50
51
※ 7.3 Maintenance
Danger
Risk of inverter damage or personal injury due to incorrect service!
Always keep in mind that the inverter is powered by dual sources: PV strings and utility
grid.
Before any service work, observe the following procedure.
① Disconnect the AC circuit breaker and then set the DC load-break switch of the
inverter to OFF;
② Wait at least 5 minutes for inner capacitors to discharge completely;
③ Verify that there is no voltage or current before pulling any connector.
Caution
Keep non-qualified persons away!
A temporary warning sign or barrier must be posted to keep non-qualified persons away
while performing electrical connection and service work.
Attention
Restart the inverter only after removing the fault that impairs safety performance.
Never arbitrarily replace any internal components.
For any maintenance support, please contact Sunways. Otherwise, Sunways shall not be
held liable for any damage caused.
Note
Servicing of the device in accordance with the manual should never be undertaken in
the absence of proper tools, test equipment or the latest revision of the manual which
has been clearly and thoroughly understood.
Items
Methods
Period
System clean
Check the temperature and dust of the inverter.
Clean the inverter enclosure if necessary.
Check if the air inlet and outlet are normal.
Clean the air inlet and outlet if necessary.
Six months to a year (it
d e p e n d s o n t h e d u s t
contents in air.)
※ 7.2 PV System for Ground Faults
If ground fault occurs, the inverter will beep, the red LED will light up and the Error
Message "GFCI Fault" will be displayed in the Results menu on the inverter user interface.
At the same time, the Sunways monitoring system will also issue an alarm.
8 Technical Parameters
Model
STT-4KTL
STT-4KTL-P
STT-5KTL
STT-5KTL-P
Input
Start-up Voltage (V)
200
180
200
180
Max. DC Input Voltage (V)
1,100
1,100
1,100
1,100
Rated DC Input Voltage (V)
620
620
620
620
MPPT Voltage Range (V)
200-950
160-1000
200-950
160-1000
No. of MPP Trackers
2
2
2
2
No. of DC Inputs per MPPT
1/1
1/1
1/1
1/1
Max. Input Current (A)
11/11
15/15
11/11
15/15
Max. Short-circuit Current (A)
15/15
20/20
15/15
20/20
backfeed current to the array (A)
0
0
0
0
Output
Rated Output Power (W)
4,000
4,000
5,000
5,000
Max. Output Power (W)
4,400
4,400
5,500
5,500
AC output rated apparent power(VA)
4,000
4,000
5,000
5,000
Max. Apparent Power (VA)
4,400
4,400
5,500
5,500
Rated Output Voltage (V)
3 / N / PE，230 / 400V
Rated AC Frequency (Hz)
50/60
50/60
50/60
50/60
AC output rated current（A）
6.7
6.7
8.4
8.4
Max. Output Current (A)
6.7
6.7
8.4
8.4
The measured Inrush current (A)
maximum output fault current (A)
33
33
33
33
maximum output overcurrent protection (A)
33
33
33
33
Power Factor
0.8 leading …0.8 lagging
Max. total harmonic distortion
< 3% @Rated Output Power
DCI
< 0.5%In
8 Technical Parameters
7 Troubleshooting
