Qoltec Hybrid Solar Inverter Off-Grid User Manual
Models: 53863, 53864
Introduction
Thank you for choosing our solar inverter. This manual will guide you through the setup, operation, and troubleshooting of your device. Please read this manual carefully before installation and operation.
About This Manual
This manual covers the assembly, installation, operation, and troubleshooting of the hybrid solar inverter. It includes safety and installation instructions, as well as information on tools and wiring.
About the Product
This is a multifunctional inverter that combines inverter, solar charger, and battery charger functions, providing uninterrupted power support in one package. The versatile LCD display offers user-configurable and easily accessible button operations, such as battery charging current, AC or solar charging priority, and allowable input voltage according to different applications.
Installation
I. Preparation
Before installation, inspect the unit for any damage. The package should contain the solar inverter and the user manual. Remove the bottom cover by unscrewing three screws to access the wiring terminals.
II. Unit Installation
Consider the following points when selecting an installation location:
- Do not mount the inverter on flammable building materials.
- Mount the inverter on a solid surface.
- Install the inverter at eye level for easy visibility of the LCD display.
- The ambient temperature should be between 0°C and 55°C for optimal performance.
- The recommended mounting position is vertically against a wall.
- Ensure adequate clearance around the unit for heat dissipation and cable routing as shown in the illustration.
NOTE: Suitable for mounting on concrete or other non-combustible surfaces only.
Mount the unit by tightening three screws. M4 or M5 screws are recommended.
III. Battery Connection
NOTE: For safe operation and compliance, install separate DC overcurrent protection or a disconnecting device between the battery and the inverter. Current protection is always required.
WARNING: All electrical work must be performed by qualified personnel.
WARNING: Use the correct cable for battery connection to ensure system safety and efficient operation. Refer to the table for recommended cable size, stripping length (L2), and tinning length (L1).
| Model | Max. Current | Battery Capacity | Cable Size | Cable mm² | L1 (mm) | L2 (mm) | Rated Torque |
| 1500W-24 | 70A | 100AH | 6AWG | 13.3 | 3 | 18 | 2~3 Nm |
| 2500W-24 | 100A | 100AH | 4AWG | 21.15 | 3 | 18 | 2~3 Nm |
| Other models | 140A | 100AH | 2AWG | 38 | 3 | 18 | 2~3 Nm |
Battery Connection Steps:
- Strip 18 mm of insulation from the positive and negative conductors.
- Connect all batteries according to the unit's requirements. Use batteries with the recommended capacity.
- Insert the battery cable flat into the inverter's battery connector, ensuring screws are tightened to the specified torque. Observe correct polarity and ensure cables are securely fastened.
WARNING: Risk of electric shock due to high battery voltage.
NOTICE: Do not place anything between the flat part of the inverter terminal and the connector to prevent overheating.
NOTICE: Do not apply antioxidant to the terminals before proper connection.
NOTE: Ensure correct polarity (+ to + and - to -) before final DC connection or closing the DC switch.
IV. AC Input/Output Connection
NOTE: Install a separate AC switch between the inverter and the AC source before connecting. This allows safe disconnection during maintenance and protects the AC input from overcurrent. A 50A switch is recommended.
NOTE: Do not interchange the input ('IN') and output ('OUT') terminal blocks.
WARNING: All wiring work must be performed by qualified personnel.
WARNING: Use the correct cable for AC input connection for system safety and efficiency. Refer to the table for recommended cable size.
| Model | Cross Section | Torque Value |
| 1.5KVA | 12AWG | 1.4 ~ 1.6 Nm |
| 2.5KVA/3.5KVA | 10AWG | 1.4 ~ 1.6 Nm |
| 5.5KVA | 8 AWG | 1.4 ~ 1.6 Nm |
AC Input/Output Connection Steps:
- Ensure the DC switch is open before connecting AC input/output.
- Strip 10 mm of insulation from six conductors. Shorten the phase conductor (L) and neutral conductor (N) by 3 mm.
- Insert AC input conductors according to polarity indicated on the terminal block and tighten the terminal screws. Connect the protective earth conductor (PE) first (Yellow-Green), then Line (L - Brown), and Neutral (N - Blue).
Notice: Ensure the AC power source is disconnected before attempting connection.
- Connect the AC output conductors according to polarity indicated on the terminal block and tighten the terminal screws. Connect the protective earth conductor (PE) first.
