coolcept³ fleX

StecaGrid 3213,StecaGrid 4013,StecaGrid 5013,StecaGrid 6013

coolcept flex S.jpg
coolcept flex G new 3ph.jpg
coolcept flex S.jpg
coolcept flex G new 3ph.jpg


inverter topology

The coolcept inverter topology was implemented in the single-phase StecaGrid inverters for the first time and achieved maximum efficiency thanks to the innovative circuit. The three-phase coolcept³-fleX inverters also enjoy the advantages of this circuit. The three-phase topology is fully reactive-current capable and thus also prepared for future requirements.

Always symmetrical

The advantage of three-phase feed-in is that the solar power produced is always distributed symmetrically over all three grid conductors and fed into the public grid. This is the case with these inverters over the entire power range. The symmetrical feed-in is entirely in the interest of the energy supply companies and also corresponds to the three-phase consumption in the household.

Highest efficiency with long service life

The very high efficiency results in a peak efficiency of 98.6%, which means that less power loss has to be generated and dissipated to the environment. These are your yield advantages.
Since a three-phase feed-in feeds energy into the grid on at least two phases at any time, intermediate energy storage in the device - as is the case with single-phase feed-in - is not necessary. Thus the coolcept³-fleX inverters completely dispense with the electrolytic capacitors required for intermediate storage, which can influence the service life of an electronic device through possible drying out. When using coolcept³-fleX inverters, the plant operator therefore has the prospect of a long service life.
In addition, a new, unique cooling concept inside the inverters guarantees an even distribution of heat and thus a long service life of the devices.

Product design and visualization

The StecaGrid has a graphic LCD display with which energy yield values, current performance and operating parameters of the system can be visualised. The innovative menu offers the possibility of an individual selection of the different measured values. A guided, pre-programmed menu ensures smooth, final commissioning of the device.


The lightweights with only 12 kg can be easily and safely mounted on the wall. The supplied wall bracket enables simple and very convenient installation. It is also not necessary to open the device for installation. All connections and the DC circuit breaker are accessible from the outside. For the DC connection, the Sunclix mating connectors are included in the scope of delivery.


Technical drawing: coolcept³ fleX StecaGrid 3213,StecaGrid 4013,StecaGrid 5013,StecaGrid 6013

Product features

  • Highest efficiency
  • Three-phase, symmetrical grid feeding
  • Simple installation
  • Integrated data logger
  • Low housing temperature at full load
  • Robust metal casing
  • Suitable for outdoor installation
  • Integrated DC circuit breaker
  • Very long service life
  • Droop Mode for integration in hybrid systems
  • Fixed voltage mode for other energy sources
  • Optimised shadow management using global MPP tracking


  • Multifunction graphical LC display with backlighting
  • Animated representation of yield


  • Simple menu-driven operation
  • Multilingual menu navigation



  •  coolcept³ fleX certificate EN – EN 50549-1 · pdf · 0.394 MB
  •  coolcept³ fleX certificate DE – VDE-AR-N 4105:2018-11 - NA Schutz · pdf · 0.476 MB
  •  coolcept³ fleX certificate Herstellererklärung IEC 61727:2004 - IEC 62116:2014 · pdf · 0.879 MB
  •  coolcept³ fleX certificate Zertifikat IEC / EN 62109-1:2010 / 62109-2:2011 EN · pdf · 0.479 MB
  •  coolcept³ fleX certificate DANSK ENERGI DK1/DK2:2019 EN · pdf · 0.461 MB
  •  coolcept³ fleX certificate DE – VDE-AR-N 4105:2018-11 - Einheitenzertifikat · pdf · 1.453 MB
  •  coolcept³ fleX certificate VDE-AR-N 4105:2018-11 DE - NA Schutz · pdf · 0.476 MB
  •  coolcept³ fleX certificate TOR Erzeuger Typ A:2019-12 DE - Unbedenklichkeitsbescheinigung · pdf · 0.221 MB
  •  coolcept³ fleX certificate EU Declaration of Conformity · pdf · 0.869 MB
  •  coolcept³ fleX certificate UNE 206007-1:2013 IN / UNE 206006:2011 IN ES · pdf · 0.261 MB

Commercial guarantee extension

  •  coolcept³ fleX commercial guarantee extension DE · pdf · 0.050 MB
  •  coolcept³ fleX commercial guarantee extension EN · pdf · 0.151 MB
  •  coolcept³ fleX commercial guarantee extension FR · pdf · 0.146 MB
  •  coolcept³ fleX commercial guarantee extension PL · pdf · 0.329 MB

Product data sheet

  •  coolcept³ fleX productdatasheet DE · pdf · 1,117 MB
  •  coolcept³ fleX productdatasheet EN · pdf · 1.117 MB
  •  coolcept³ fleX productdatasheet FR · pdf · 1,115 MB

