Huawei SUN2000 Solar Inverter Quick Guide
Models Covered: SUN2000-(75KTL-M1, 100KTL-M2, 110KTL-M2, 115KTL-M2)
Issue: 02
Part Number: 31500JMM
Date: 2023-09-22
Published by HUAWEI TECHNOLOGIES CO., LTD.
Important Safety Information and Notices
- Before installation, thoroughly read the user manual for product information and safety precautions. Failure to follow storage, transportation, installation, and usage guidelines may void the warranty. Access the user manual and safety precautions via Huawei Enterprise Support.
- Information in this document is subject to change without notice. While efforts are made to ensure accuracy, statements and recommendations do not constitute an express or implied warranty.
- Danger, Warning, Caution, and Notice statements in this document do not cover all safety precautions. Comply with relevant international, national, or regional standards and industry practices.
- Only qualified professionals or trained personnel should operate the equipment. Personnel must understand the system, its working principles, and relevant standards.
- During operations, use insulated tools and wear personal protective equipment (PPE) such as protective clothing, insulated shoes, goggles, safety helmets, and insulated gloves.
1 Overview
Appearance
The solar inverter features:
- (1) Panel: The main body of the inverter.
- (2) LED indicators: Visual indicators for status.
- (3) Maintenance compartment door: Provides access to internal components.
- (4) Mounting bracket: For securing the inverter.
- (5) External fan tray: For cooling.
Port Description
The inverter has various ports:
- DC Input Terminal Groups: Controlled by DC switches. Group 1 (PV1–PV8) is controlled by DC SWITCH 1.
- DC Switches: Three switches (DC SWITCH 1, 2, 3) for controlling DC power.
- Reset Buttons: Reset buttons 1, 2, and 3 are associated with their respective DC switches.
- USB Port: For data access or firmware updates.
- Communications Port (COM): For data communication.
- Holes for Cables: For AC output power cable and tracking system power cable.
- Ventilation Valve: For air circulation.
DC Switch Description
The DC switches have three states:
- ON: The DC switch is ON and can automatically turn off for protection.
- OFF: The DC switch is OFF.
- RESET: When a DC switch automatically turns off due to a fault (indicated by a steady red LED4), the RESET button will be released. The switch can only be moved to the unloaded position (indicated by a specific symbol, e.g., a green arrow pointing to 'OFF') and cannot be set to ON until the fault is resolved.
WARNING: If DC switches turn OFF automatically due to a fault, contact technical support. Do not attempt to turn them ON yourself.
2 Installation Requirements
NOTICE: If inverters are installed in areas with abundant vegetation, harden the ground underneath using cement or gravel (recommended area: 3 m x 2.5 m) in addition to routine weeding.
Angle
The inverter should be installed at an angle, typically not exceeding 15 degrees from the vertical for optimal performance and drainage.
Clearance
Ensure adequate clearance around the inverter:
- Minimum 200 mm above.
- Minimum 600 mm to the sides and rear.
- Recommended clearance underneath: 600-730 mm.
3 Installing a Solar Inverter
Dimensions
The inverter has specific dimensions for installation planning:
- Front View: Width approximately 1035 mm, height approximately 700 mm, depth approximately 387.5 mm. Mounting bracket dimensions are also provided.
- Side View: Depth approximately 387.5 mm, height approximately 700 mm.
Installation Steps
- Install the mounting bracket: It is recommended to apply anti-rust measures to the drilling hole positions.
- Install the solar inverter onto the mounting bracket: Secure the inverter using the provided M12 bolts.
- Tighten security Torx screws: Ensure screws are tightened to the specified torque (e.g., 45 N-m for M12 bolts).
NOTICE: Handles are optional and provided separately for easier installation. Ensure they are securely installed during the process and removed once installation is complete.
Note: The M12x40 bolt assemblies are included. If longer bolts are needed, source them separately. Remove and set aside the security Torx wrench before installing the mounting bracket.
4 Connecting Cables
WARNING: Do not connect loads between the inverter and the AC switch directly connected to it, as this may cause the switch to trip. If using an AC switch with specifications beyond local standards or recommendations, it might fail to turn off promptly during exceptions, leading to serious faults.
NOTICE: Each inverter requires its own AC output switch. Multiple inverters cannot share a single AC output switch. Connect an AC switch to the AC side of the inverter for safe disconnection from the power grid during exceptions. Select an appropriate AC switch based on local industry standards and regulations.
NOTICE: Connect cables according to local installation laws and regulations. Leave sufficient slack before connecting cables to ports to prevent overstress and poor connections.
4.1 Preparations
Note:
- S and Sp denote the conductor cross-sectional areas for AC power cables and PE cables, respectively.
- Cable size must comply with local standards.
- Cable selection depends on factors like rated current, cable type, routing mode, ambient temperature, and expected line loss.
