverter would require at least 150 Ah.
The indicated battery capacity is only for
the inverter. The capacity required for
other loads should be added to it.
How much power does an
Mastervolt sine wave inverters have
an output efficiency of more than 92 %,
which is the maximum that can be
achieved with modern technology. If you
connect an 850 W coffee maker to a Mass
sine wave inverter, consumption will be
850 W divided by the onboard voltage
of 12 volt, approx. 70 A. Of course, a
coffee maker will only be in use for a
short period of time, so the consumption
measured in Ah will be relatively modest
(76 x 5 min. = 6.5 Ah). As a rule of thumb
you should divide the connected capacity
by 10 for 12 volt and by 20 for 24 volt.
This also includes all the power losses in
the cables, fuses and the inverter.
Is there a stand-by switch
on the inverter?
Definitely! Although the no-load
consumption is extremely low, most
Mastervolt inverters and Combis are
even equipped with two energy saving
solutions. Activating the Economy mode
reduces battery consumption by an
extra 10 %. This function requires an
adjustment to the dipswitch/jumper
settings, which can possibly be realised
via the free downloadable software. The
economy mode ensures that the output
voltage drops slightly to 208 V, which also
reduces the power consumption from the
battery. Low-load devices like microwaves
and DVD clocks function as normal at
this lower voltage.With some inverter
models it is even possible to activate
a stand-by mode. In this mode the
inverter sets a tiny pulse on the 230-volt
installation, checking for any connected
appliances. As soon as the pulse detects
consumption, voltage returns to normal
strength to power the connected
equipment. The economy mode ensures
that the power consumption of the
inverter stays at virtually zero.
Can I power a computer
with an inverter?
Yes, you can. All Mastervolt sine wave
inverters can easily and safely supply a
computer without the slightest problem
or risk. In fact, the output voltage from
an inverter is often better than that from
the electricity grid or shore power. This is
why Mastervolt inverters, combined with
a battery charger and a battery set, are
often used as a back-up system in places
where the grid connection is unreliable.
Laptops can also be powered by a
Can a microwave be powered
with an inverter?
Any microwave model can be connected
to a Mastervolt inverter. Bear in mind
that an 800-watt microwave consumes
about 1200 to 1300 watt from the 230-
volt system, and that the capacity of the
inverter and battery must be able to
Apart from that, the total consumption
of the microwave-inverter combination is
moderate: Using the microwave for five
minutes will use around 12 Ah on a 12-
volt system and 6 Ah on a 24-volt system.
Are there any appliances that
cannot be powered by an
You can connect almost any appliance
to an inverter, with a few practical
exceptions. In practice you must be
careful with equipment that consumes
a lot of power, such as electrical heaters
or air conditioning. While the inverter
itself has no problems with these loads,
the battery capacity is often too limited
for long-term usage of these loads.
Appliances that are only used for a
limited time period, such as washing
machines, driers or a small hotplate,
should be fine as long as the battery
has sufficient capacity. In these cases it
is advisable to use a power source such
as an alternator, which also powers the
battery. Keep in mind that heavy users
such as engines, pumps, air conditioning
and fridges have a starting current that
is between 5 to 12 times higher than the
nominal absorbed capacity. The inverter
has to be able to supply accordingly.
Mastervolt inverters are developed to
provide high peak currents.