Wiring Diagram: PE (Yellow-Green) to Grounding, L (Brown) to Line, N (Blue) to Neutral.
NOTE: Appliances like air conditioners require a 2-3 minute delay for restart to allow refrigerant pressure to equalize. If power fails and restores quickly, connected appliances may be damaged. Check with the appliance manufacturer for a time-delay function. Otherwise, this inverter/charger may trigger an overload fault and disconnect the output, potentially causing internal damage.
V. PV Connection
NOTE: Install a DC breaker between the inverter and PV modules before connecting.
CAUTION: All wiring must be performed by qualified personnel.
WARNING: Use the correct cable size for PV module connection for system safety and efficiency.
| Model | Typical Current | Cable Size | Torque |
| 1.5 KVA | 15 A | 12 AWG | 1.4 ~ 1.6 Nm |
| 2.5KVA | 15 A | 12 AWG | 1.4 ~ 1.6 Nm |
| 3.5KVA | 15 A | 12 AWG | 1.4 ~ 1.6 Nm |
| 5.5KVA | 18 A | 12 AWG | 1.4 ~ 1.6 Nm |
| 6.2 KVA | 27 A | 12 AWG | 1.4 ~ 1.6 Nm |
PV Module Selection:
Consider the following parameters when selecting PV modules:
- The open-circuit voltage (Voc) of the PV modules must not exceed the inverter's maximum open-circuit voltage.
- The open-circuit voltage (Voc) of the PV modules should be higher than the minimum battery voltage.
| Solar Charging Mode | |||
| INVERTER MODEL | 1.5KW-3.5KW | 5.5KVA | |
| Max. PV Array Open Circuit Voltage | 500VDC | 500VDC | |
| PV Array MPPT Voltage Range | 30VDC 500VDC | 60VDC 500VDC | |
| Max. PV INPUT CURRENT | 15A | 18A |
Example configurations for 450Wp and 550Wp PV modules are provided in the manual, detailing series connections for different inverter models and total power output.
PV Module Cable Connection:
- Strip 10 mm insulation from the positive and negative cables.
- Check the polarity of the connection cable from the PV modules and the PV input connectors. Connect the positive (+) cable to the positive (+) PV input connector and the negative (-) cable to the negative (-) PV input connector.
- Ensure the wires are correctly connected.
VI. Final Assembly
After connecting all wires, replace the bottom cover and secure it with two screws.
Operation
I. Power ON/OFF
After correct installation and battery connection, press the power switch to turn the unit on.
II. Operation and Display Panel
The operation and display panel on the front of the inverter includes three LED indicators, four function buttons, and an LCD display showing operational status, power information, and battery status.
| LED Indicator | Message | ||
| AC/INV | Green | Solid | Output is powered by mains (Line Mode). |
| Flashing | Output is powered by battery or PV in Battery Mode. | ||
| CHG | Green | Solid | Battery is charged. |
| Flashing | Battery is charging. | ||
| FAULT | Red | Solid | Inverter has a fault. |
| Flashing | Inverter has a warning. |
Key Functions
| Key | Description |
| ESC | Exit setting mode. |
| UP | Navigate to the previous setting. |
| DOWN | Navigate to the next option. |
| ENTER | Confirm selection in setting mode or enter setting mode. |
III. LCD Display Settings
The manual details various programmable settings (01-47) for the inverter, including:
- Program 01: Output Source Priority (Utility First, Solar First, SBU Priority, SUB Priority, SUF Priority)
- Program 02: Max Charging Current (Configures total charging current for solar and mains chargers)
- Program 03: AC Input Voltage Range (Appliance, UPS, Generator settings)
- Program 05: Battery Type (AGM, Flooded, User Defined, Lithium Battery without communication)
- Program 06 & 07: Automatic Restart (After overload or over-temperature)
- Program 08: Output Voltage (220V, 230V, 240V)
- Program 09: Output Frequency (50Hz, 60Hz)
- Program 10: Auto Bypass (Manual, Auto)
- Program 11: Max AC Charging Current
- Program 12: AC Source Voltage Setting Point (for SBU/Solar First priority)
- Program 13: Battery Mode Voltage Setting Point
- Program 16: Charging Source Priority (Solar, Solar & Mains, Solar Only)
- Program 18: Buzzer Mode (Off, Warning/Fault, Fault)
- Program 19: Auto Return to Default Display Screen
- Program 20: Backlight Control
- Program 23: Overload Bypass
- Program 25: Modbus ID Setting
- Program 26: Float Charging Voltage (C.V. Voltage)
- Program 27: Holding Charging Voltage
- Program 29: Low DC Shut-off Voltage
- Program 32: Float Charging Time (C.V. Stage)
- Program 33: Battery Equalization
- Program 34: Battery Equalizing Voltage
- Program 35: Battery Equalizing Time
- Program 36: Battery Conditioning Time
- Program 37: Equalizing Interval
- Program 39: Equalizing Activation (Enable, Disable)
- Program 41: Auto Activation for Lithium Battery
- Program 42: Manual Activation of Lithium Battery
- Program 46: Max Discharge Current Protection
Battery Equalization
The charge controller includes an equalization function to mitigate negative chemical effects like stratification and sulfate crystal formation, which can reduce battery capacity. Regular equalization is recommended.