Further downloads

  •  coolcept³ fleX download Herstellererklärung DE · pdf · 0.117 MB
  •  coolcept³ fleX download manufacturers declaration EN · pdf · 0.114 MB
  •  coolcept³ fleX download Flyer DE · pdf · 1.876 MB
  •  coolcept³ fleX download Flyer EN · pdf · 1.578 MB
  •  coolcept³ fleX download Länderzuordnung / Country Settings · pdf · 0.307 MB
  •  coolcept³ fleX download Herstellererklärung DE_ Maximaler Eingangsstrom und Kurzschlussstrom · pdf · 0.421 MB
  •  coolcept³ fleX download Manufacturer declaration max input current and short circuit current · pdf · 0.382 MB


  •  coolcept³ fleX manual Connecting energy meters EN · pdf · 1.385 MB
  •  coolcept³ fleX manual Anschluss Energiezähler DE · pdf · 1.308 MB
  •  coolcept³ fleX manual DA · pdf · 1.795 MB
  •  coolcept³ fleX manual DE · pdf · 2.077 MB
  •  coolcept³ fleX manual EN · pdf · 1.781 MB
  •  coolcept³ fleX manual ES · pdf · 1.807 MB
  •  coolcept³ fleX manual FI · pdf · 1.779 MB
  •  coolcept³ fleX manual FR · pdf · 1.807 MB
  •  coolcept³ fleX manual IT · pdf · 1.814 MB
  •  coolcept³ fleX manual NL · pdf · 1.795 MB
  •  coolcept³ fleX manual PL · pdf · 1.878 MB
  •  coolcept³ fleX manual SV · pdf · 1.787 MB

Technical data

 StecaGrid 3213StecaGrid 4013StecaGrid 5013StecaGrid 6013
DC input side (PV generator)
Maximum input voltage
1000 V
MPP voltage range
250 V … 800 V
Number of MPP tracker
Maximum input current
11.0 A
Maximum input power at maximum active output power
3300 W
4100 W
5110 W
6130 W
AC output side (Grid connection)
Grid voltage
320 V … 480 V (depending on regional settings)
Rated grid voltage
400 V
Maximum output current
7.0 A
7.0 A
10.0 A
10.0 A
Maximum active power (cos phi = 1)
3200 W
4000 W
5000 W
6000 W
Maximum apparent power
3200 VA
4000 VA
5000 VA
6000 VA
Rated power
3200 W
4000 W
5000 W
6000 W
Rated frequency
50 Hz and 60 Hz
45 Hz … 65 Hz (depending on regional settings)
Night-time power loss
< 3 W
Feeding phases
Total harmonic distortion (cos phi = 1)
< 1 %
Power factor cos phi
0.8 capacitive … 0.8 inductive
Characterisation of the operating performance
Max. efficiency
98.0 %
European efficiency
97.0 %
98.0 %
98.0 %
98.0 %
MPP efficiency
> 99.7 % (static), > 99 % (dynamic)
Own consumption
< 8 W
Power derating at full power from
50 °C (Tamb)
Isolation principle
no galvanic isolation, transformerless
Grid monitoring
yes, integrated
Residual current monitoring
yes, integrated (The design of the inverter prevents it from causing DC leakage current)
Operating conditions
Area of application
outdoors & indoors
Climate protection class as per IEC 60721-3-4
Ambient temperature
-15 °C … +60 °C
Storage temperature
-30 °C … +70 °C
Relative humidity
0 % … 100 %, non-condensating
Noise emission (typical)
29 dBA
Fitting and construction
Degree of protection
IP 65
Overvoltage category
DC Input side connection
Phoenix Contact SUNCLIX (1 pair), mating connector included
AC output side connection
Wieland RST25i5 plug, mating connector included
Dimensions (X x Y x Z)
399 x 657 x 222 mm
12.0 kg
Communication interface
RS-485 (1 x RJ45 sockets; connectable to Meteocontrol WEB‘log or Solar-Log™, Ethernet interface (1 x RJ45), Modbus RTU (1 x RJ45 socket: connectable to energy counter)
Integrated DC circuit breaker
yes, compliant with VDE 0100-712
Cooling principle
temperature controlled fan, variable speed, internal (dustproof)
Test certificate
see certificate download on the product page
coolcept, inverter family

Product overview coolcept inverters

All single-phase and three-phase coolcept inverters are extraordinarily cool, efficient and durable. In addition, all devices are extremely lightweight and quiet. Nevertheless there are differences for planners and users.more
coolcept, inverter, Topology

Steca's inverter topology coolcept

coolcept is Steca‘s new inverter topology that provides­ the highest peak efficiency. The patented coolcept topology is a global innovation that is only available from KATEK Memmingen.more
You are here: