Global Sources Stepup-Tech GTB Series User manual

Version：Rev 01
1/6
800W Grid micro inverter specification
1. Introduction
Stepup-Tech GTB series grid micro inverter, has high reliable performance, high
efficiency, with MPPT function, meanwhile installation is simple, and it’s very safe for user
since multi protection functions are implemented. It’s designed to directly connect to the power
grid in home for application, a Wifi module is built in as well, which can achieve online
monitoring by use together with smart life APP.
2. Features
Wide range input voltage, inverter directly connect to solar panels, with accurate MPPT
and APL function, can adjust the solar panel output power to the maximum to achieve
high conversion efficiency based on light.
AC 0 phase angle high precision detection, phase angle drift rate is less than 1% , thus
realized the AC output combine with city power together.
Synchronous high frequency modulation, in grid connected, parallel adjust output
phase angle to the same as city power. (For example, when the phase difference
between two AC is 0, merge two AC outputs), The inverter firstly rectify the 50Hz
full-wave AC to the 100Hz half-wave AC, then modulate the 100Hz half-wave with high
frequency wave to realize the high-frequency modulation.
Pure sine wave output, by using SPWM to generate pure sine wave directly.
Automatically adjustment for different power factor loads.
Constant current and constant power output
Automatically shuts down the output when power grid is fault.
Can be parallel used to increase output power

Version：Rev 01
2/6
3. Caution
Before installation, please read the specification carefully and check whether the
machine shell is damaged, and contact the supplier if you have any questions.
Before installation, you have to prepare suitable length of AC cable, and connect the
cable according to the color of the wire correctly if you want to extend cable (L Brown
wire-Live, N Blue wire-natural, G yellow wire-ground).
The inverter has to installed in the place with good shelter from rain and good
ventilation to avoid inverter overheating, meanwhile remove inflammable and explosive
materials around the machine.
There is a grounding mark on the machine, please connect the ground wire correctly.
Inverter input only can be connected to the solar panel, make sure the open circuit
voltage (VOC) and working voltage (VMP) of the solar panel meet the requirements in
the specification.
Do not disassemble the machine, only qualified maintenance person can repair the
machine.
When machine is in working, please avoid children to touch and play, to avoid electric
shock.
Do not disassemble the machine when it’s in working, do not cut the AC and DC cable
to avoid electric shock.
Machine is a grid-connected power generator, only can work when connect to the
power grid, when the power grid is fault it will stop work.
When machine is fault, first time is to disconnect the AC cable, remove the fault
machine, then connect the AC cable again.
When machine is in working, the surface temperature is high, so do not touch the
surface to avoid hurt, when the temperature is too high, the machine will went into the
over-temperature protection, and it will automatically back to work when temperature is
drop down.

Version：Rev 01
3/6
4. Technical parameter
Item Parameter
Input DC
Recommended solar panel input
power(W) 275-400W*2
Number of DC input
connections(group) MC4*2
Maximum DC input voltage 52V
Operating voltage range 20-50V
Start-up voltage 18V
MPPT tracking range 22-48V
MPPT tracking accuracy >99.5%
Maximum DC input current 12A*2
Output AC
Rated power output 750W
Maximum output power 800W
Rated output voltage 120VAC 230VAC
Output voltage range 90-160VAC 190-260VAC
Rated AC current 6.6A 3.47A
Rated output frequency 60Hz 50Hz
Output frequency range (Hz) 58.9-61.9Hz 47.5-50.5Hz
Power factor >0.99 >0.99
THD <5% <5%
Maximum number of branch
circuit connections 5 sets 10 sets
Efficiency
Maximum conversion efficiency 94%
CEC efficiency 92%
Night losses <80mW
Protection
Over/under voltage protection Yes
Over/under frequency protection Yes
Anti-islanding protection Yes
Over current protection Yes
Over load protection Yes
Over temperature protection Yes
Protection grad IP65
Number of indicator Working state LED 1pc，at front
side. WiFi signal LED 1pc，at DC
input side.
Communication mode Wifi/2.4G
Weight 1.85kg
Size (LxWxH) 31x20x3.8cm

Version：Rev 01
4/6
5. Environment
6. Safety and EMC
7. Picture
Item Parameter
Work temperature -40℃-+65℃
Storage temperature -40℃-+85℃
Humidity ≤95%
Altitude ≤2000m
Cooling method Natural cold
Place Indoor and outdoor（Shelter from rain）
Item Requirement Notes
Safety，EMC standard
EN61000-3-2,
EN61000-3-3,
EN62109-1/-2. EN55032,
EN55035, EN50438
Hi-pot
Input-Ground 500Vdc 1 minute, leakage
current≤10mA, no break
down and no spark.
Output-Ground 1500Vac
Input-Output 1500Vac
Insulation
resistance
Input-Shell ≥100MΩ@500Vdc
Output-Shell ≥100MΩ@500Vac
Input-Output ≥100MΩ@500Vdc

Version：Rev 01
5/6
8. Connection
Step 3. Open the cover of the AC output socket on inverter, plug AC cable to the AC
socket, as shown in below.
Step 4. Connect the AC cable to the AC main cable.
Step 5. Repeat steps 1 to 3, and install all inverters in parallel.
Step 6. Connect the AC cable to the power grid in your home to start your green energy
life.
Step 1. Install and fix the
inverter on the supporter of
the solar panel with the screws,
as shown in below.
Step 2. Connect corresponding
DC poles of PV into inverter
input, as shown in below.

Version：Rev 01
6/6
9. Accessories
Maintenance card 1copy， user’s manual 1copy， screw for installation 1bag， AC cable 1pc.
10. Package information
Single box for product，put it into the carton