Unit that measures frequency, i.e. the number of times per second that an
alternating current (AC) changes direction. In Europe this is 50 Hz, and in the
USA 60 Hz.
High-frequency (HF) switch technology
This technology allows incoming alternating current to be rectified into direct current over
a diode bridge. The resulting DC voltage is chopped into parts with a high frequency by
means of an electronic switch that is turned on and off quickly. This creates a simulated
alternating current with a high frequency, 35 kHz (35,000 Hertz) for instance. This AC can
be converted to a higher or lower voltage via a very small transformer. The higher the
frequency, the smaller the transformer can be. Mastervolt uses HF switch technology in
all its equipment, offering major benefits in terms of compactness, weight and efficiency.
Another advantage is that you say goodbye to the irritating hum of a transformer.
Highly explosive gas mixture of hydrogen and oxygen formed during the charging of
flooded batteries with an unsuitable charger. Extra ventilation prevents concentrations
from becoming too high.
The International Electrotechnical Commission (IEC) is headquartered in
Geneva, Switzerland, and develops general standards for the safety of
electrical components and equipment. Although it proposes standards, the IEC is not
responsible for their enforcement, which is usually carried out by independent test
The power intake of the battery charger
can be regulated via the system panel,
up to the point where the maximum
for the AC fuse has been reached. The
advantage of this system is that heavy-
duty consumers such as hair dryers are
powered via the inverter and cannot
therefore overload the AC fuse. When
such consumers are connected to the
inverter, consumption from the batteries
is usually higher than the battery charger
can supply. This is rarely a problem
as major consumers are usually used
for a short time and the consumption
measured in Ah tends to be low. After
the consumer has been switched off the
battery charger will recharge the battery
The number of times per second that
alternating current changes direction,
expressed in hertz (Hz).
A situation where two circuits
are electrically connected
without their grounding or earth coming
in contact. Galvanic isolation is best
achieved by means of a transformer.
The voltage level at which a battery
starts producing gas. At at an ambient
temperature of 20 ºC, the gas voltage is
2.4 V per cell or 14.4 V for a 12 V battery
and 28.8 V for a 24 V one.
Batteries where the electrolyte (mix of
water and sulphuric acid) is absorbed in
a gel. As they are entirely maintenance-
free and rarely produce gas, Gel batteries
can be fitted anywhere. Extra gas
extraction is not necessary. Gel batteries
are highly suitable for lighting and as
onboard service batteries, and can be
charged very quickly thanks to their
special construction. With normal use
the lifespan of a 12-volt Gel battery is
between six and seven years. For the 2
volt traction Gel version, 15 years is not
uncommon. A Gel battery is very suitable
for (deep) cycle usage.