Product specifications

High frequency fly back
power converter
This converter is the heart of all Sunmas-
ter QS inverters. It is used as a basic buil-
ding block to build the whole range: two of
these converters are in the QS1200 and
QS2000, four in the QS3200 and six in the
QS5000. The converter is built from effi-
cient high frequent power Mosfets, high
voltage capacitors and two high frequent
Class II safety transformers. The converter
converts the solar DC voltage into a pure
sine wave with a suitable peak voltage and
frequency, matching the grid characteris-
tics. The high frequent switching (25,000
times per second) enables the clear build
up of a well defined sine, resulting in an
extremely low harmonic distortion at the
grid side (THD<<3% in compliance with
IEEEp929).
MASTERVOLT SOLAR SUNMASTER QS SERIES
TECHNOLOGY
Advanced technology
SUNMASTER QS SERIES
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With each Sunmaster QS you buy, you buy an
inverter, designed, produced and tested to last for
an extended periode of time. High frequent Mosfet
technology combined with high frequent Class II
safety transformers, provide safe, efficient and
lasting power conversion in a compact, low
weight enclosure. Typical Mastervolt novelties,
such as QNS redundant grid monitoring, multiple
Solar MPPTracker inputs, solar earth fault detec-
tion and the transparent extensive monitoring
options, including wireless communication, give
you the tools to provide a solution to every wish
you might have.
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High frequent Class II
safety transformers
These transformers not only convert the
full power but also provide the galvanic
separation between grid and solar side of
the inverter. Galvanic separation means
that the grid and solar side are not electri-
cally connected, providing a very high level
of safety: in case of failure, there is no pos-
sible way, in which the grid voltage might
be passed onto the solar side and vice versa.
The power is transported from solar to
grid side using electro-magnetive coupling
inside the transformers, which is only pre-
sent when the QS operates properly. High
frequent switching technology makes it
possible to use the transformers in a very
efficient way. The same power is transpor-
ted through a much smaller high frequent
transformer (weight & size ten times less)
than would be possible using conventional
low frequent technology. This explains the
fact that the QS products are so very com-
pact and low weight. The additional ad-
vantage is that the whole unit is assembled
on one single board. This makes assembly
more easy (less faults) and makes complete
in circuit and functional testing possible.
Temperature controlled
derating
The QS inverters are able to convert more
power than their nominal specified power
for certain periods of time. In principal
this power is only limited by the amount of
heat production in the inverter. Excess heat
is first removed from the cabinet by forced
cooling by the low energy, temperature
controlled fan. When this is not enough,
the power from the array is reduced by a
slight increase of the DC voltage, moving
the DC voltage away from the MPPT
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