Cable Description
| No. | Cable | Type | Conductor Cross-Sectional Area | Outer Diameter |
|---|---|---|---|---|
| 1 | PE cable[1] | Outdoor cable and M10 OT/DT terminals | Sp ≥ S/2 | - |
| 2 | Tracking system power cable | Three-core outdoor copper cable with dual-layer protection | 10 mm² | 15–18 mm |
| 3 | AC output power cable (multi-core) | For 3-core (L1, L2, L3) without neutral: Use outdoor cable and M12 OT/DT terminals. | Copper cable: S: 70–240 mm² Sp ≥ S/2 Aluminum alloy cable or copper-clad aluminum cable: S: 95–240 mm² Sp ≥ S/2 | 24–66 mm |
| For 4-core (L1, L2, L3, PE) without neutral: Use outdoor cable, M12 OT/DT terminals (L1, L2, L3), and M10 OT/DT terminals (PE). | ||||
| For 4-core (L1, L2, L3, N) with neutral: Use outdoor cable and M12 OT/DT terminals (L1, L2, L3, and N). | ||||
| For 5-core (L1, L2, L3, N, PE) with neutral: Use outdoor cable, M12 OT/DT terminals (L1, L2, L3, and N), and M10 OT/DT terminals (PE). | ||||
| 4 | AC output power cable (single-core) | Single-core outdoor cable and M12 OT/DT terminals. | Copper cable: S: 70–240 mm² Aluminum alloy cable or copper-clad aluminum cable: S: 95–240 mm² | 14–32 mm |
| 4 | DC input power cable | PV cable meeting 1100 V standard | 4–6 mm² | 5.5–9 mm |
| 5 | RS485 communications cable | Outdoor shielded twisted pair | 0.25–1 mm² | One or two communication cables: 4–11 mm Three communication cables: 4–8 mm |
Note [1]: Sp value is valid if PE and AC power cable conductors use the same material. If materials differ, ensure the PE cable conductor provides equivalent conductance. PE cable specifications are subject to this table or calculated per IEC 60364-5-54.
4.2 Installing a PE Cable
Note:
- Connect the PE cable to a nearby ground point. Ensure equipotential connections for all solar inverters in an array.
- To enhance corrosion resistance of the ground terminal, apply silica gel or paint after connecting the PE cable.
Diagram shows connecting the PE cable to the reserved PE point using an M10 terminal, tightened to 15 N-m.
4.3 Opening the Maintenance Compartment Door
WARNING:
- Do not open the solar inverter panel.
- Before opening the compartment door, turn off the AC output switch and all three DC switches.
- Avoid opening the compartment door on rainy or snowy days. If necessary, take protective measures against moisture ingress.
- Do not leave unused screws inside the compartment.
- Loosen the screws on the maintenance compartment door.
- Open the maintenance compartment door and adjust the support bar.
- Remove any accessories and set them aside.
- Select the appropriate crimping module based on the AC output power cable type (multi-core or single-core).
4.4 Removing the Rubber Rings from the Crimping Module
Use scissors to cut the joints of the rubber rings to remove them. Ensure the correct rubber rings are removed according to the cable diameter range to avoid damaging the crimping module, which could affect the inverter's protection level.
4.5 (Optional) Installing the Tracking System Power Cable
NOTICE:
- The tracking system requires an overcurrent protective device. The cable length between the power cable terminal and this device must be ≤ 2.5 m.
- The tracking system power supply should be an AC three-phase grid.
- Keep flammable materials away from the power cable.
- Protect the power cable with a conduit to prevent short circuits from insulation damage.
Diagram shows cable preparation (stripping length, diameter D: 15-18 mm) and connection to terminals using M6 screws tightened to 6-8 N-m.
4.6 Installing the AC Output Power Cable
NOTICE:
- Measure cable outer diameter using the ruler sticker in the compartment.
- Ensure the AC output power cable is securely fastened to prevent inverter malfunction or terminal block damage due to overheating.
- Provide sufficient slack in the PE cable so it bears pulling force last.
- If a compartment door screw is lost, use the spare screw from the fitting bag.
Multi-core Cable Connection Method
Diagrams illustrate cable preparation (stripping length L+3 mm) and connection for various cable diameters (D: 24-66 mm) to M12 (L1/L2/L3) and M10 (PE) terminals. Correct and incorrect connection indicators are shown. Torques: M12 (25-30 N-m), M10 (15 N-m).
Single-core Cable Connection Method
Diagrams illustrate cable preparation (stripping length L+3 mm) and connection for various cable diameters (D: 14-32 mm) to M12 terminals. Correct and incorrect connection indicators are shown. Torque: M12 (25-30 N-m).
Cable Connections
Diagrams show the correct wiring for:
- Five-core cable
- Four-core cable (including PE)
- Four-core cable (including N)
- Three-core cable
- Single-core cable (including N)
- Single-core cable (excluding N)
Diagrams also show the process for closing the maintenance compartment door, securing it with M6 screws tightened to 5 N-m.
4.7 Installing DC Input Power Cables
Selecting DC Input Terminals
WARNING: Before connecting PV strings, check PV string output insulation to ground. Use an insulation resistance tester with 1500 V between the PV- cable and ground. Resistance should be ≥ 1 MΩ. Troubleshoot if less than 1 MΩ.
When DC inputs are not fully configured, follow these requirements:
- Distribute DC input power cables evenly across DC input terminals controlled by the three DC switches; DC SWITCH 1 is preferred.
- Prefer even-numbered PV terminals for maximum MPPT connections.
- For 11 to 19 PV inputs, connect to odd-numbered PV terminals (PV1 to PV19), avoiding adjacent MPPTs if possible.
The table below details DC input terminal selection for 11 to 19 PV inputs across SWITCH 1, SWITCH 2, and SWITCH 3, mapping to MPPTs.
| Number of PV Inputs | SWITCH 1 | SWITCH 2 | SWITCH 3 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| MPPT1 | MPPT2 | MPPT3 | MPPT4 | MPPT5 | MPPT6 | MPPT7 | MPPT8 | MPPT9 | MPPT10 | |
| 11 | PV2, PV1 | PV4, PV2 | PV6, PV3 | PV8, PV4 | PV10, PV5 | PV12, PV6 | PV14, PV7 | PV16, PV8 | PV18, PV9 | PV20, PV10 |
| 12 | PV2 | PV4 | PV6 | PV8 | PV10 | PV12 | PV14 | PV16 | PV18 | PV20 |
| 13 | PV1 | PV2 | PV4 | PV6 | PV8 | PV10 | PV12 | PV14 | PV16 | PV18, PV19 |
| 14 | PV1 | PV2 | PV4 | PV6 | PV8 | PV10 | PV12 | PV14 | PV16, PV18 | PV20, PV19 |
| 15 | PV1 | PV2 | PV4 | PV6 | PV8 | PV10 | PV12 | PV14, PV16 | PV18, PV20 | PV19 |
| 16 | PV1 | PV2 | PV4 | PV6 | PV8 | PV10 | PV12, PV14 | PV16, PV18 | PV20, PV19 | |
| 17 | PV1 | PV2 | PV4 | PV6 | PV8 | PV10, PV12 | PV14, PV16 | PV18, PV20 | PV19 | |
| 18 | PV1 | PV2 | PV4 | PV6, PV8 | PV10 | PV12, PV14 | PV16, PV18 | PV20, PV19 | ||
| 19 | PV1 | PV2, PV3 | PV4, PV5 | PV6, PV7 | PV8, PV9 | PV10, PV11 | PV12, PV13 | PV14, PV15 | PV16, PV17 | PV18, PV19, PV20 |
Connecting DC Input Power Cables
NOTICE:
- Use only Amphenol Helios H4 metal contacts and DC connectors supplied with the inverter. Incompatible parts can cause serious damage, not covered by warranty.
- Label cable polarities before connecting DC input power cables to prevent inverter damage.
- Measure DC input voltage with a multimeter. A negative value indicates incorrect polarity. If voltage exceeds 1100 V, too many PV modules are in a string; remove some.
- If a DC input cable is connected in reverse and DC switches are ON, do not operate switches or connectors. Wait for low irradiance, turn DC switches OFF, then correct connections. Damage from reverse connection is not covered by warranty.
- Connect PV string connectors to inverter connectors and pull back axially to ensure a secure connection.
- Secure connections are mandatory; improper connections are not covered by warranty.
Diagrams illustrate:
- Preparation of positive and negative metal contacts (8-10 mm strip length).
- Crimping using H4TC0003 (Amphenol) ensuring the cable cannot be pulled out.
- Connecting positive and negative connectors, ensuring a 'click' sound.
- Using a multimeter to measure DC voltage (should be ≤ 1100 V).
- Ensuring the locking nut (H4TW0001, Amphenol) is secured.
4.8 Installing RS485 Communications Cables
NOTICE:
- The inverter supports RS485 and MBUS communication. MBUS mode does not require connection to the RS485-1 port.
- This section details connecting three communication cables.
- Route communication cables separately from power cables to avoid interference.
Pin Definitions of Communications Ports
Diagram shows an 8-pin connector with pin assignments:
- RS485-1: Pins 1 (RS485A IN), 3 (RS485B IN), 5 (PE, shielding ground). Pins 2 (RS485A OUT), 4 (RS485B OUT) are for cascading or connecting to devices like SmartLogger.
