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Solar On-Grid Inverter ST5KTL/ST6KTL/ST7KTL/ST8KTL User Manual Version 2.0 (EN)
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All rights to the content of this manual are owned by MOSO Power Supply Technology Co., Ltd (hereinafter “MOSO”). No part of this document can be modified, distributed, reproduced or published in any form or by any means without prior written permission from MOSO.
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.............. 2 6 VERVIEW OF THE ONNECTION (DC) .............. 2 7 ONNECTION OF THE RRAY 8.3.1 Conditions for DC Connection .............. 2 7 8.3.2 Assembling the DC Connectors .............. 2 8 8.3.3 Connecting the PV Array (DC) .............. 3 0 (AC) ................... 3 3 ONNECTION TO RID 8.4.1 Conditions for AC Connection .............. 3 3 8.4.2 AC Connection Procedure ................ ...
Inverter owners who will have the ability to interact with the inverter. 1.3 Safety 1.3.1 Application The ST5KTL/ST6KTL/ST7KTL/ST8KTL is a series of three phase on-grid inverter, which main function is to convert the DC current from PV strings into AC current and feed it into grid.
A.PV Strings B. ST5-8KTL C. AC Distribution Unit D. Grid Figure 1 Principle of a PV Plant with ST series inverter 1.3.2 Safety Instructions Safety symbols used in this manual, which highlight potential safety risks and important safety information, are listed as follows: CAUTION: Risk of electric shock.
Warning! Please do not connect PV array positive or negative to ground, it could cause serious damage to the inverter. PV module used with inverter must have an IEC 61730 Class A rating. Warning! • Ensure that input DC voltage is less than max. DC voltage.
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Symbol Description Danger of high voltage! R esidual voltage will vanish in 5 minutes after the inverter disconnected. Open the front cover of the inverter at least 5 minutes after disconnecting. Beware of hot surface! The inverter can get hot during operation. Avoid ...
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You can operate the interface by tapping on it. • Tapping once: The background illumination switches • Tapping again: Updating information. You can operate the interface by pressing buttons. For more information on operating the buttons, refer to Section 7.2 ‘LCD display’. Recovery and recycling.
2 Introduction 2.1 Overview The image shown here is for reference only. The actual product you receive may differ. Figure 2 Stereogram 2.2 Electrical Block Diagram · Electrical block diagram Figure 3 Electrical block diagram...
2.3 Product Instruction Figure 4 Name Description The DC switch can disconnect DC Switch strings inverter safely ST Series Inverters have two independent MPP trackers PV1 and PV Terminals PV2. Per tracker has input terminals. Terminals connect the WiFi Terminal WiFi module or GPRS module.
internal. AC Terminals AC output The display shows the status information (e.g. working status, LCD Display power, input voltage) as well as errors and disturbances. 2.4 Dimension and Weight · Dimension...
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·List Table 2 3 Packaging List Item Name Quantity Solar Inverter Mounting Frame expansion bolt PV connector plug bolt plug bolt RS485 connector User Manual The ST series inverter is shipped with the following items:...
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逆 变 器 用 户 手 册 Figure · Identifying g the Invert u can identif fy the invert ter by the n ameplate. T The namep plate is loca ated on the right-hand side of the housing. e inverter ty pe (type/mo odel), seria l number (s...
4 Technical Data 4.1 Input(DC) Table 3 Inverter Model ST5KTL ST6KTL ST7KTL ST8KTL Input(DC) Max DC power 7500 W 9000 W 10500 W 12000 W Max DC voltage 1100 V Start voltage 160 V MPPT voltage range 200-950 V Rated input voltage...
4.2 Output(AC) Table 4 Inverter Model ST5KTL ST6KTL ST7KTL ST8KTL Output(AC) Rated output power 5 kW 6 kW 7 kW 8 kW Rated output voltage 3/N/PE~230V/400V AC voltage range 310~480 V(Conform to local standards) Rated AC grid frequency 50Hz/60Hz Max output current Adjustable power factor 0.8leading-0.8lagging...