How to Use Equalization:
- Enable the battery equalization function in the LCD monitor settings (Program 33).
- Apply the function either by setting the equalization interval in Program 37 or by activating it immediately in Program 39.
When to Equalize:
The unit enters equalization mode when the set time is reached or when equalization is activated immediately during the maintenance mode.
Equalization Charging Time and Timeout:
During equalization, the controller provides maximum charging power until the battery voltage reaches the set equalization voltage. It then uses constant voltage charging. The battery remains in equalization until the set equalization time is met. If the voltage does not reach the set level within the time, the equalization time is extended. If the voltage is still below the set level after the extended time, the controller exits equalization and returns to maintenance mode.
V. Lithium Battery Settings
Settings for Lithium Battery Without Communication
This section provides recommendations for using lithium batteries to prevent BMS protection activation when communication is absent. Follow these steps:
- Determine the battery BMS specifications: Maximum charging voltage, maximum charging current, and discharge cut-off voltage.
- Set the battery type to 'LIB' (Program 05).
- Set the C.V. (bulk charging voltage) to the BMS maximum charging voltage minus 0.5V.
- Set the float charging voltage to the same value as the C.V. voltage.
- Set the low DC shut-off voltage to at least the BMS discharge cut-off voltage plus 2V.
- Set the maximum charging rate to be lower than the BMS maximum charging rate.
- Set the return-to-source voltage point (Program 12) to be greater than or equal to the low DC shut-off voltage plus 1V.
Notes:
- It is best to complete settings with the inverter off (LCD display showing information only).
- Restart the inverter after completing the settings.
Error Codes
| Error Code | Description | Icon |
| 01 | Inverter module overheat | |
| 02 | DCDC module overheat | Icon with error number |
| 03 | Battery voltage too high | |
| 04 | PV module overheat | |
| 05 | Output short circuit | |
| 06 | Output voltage too high | |
| 07 | Overload - shutdown time | |
| 08 | Bus voltage too high | |
| 09 | Bus soft start failure | |
| 10 | PV current overload | |
| 11 | PV overvoltage | |
| 12 | DCDC current overload | |
| 13 | Current overload or overvoltage | |
| 14 | Bus voltage too low | |
| 15 | Inverter failure | |
| 18 | OP offset current too high | |
| 19 | Inverter offset current too high | |
| 20 | DC/DC offset current too high | |
| 21 | PV offset current too high | |
| 22 | Output voltage too low | |
| 23 | Inverter negative power |
Warning Indicator
| Code | Message | Alarm | Display Icon |
| 02 | Too high temperature | Three beeps every second | Icon |
| 04 | Battery discharged | One beep every second | Icon |
| 07 | Overload | Beeps every 0.5 seconds | Icon |
| 10 | Power reduction | Two beeps every 3 seconds | Icon |
| 14 | Fan blocked | None | Icon |
| 15 | Low PV energy | Two beeps every 3 seconds | Icon |
| 19 | Lithium battery communication failure | Beeps every 0.5 seconds | Icon |
| 21 | Lithium battery output current too high | None | Icon |
| E9 | Battery equalization | None | Icon |
| bP | Battery not connected | None | Icon |
Specifications
Table 1: Line Mode Specifications
| Inverter Model | 1.5 KVA | 1.5KVA | 2.5KVA | 3.5KVA | 5.5KVA |
| Input Voltage Waveform | Sine wave (mains or generator) | ||||
| Nominal Input Voltage | 230V AC | ||||
| Low loss voltage | 170V AC ± 7V (UPS) / 90V AC ± 7V (Appliance) | ||||
| Low loss voltage return | 180V AC ± 7V (UPS) / 100V AC ± 7V (Appliance) | ||||
| High loss voltage | 280V AC ± 7V | ||||
| High loss voltage return | 270V AC ± 7V | ||||
| Max. Input AC Voltage | 300V AC | ||||
| Nominal Input Frequency | 50Hz / 60Hz (Auto detection) | ||||
| Low loss frequency | 40 ± 1 Hz | ||||
| Low loss frequency return | 42 ± 1 Hz | ||||
| High loss frequency | 65 ± 1 Hz | ||||
| High loss frequency return | 63 ± 1 Hz | ||||
| Output short circuit protection | Battery Mode: Electronic circuits | ||||
| Efficiency (Line mode) | >95% (at rated R load, battery fully charged) | ||||
| Switching time | 10ms typical (UPS) / 20ms typical (Appliance) | ||||
| Output Power Limitation: Output power is limited when input AC voltage drops to 95V or 170V, depending on the model. | Diagram showing output power vs. input voltage curve. | ||||
Table 2: Inverter Mode Specifications
| Inverter Model | 1.5 KVA | 1.5KVA | 2.5KVA | 3.5KVA | 5.5KVA |
| Rated Output Power | 1.5KVA/1.5KW | 2.5KVA/2.5KW | 3.5KVA/3.5KW | 5.5KVA/5.5KW | |
| Output Voltage Waveform | Pure Sine Wave | ||||
| Output Voltage Regulation | 230Vac ± 5% | ||||
| Output Frequency | 50Hz or 60Hz | ||||
| Max. Efficiency | 94% | ||||
| Peak Power | Max. power: 2* rated power for 5 seconds | ||||
| Nominal DC Input Voltage | 12 Vdc | 24 Vdc | 48 Vdc | ||
| Cold Start Voltage | 11.0 Vdc | 23.0 Vdc | 46.0 Vdc | ||
| DC Low Voltage Warning (AGM/Flooded) | @ Load < 20%: 11.0Vdc @ 20%≤ Load < 50%: 10.7Vdc @ Load ≥ 50%: 10.1Vdc |
@ Load < 20%: 22.0Vdc @ 20%≤ Load < 50%: 21.4Vdc @ Load ≥ 50%: 20.2Vdc |
@ Load < 20%: 40.4Vdc @ 20%≤ Load < 50%: 42.8Vdc @ Load ≥ 50%: 44.0Vdc |
||
| DC Low Voltage Warning Return (AGM/Flooded) | @ Load < 20%: 11.5Vdc @ 20%≤ Load < 50%: 11.2Vdc @ Load ≥ 50%: 10.6Vdc |
@ Load < 20%: 23.0Vdc @ 20%≤ Load < 50%: 22.4Vdc @ Load ≥ 50%: 21.2Vdc |
@ Load < 20%: 42.4Vdc @ 20%≤ Load < 50%: 44.8Vdc @ Load ≥ 50%: 46.0Vdc |
||
| DC Low Shut-off Voltage (AGM/Flooded) | @ Load < 20%: 10.5Vdc @ 20%≤ Load < 50%: 10.2Vdc @ Load ≥ 50%: 9.6Vdc |
@ Load < 20%: 21.0Vdc @ 20%≤ Load < 50%: 20.4Vdc @ Load ≥ 50%: 19.2Vdc |
@ Load < 20%: 42.0Vdc @ 20%≤ Load < 50%: 40.8Vdc @ Load ≥ 50%: 38.4Vdc |
||
Table 3: Charging Mode Specifications
| Utility Charging Mode | ||||||
| Model | 1.5KVA | 1.5KVA | 2.5KVA | 3.5KVA | 5.5KVA | |
| Max. Charging Current (PV+AC) (@ VI/P=230Vac) | 100Amp | 60Amp | 100Amp | 100Amp | 100Amp | |
| Max. Charging Current (AC) (@ VI/P=230Vac) | 60Amp | |||||
| Bulk Charging Voltage | Flooded: 14.6Vdc AGM/GEL: 14.1Vdc |
Flooded: 29.2VDC AGM/GEL: 28.2 VDC |
Flooded: 58.4 VDC AGM/GEL: 56.4 VDC |
|||
| Float Charging Voltage | 13.5Vdc | 27VDC | 54VDC | |||
| Overcharge Protection | 16.5Vdc | 32VDC | 63VDC | |||
| Charging Algorithm | Three-stage | |||||
| Charging Curve | Diagram showing charging curve stages (Bulk, Absorption, Float) | |||||
| Solar Input | ||||||
| Model | 1.5 KVA | 1.5KVA | 2.5KVA | 3.5KVA | 5.5KVA | |
| Rated Power | 2000W | 2000W | 3000W | 4000W | 5500W | |
| Max. PV Array Open Circuit Voltage | 500Vdc | |||||
| PV Array MPPT Voltage Range | 30Vdc 500 Vdc | 60Vdc 500 Vdc | ||||
| Max. Input Current | 15A | 15A | 15A | 15A | 18A | |
| Max. PV Charging Current | 100A | 60A | 100A | 100A | 100A | |
