Hybrid solar systems generate electricity and work in the same manner as conventional grid-tied solar systems, but they have a specifically designed hybrid inverter with additional battery storage. The additional backup power can be utilized later in case of power shutdown. Thus, hybrid solar systems provide continuous power even if grid power is not available.
Just like off-grid or on-grid solar systems, sometimes hybrid solar systems may get into problems and won’t work properly. Most of the problems with hybrid solar systems can be resolved easily. This article will provide you with troubleshooting tips and techniques to fix hybrid solar systems that are not working properly.
Common Problems & Their Troubleshooting in Hybrid Solar System
The hybrid solar system contains multiple components such as solar hybrid inverters, controllers, solar panels, batteries, cables, switches, and other equipment. Problems can arise anywhere in the system which can be easily fixed. Below we have compiled some common problems with their troubleshooting solutions that can occur in a hybrid solar system:
1. The Inverter LCD Screen Has No Display
When the hybrid solar inverter screen has no display then the possible reasons with solutions are given below:
Possible Reason
1) The battery voltage is not enough. If the battery is not used for a long time then it will self-discharge and doesn’t retain the charge to power the inverter. The hybrid solar inverters can support a DC bus voltage of 12V, 24V, 48V, 96V, and so on.
2) The battery terminals are reversely connected.
3) The Inverter has a fault.
Solution
1. Check the DC bus voltage with a multimeter, if it is below the required, then recharge the battery either through solar panels or any other DC power source. If there is no power, then either the battery is faulty or the cable is damaged. Replace the faulty battery and damaged cable with a new one.
2. If the battery terminals are reversed, rewire them. The battery has positive and negative terminals. The red wire should be connected to the positive terminal and the black with to the negative terminal.
3. Turn On the DC switch, its LCD will turn On. If it’s still not turning On then the inverter is faulty. Contact your solar installer for technical assistance.
2. The Battery is Not Charging
The battery is either charged with the PV solar panels and controller or through the mains AC supply and controller. If the battery is not charging then below are the possible reasons and their solutions:
Possible Reason
1. The main power and DC power switches may be Off.
2. AC supply and PV solar panels voltages are not fulfilled.
3. The battery is already fully charged.
Solution
1. Check the main power and DC power switches. Both should be in the On position.
2. Check the AC mains voltage and PV module bus voltage. It should be greater than the battery voltage to charge it. Then check the cable and circuitry for any damage. Replace any cable if found damaged.
3. If the battery is fully charged then to protect the battery, the circuit will not charge it further. For example, a 12V battery in a fully charged state has a voltage between 12.8~13.5V.
4. If the battery is still not charging and its voltage is below 10V then it should be replaced with a new one.
3. The Inverter is Overloaded
If the hybrid solar inverter is overloaded then it will shut down and won’t start to protect its circuitry and battery. Below are the possible reasons with solutions for this fault:
Possible Reason
1. If the load running on the hybrid solar inverter exceeds the mentioned rating on the inverter then it will first alarm and shut down if the load exceeds more.
2. For example, if you put a 5.5 kW load on a 5 kW hybrid solar inverter, then it will go into overload condition and eventually shut down to protect the battery and inverter.
3. If the inductive load running takes a high in-rush current in the startup, the hybrid solar inverter will go into an overload condition.
Solution
1. Put off any extra load on the hybrid solar system.
2. It is recommended that the load shall not exceed 80% of the capacity of the inverter’s rating.
3. For example a 5kW hybrid solar inverter, the load shall not exceed 4kW to protect the inverter and battery.
1. For any inductive or motorized load, ensure that the maximum load with startup in-rush current shall not exceed the 80% capacity of an inverter.
4. Earth Leakage Current Error
The hybrid solar inverter can give the earth leakage current error and its ground fault circuit interrupter (GFCI) breaker trips if the earth leakage current exceeds the maximum allowable given rating. The following are the possible reasons for the given solutions:
Possible Reason
1. If the ground voltage is too high causing any leakage of current in the earth wiring.
2. Proper earthing has not been done by the installer.
3. The GFCI breaker trips to protect hybrid solar inverters.
Solution
1. Isolate the solar hybrid inverter by disconnecting the AC, DC & GFCI circuit breakers.
2. Check the grounding circuit wiring and GFCI breaker, it should be properly implemented as per instructions given in the manual.
3. Replace the earth cables and GFCI breaker if found faulty.
4. Connect the hybrid solar inverter by turning on the first the DC breaker, then the AC breaker, and finally the GFCI breaker. The system will now turn On.
5. The Fan Fault
The hybrid solar inverter can give a fan fault on the LCD screen and alarms if the fans installed within the inverter fails to work. Following given are the possible causes with a solution of a fan fault:
Possible Reason
1. The hybrid solar inverter is overheating and the fans aren’t able to cool them down.
2. Dust and debris accumulation on the fans.
3. One of the fans has become faulty.
Solution
1. Check if all fans are running Ok.
2. Shut down the solar hybrid inverter and restart it.
3. If any fan is not running, then replace it with the same part number.
4. If the fan fault remains, check the temperature of the inverter, if it overheats then cool it down by mounting it in a ventilated environment.
Also, remove any dust or debris by air blower after a long time usage of solar hybrid inverter.
Conclusion
Hybrid solar system manufacturers are now offering solutions with 5 years or more warranty on different components with only solar panels having 25 years of warranty. Hybrid solar systems are generating renewable electricity with more reliability and efficiency than in the past. However, sometimes the hybrid solar systems won’t work properly and need troubleshooting.
This article has outlined all the possible common problems with simple troubleshooting solutions that can be implemented by the user itself. However, if the problem persists, then contact your hybrid solar system manufacturer at their helpline to get technical support. Moreover, always follows all the safety precautions given in the user manual before doing any troubleshooting task.