- RS485-2: Pins 7 (RS485A), 8 (RS485B) for connecting to RS485 slave devices. Pins 6 (PE, shielding ground).
Connecting RS485 Communications Cables
Diagrams show the process for connecting RS485 cables using 4-8 mm rubber plugs (four-hole, two-hole, or three-hole). This involves cable preparation (stripping length D), inserting into the plug, and securing with M3 screws (0.5 N-m torque) and a 3 N-m torque for the main connector. The number of communication cables (1, 2, or 3) dictates the plug configuration.
5 Verifying the Installation
Ensure the following acceptance criteria are met:
- The solar inverter is installed correctly and securely.
- DC switches and the downstream AC switch are set to OFF.
- All cables are connected correctly and securely.
- The installation space is proper, clean, and tidy.
- The maintenance compartment door is closed and its screws are secured.
- Unused DC input terminals are sealed.
- Unused USB ports are plugged with watertight caps.
6 Powering On the System
WARNING: When LED2 is steady green (indicating grid-tied status), do not turn on any DC switch. This could damage the inverter if insulation resistance is not detected.
NOTICE:
- Before turning on the AC switch, verify the AC voltage is within the specified range using a multimeter.
- Do not turn the DC switch to the unloaded position.
- Turn on the AC switch between the solar inverter and the power grid.
- Set DC SWITCH 1 (MAIN SWITCH) to ON. Listen for a click.
- Check the PV connection indicator. If it is steady green, set DC SWITCH 2 and DC SWITCH 3 to ON.
- Observe the LED indicators for operating status.
Indicator Status and Meanings
| Indicator | Status (Blinking Fast: On for 0.2s & Off for 0.2s; Blinking Slowly: On for 1s & Off for 1s) | Description |
|---|---|---|
| PV connection indicator | Steady green | At least one PV string is properly connected, and DC input voltage of the corresponding MPPT circuit is ≥ 200 V. |
| Blinking green fast | If Alarm/Maintenance indicator is red, an environmental fault at the DC side is generated. | |
| Off | Solar inverter disconnects from all PV strings, or DC input voltage of all MPPT circuits is < 200 V. | |
| Grid connection indicator | Steady green | Solar inverter is in grid-tied mode. |
| Blinking green fast | If Alarm/Maintenance indicator is red, an environmental fault at the AC side is generated. | |
| Off | Solar inverter is not in grid-tied mode. | |
| Communications indicator | Blinking green fast | Solar inverter receives communication data normally. |
| Off | Solar inverter has not received communication data for 10 seconds. | |
| Alarm/ Maintenance indicator | Alarm status: Steady red | A major alarm is generated. If PV or Grid connection indicator blinks green fast, troubleshoot DC/AC faults via SUN2000 app. If both indicators are not blinking green fast, replace components or inverter as instructed by the SUN2000 app. |
| Blinking red fast | A minor alarm is generated. | |
| Blinking red slowly | A warning alarm is generated. | |
| Local maintenance status | Steady green | Local maintenance succeeds. |
| Blinking green fast | Local maintenance fails. | |
| Blinking green slowly | Solar inverter is in local maintenance or shut down via command. |
7 Commissioning
Note:
- The FusionSolar app is recommended for connection to the FusionSolar smart PV management system. The SUN2000 app is recommended for other management systems.
- Both apps communicate via WLAN, Bluetooth, or USB data cable for alarm query, parameter settings, and maintenance.
- Download apps from the Huawei app store (appstore.huawei.com) or scan QR codes.
NOTICE: Screenshots are for reference only; actual screens may vary. For WLAN connection, the initial hotspot name is 'Adapter-WLAN module SN' and password is 'Changeme'. Set a strong, unique login password upon first use and change it periodically for security. Lost passwords may prevent device access. The Company is not liable for losses due to password issues. Set the correct grid code based on the application area.
Scenario: Connecting to FusionSolar Smart PV Management System
- Open the FusionSolar app and log in using an installer account (e.g., to intl.fusionsolar.huawei.com).
- Navigate to Me > Device commissioning.
- Connect to the device: Scan the QR code on the WLAN/Bluetooth module, or connect manually via WLAN hotspot, Bluetooth, or USB.
- Enter the login password.
- Tap 'Log in' to access the Quick Settings or solar inverter screen.
Scenario: Connecting to Other Management Systems
- Open the SUN2000 app.
- Connect to the device: Scan the QR code on the WLAN/Bluetooth module, or connect manually via WLAN hotspot, Bluetooth, or USB.
- Enter the login password.
- Tap 'Log in' to access the Quick Settings or solar inverter screen.
Company Information
Huawei Technologies Co., Ltd.
Huawei Industrial Base, Bantian, Longgang
Shenzhen 518129 People's Republic of China
Huawei Enterprise: Accelerate Industrial Intelligence
support.huawei.com/enterprise