Table 4: Operating Conditions
| Model | 1.5 KVA | 2.5KVA | 3.5KVA | 5.5KVA |
| Operating Temperature Range | −10°C to 55°C | |||
| Storage Temperature | −15°C to 60°C | |||
| Humidity | 5% to 95% (Non-condensing) | |||
Troubleshooting
| Problem | LCD/LED/Buzzer | Possible Cause | Solution |
| Unit automatically shuts down during startup process. | LCD/LED display and buzzer active for 3 seconds, then completely off. | Battery voltage too low. | Charge the battery. Replace the battery. |
| No response after turning on the unit. | Not working | Battery voltage too low. Battery polarity reversed. |
Check battery and wiring connections. Charge the battery. Replace the battery. |
| Power is available, but the unit operates in battery mode. | LCD displays input voltage as 0 and green LED flashes. | Overcurrent or input voltage protection activated. | Ensure AC switch is off and AC line is correctly wired. |
| Green LED flashes. | Poor AC power quality (mains or generator). | Check if the AC line is too thin and/or too long. Verify generator operation or input voltage range setting (UPS Appliance). | |
| Green LED flashes. | Output source priority set to "Solar First". | Change output source priority to "Utility first". | |
| Internal relay repeatedly turns on and off when unit is powered on. | LCD display and LEDs flash. | Battery is disconnected. | Check battery cable connections. |
| Continuously beeping and red LED is on. | Error code 07 | Overload fault. Inverter overloaded by 110% and timeout. | Reduce load by turning off some appliances. |
| Error code 05 | Output short circuit. | Check wiring and remove abnormal load. | |
| Error code 02 | Internal temperature of inverter components exceeds 100°C. | Ensure airflow to the unit is not blocked and ambient temperature is not too high. | |
| Error code 03 | Battery overcharged. Battery voltage too high. |
Contact service center. Check if battery specifications and quantity meet requirements. |
|
| Error code 06/22 | Invalid output (inverter voltage lower than 190 Vac or higher than 260 Vac). | Reduce load. Contact service center. | |
| Error code 08/09/15 | Internal component failure. | Contact service center. | |
| Error code 13 | Current overload or overvoltage. | Restart the unit. If the error persists, contact service center. | |
| Error code 14 | Bus voltage too low. | ||
| Other error code | If cables are correctly connected, contact service center. |
Maintenance
- Keep the inverter clean using a soft, dry cloth. Do not use chemical agents.
- Regularly inspect power cables and connectors for damage (fraying, cracking, looseness).
- Ensure ventilation openings are clear and unobstructed for adequate cooling.
- Avoid contact with water or other liquids to prevent electrical damage.
Disposal
This product is subject to the Waste Electrical and Electronic Equipment (WEEE) regulations. Dispose of it at an e-waste collection point that ensures safe recycling in accordance with GPSR standards. Contact the manufacturer or an authorized service center for disposal inquiries.
Warranty and Service Information
The product is covered by a 24-month manufacturer's warranty from the date of purchase, covering material and workmanship defects. For any issues, contact the service department for prompt and professional assistance. The warranty does not cover damage from misuse, drops, mechanical damage, unauthorized repairs, or attempted disassembly.