>99.9% >99.9% >99.9% >99.9% Protection DC Switch DC reverse polarity protection DC surge protection Insulation monitoring AC overcurrent protection AC surge protection Anti-islanding protection Residual current monitoring 4.4 General Data Table 6 Inverter Model ST5KTL ST6KTL ST7KTL ST8KTL General data...
Inverter logs essential data including running information and error records. 【Parameter configuration】 Inverter provides various parameter configurations for optimal operation. 【Communication interface】 You can choose the RS485 terminal for connecting a communication module to the PV system, such as Wi-Fi module. 【Protective function】...
Figure 7 NOTICE! The inverter output power decrease is usual in the condition of thermal protection, but if it occurs frequently, you need to check the heat sink or consider putting the inverter in the place where have better air flow, and if output power decreases caused by electrical problem, please ask for professional supports.
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• Some parts of the inverter will be hot during operation. ·Open the package Check the inverter and accessories according to the pack list. If the inverter is damaged or any accessory missing, please contact the local distributor. 7.2 Installation site selection The following must be considered when selecting the location for an inverter: ...
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Figure 8 Installation • Mount the inverter at eye level. Given the weight of the device, this will facilitate disassembly if service work is necessary. • The ambient temperature should be lower than 40°C to achieve optimal performance. • Do not expose the inverter to direct sunlight as this can cause excessive heating and thus power reduction.
Figure 9 • If multiple inverters are mounted in areas with high ambient temperatures, increase the clearances between the inverters and ensure an adequate fresh-air supply. This will prevent a reduction in inverter power as a result of excessively high temperatures (details on temperature derating can be found in the Technical Information).
7.4 Fixed the Mounting on the Wall Space for heat dissipation should be reserved while installing the inverter. Install the inverter with good ventilation condition. Figure 11 Align the wall mounting bracket horizontally on the wall with the arrow upwards. Mark the position of the drill holes. Drill the marked holes.
Fasten the inverter into the T slot. Figure 14 7.6 Check Inverter Installation Status • Check the upper straps of Inverter to ensure it fixed on to the bracket. • Check the secure mounting of the PV-Inverter by trying to raise it from the bottom.
8 Electrical Connection 8.1 Safety NOTICE! Electrostatic discharge can damage the inverter. • Internal components of the inverter can be irreparably damaged by electrostatic discharge. • Earth yourself before touching any components. 8.2 Overview of the Connection Area Figure 15 Table 7 Object Description...
8.3 Connection of the PV Array (DC) 8.3.1 Conditions for DC Connection The inverter has two PV input terminals, "PV1" and "PV2", each of them connects two strings. Up to four strings can be connected in total. • Requirements for the PV strings: –...
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he open circ cuit voltage of the PV s strings cann not exceed e maximum m input volta age of the in nverter. Maximum input Maxim mum input current pe er MPP voltag trac cker 1,100 V ( (DC) 22 A (DC) o mixed PV V connectio...
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Figure 17 Connection steps: 1. Turn of the DC switch and make sure it will not be turned on accidentally. 2. Strip the insulation layer and protective sleeve of the cable, and leave the bare cooper conductor in 7mm. Fugure 18 3.
Fugure 20 6. Screw the end cap with a torque of 2.6~2.9NM. Fugure 21 7. Connect the connectors with the inverter terminals when there is a “click” sound. Fugure 22 8. Using a wrench to take apart the connection when it is necessary.
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NOTICE Over vo ltages wou uld damage e the multi meter. DC input vo oltage rang ge of the mu ultimeter shou uld be over 1,000 Vdc. Turn off D DC input by y turning the e DC switch h to OFF (see fig 2 25).
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Figur re 25 Check and d make sure e the PV str rings are no ot grounded d. Refer to Section 1.3 3.3 ‘note’. Check the polarity of the PV mod dule output matches th he polarity of the inve erter connec ctor.
The PV co onnectors a are IP68, bu ut can’t be e exposed to water for a a long time. 4 Conne ection t o Grid ( (AC) 4.1 Cond ditions fo or AC Co onnectio u must comp ply with the e connection n requireme ents of your...
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be equipped with a three phase 4P micro circuit breaker (hereinafter MCB). A MCB can disconnect Line L1/L2/L2/N of AC output with the live wire/zero wire of grid. Install the MCB where is easy to access to and operate. DANGER! Danger to life due to fire.
• A screw fuse can only use as circuit protection instead of a load disconnecting device. • Please use a isolating switch or a MCB as load disconnecting device. 8.4.2 AC Connection Procedure Check if the grid voltage and frequency accordant with the inverter setting (refer to Section 4.2"Output"...
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Figure 29 AC terminals Connect L1, L2, L3, N and the protective conductor (PE) to the AC terminal in accordance with the labeling (see fig 30). – To do this, the PE insulated wire must be 5 mm longer than the L and N insulated conductors.
Figure 31 DANGER! Danger to life due to high voltages in the inverter. • Do not switch on the miniature circuit-breaker until the PV array has been connected and the inverter is securely closed. 9. Operation 9.1 LED Display There are three LED indicators on the panel: Six buttons...
Figure 32 9.1.1 DC/DC status LED 1 (Green) Table 9 The DC/DC circuit is off. Blinking The DC/DC circuit starts. The DC/DC circuit is working normally...
9.1.2 DC/AC status LED 2(Green) Table 10 The DC/AC circuit is off. Blinking The DC/AC circuit starts. The DC/AC circuit is working normally. 9.1.3 Fault LED 3 (Red) Table11 No error occurs The inverter is in fault status Normally, after starting up, DC/DC LED and DC/AC LED will light which indicates that the inverter is feeding electricity to the grid.
below, the LCD will show next page by a single tap or press the left or right button. Figure 34 Summary diagram 9.2.1 System Page Figure 35 Power: the present power feeding into the grid; Today: Energy exports to the grid in the present day, and updates the data every 10 minutes;...
Testing Mode, On-grid Mode, and Fault Mode; Event: If the inverter reports warnings, the display will show up Warning, and the report can be found in next page. Warning will be eliminated and the display in this page will be blank. 9.2.2 Message Page Figure 36 The system status is shown on the page of MESSAGE.
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RC chip Fault Aux Power Fault Over Temp Fault Pv1 Iso Fault Pv2 Iso Fault PLL Fault Viso Power Fault Bus Volt Low Fault Bus Un Balance Bus Ovp Fault Ocp Ac Ocp Boost IAC_ RMS_ Unbalance DCI Gird over limit GFCI Fault Pv Config Set Wrong Unrecover Phase Sequence Fault...
10 Setting up Communication 10.1 Communication Terminal Types MOSO ST6/7/8KTL can use RS485 and WiFi for communication. 10.2 Communication 10.2.1 RS485 · RS485 Communication (Applied to one inverter or multiple inverters) In general, RS485 can be used for the communication with up to 32 units.
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Figure 37 Figure 37 Communication Interface of ST Series Inverters Figure 38 8-line RJ45 Table13 8-line RJ45 8-line RJ45 Wire Function Wire Color Orange white Orange Green white Blue Blue white Green...
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Brown w white Brow · C Connectio n method b between R RS485 and W Webbox mmunicatio n cables a are used f for connec ction amon g the ST inve erters. A cro ossover cab ble is used to connect t the inverte er with the bbox.
Figure .2.2 Buil ld-in WiF Fi (optio onal) e WiFi comm munication function is only applica able if the in nverter a WiFi mo dule. The W WiFi module e is built-in a and installe ed in the inve erter before shipment f from the ma anufacturer...
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corresponding solutions. Table 14 Troubleshooting list Faults Diagnosis and Solutions -Waiting for one minute until the grid goes back to normal working status. - Check if the grid voltage and frequency complies with the standards setting. -Call the local service office. Grid Failure -Off to grid.
—Check if the size and length of all cables is proper. —Check if the connection of output terminals and wiring is proper. —Check if the configuration setting is proper. —Check if the connection between the display board and the communication cable is proper. 12 Decommissioning 12.1 Dismantling ●...
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13 Warranty MOSO offers 5-year warranty starting from the inverters delivering from the manufacturer’s warehouse. Warranty certificate represents a five year warranty service for mentioned products since the date of purchase. Warranted Products This warranty is applicable solely to the following products:...