Solar Inverter Repairs and Solutions for Every Customer
According to the U.S. Department of Energy. the industry standard for solar photovoltaic (PV) panel warranties is 20 years, while most inverters only ship with 10 years of warranty protection. This means you’ll almost certainly need to pay for solar inverter repair at least once over your PV system’s lifetime.
Inverter servicing is a cost that catches many solar customers off-guard. And it can extend the original payback period – while lowering the expected return on investment (ROI).
Use this guide to navigate the solar power inverter repair landscape so that your own clean energy investment delivers more predictable returns.
There are no industry standards for preventive maintenance frequency. However, regular servicing allows you to catch and correct problems early on, which is why you should always have a maintenance roadmap in place.
All You Need to Know About Repairing Solar Inverters
PV panels generate direct current (DC) electricity, but most consumer appliances use alternating current (AC). Solar inverters are responsible for converting this power so you can harness the free energy hitting your roof.
When an inverter fails, your solar panels still produce electricity. But none of the energy generated is usable.
How Often do I Need to Repair my Solar Inverter?
Every PV installation is unique; thus, there is no universal timetable for solar inverter servicing.
Fault Finding Solar PV System. Electrician Life
- Solar panels are normally covered for 20 to 25 years
- Inverters come with 10 to 25 years (depending on the technology)
Problems with expensive solar system
- Battery storage solutions typically ship with 5 or 10 years
Failures and malfunctions are inevitable which means you should budget at least one replacement or repair into the total lifetime budget of your investment.
But don’t service costs fall under normal solar inverter warranties? Not necessarily.
Extremely High Battery Voltage
High battery voltage readings indicate that there is some issue with the controller. You can check by disconnecting the lead battery from the positive terminal and keeping the PV array disconnected. Once you do this, the charging light on the controller should not light up. Now go to the solar panel terminal and measure the voltage from the charge controller. If you see a green light on the inverter, it indicates that the controller is damaged.
There are several reasons because of why a battery might fail to charge a solar inverter, including
To rectify these problems, you need to check if the battery terminals of the inverter have corrosion and clean them. However, if the battery is dead, you have no other option but to replace the battery.
Solar inverters contain several electrical components and are thus quite sensitive to high temperatures. The resulting heat can result in a huge cut in production. In fact, they can even cease production if the temperature reaches the maximum limit. Thus, you need to check in the initial design stages if the suggested cooling technology is sufficient and if it has adequate capacity. For instance, it is extremely important that the building where the inverter is placed and the switch cabinet is properly ventilated.
Apart from performing an evaluation of the design, we strongly advise you to check the cooling while the inverter is working regularly and determine if the ventilation or cooling system is working optimally. Additionally, you can take some steps to prevent temperatures from soaring. For instance, you can install and clean dust filters, remove undergrowth that hampers airflow, etc.
Another reason why a solar power inverter fails to function optimally is because of the isolation fault. The isolation fault happens due to a short circuit between numerous parts of the circuit, and the solar inverter is then going to signal an isolation alarm. Typically, the short circuit is a result of poor installation, moisture in the connection part of the photovoltaic module, an improper connection of the direct current cables to the panel, or a combination of moisture and damage to the sleeve on the cabling. This will be a fairly common problem in areas that are in close proximity to the sea or experience high levels of humidity.
In case of an isolation problem, the solar inverter is going to cease working entirely or continue to operate at the minimum isolation level needed. This can result in the loss of production. Thus, it’s important to make sure that the DC cables used are of high quality and installed properly. To stop this problem from occurring, it’s also important that you choose the right level of protection for the inverter building and the inverter cabinet.
Safety Alert! An isolation fault can lead to potentially lethal voltages in the conducting parts of the system. Make sure that maintenance is always performed according to the relevant safety standards.
Solar Integration: Inverters and Grid Services Basics
An inverter is one of the most important pieces of equipment in a solar energy system. It’s a device that converts direct current (DC) electricity, which is what a solar panel generates, to alternating current (AC) electricity, which the electrical grid uses. In DC, electricity is maintained at constant voltage in one direction. In AC, electricity flows in both directions in the circuit as the voltage changes from positive to negative. Inverters are just one example of a class of devices called power electronics that regulate the flow of electrical power.
Fundamentally, an inverter accomplishes the DC-to-AC conversion by switching the direction of a DC input back and forth very rapidly. As a result, a DC input becomes an AC output. In addition, filters and other electronics can be used to produce a voltage that varies as a clean, repeating sine wave that can be injected into the power grid. The sine wave is a shape or pattern the voltage makes over time, and it’s the pattern of power that the grid can use without damaging electrical equipment, which is built to operate at certain frequencies and voltages.
The first inverters were created in the 19th century and were mechanical. A spinning motor, for example, would be used to continually change whether the DC source was connected forward or backward. Today we make electrical switches out of transistors, solid-state devices with no moving parts. Transistors are made of semiconductor materials like silicon or gallium arsenide. They control the flow of electricity in response to outside electrical signals.
A 1909 500-kilowatt Westinghouse “rotary converter,” an early type of inverter. Illustration courtesy of Wikimedia.
If you have a household solar system, your inverter probably performs several functions. In addition to converting your solar energy into AC power, it can monitor the system and provide a portal for communication with computer networks. Solar-plus–battery storage systems rely on advanced inverters to operate without any support from the grid in case of outages, if they are designed to do so.
Toward an Inverter-Based Grid
Historically, electrical power has been predominantly generated by burning a fuel and creating steam, which then spins a turbine generator, which creates electricity. The motion of these generators produces AC power as the device rotates, which also sets the frequency, or the number of times the sine wave repeats. Power frequency is an important indicator for monitoring the health of the electrical grid. For instance, if there is too much load—too many devices consuming energy—then energy is removed from the grid faster than it can be supplied. As a result, the turbines will slow down and the AC frequency will decrease. Because the turbines are massive spinning objects, they resist changes in the frequency just as all objects resist changes in their motion, a property known as inertia.
As more solar systems are added to the grid, more inverters are being connected to the grid than ever before. Inverter-based generation can produce energy at any frequency and does not have the same inertial properties as steam-based generation, because there is no turbine involved. As a result, transitioning to an electrical grid with more inverters requires building smarter inverters that can respond to changes in frequency and other disruptions that occur during grid operations, and help stabilize the grid against those disruptions.
Grid Services and Inverters
Grid operators manage electricity supply and demand on the electric system by providing a range of grid services. Grid services are activities grid operators perform to maintain system-wide balance and manage electricity transmission better.
When the grid stops behaving as expected, like when there are deviations in voltage or frequency, Smart inverters can respond in various ways. In general, the standard for small inverters, such as those attached to a household solar system, is to remain on during or “ride through” small disruptions in voltage or frequency, and if the disruption lasts for a long time or is larger than normal, they will disconnect themselves from the grid and shut down. Frequency response is especially important because a drop in frequency is associated with generation being knocked offline unexpectedly. In response to a change in frequency, inverters are configured to change their power output to restore the standard frequency. Inverter-based resources might also respond to signals from an operator to change their power output as other supply and demand on the electrical system fluctuates, a grid service known as automatic generation control. In order to provide grid services, inverters need to have sources of power that they can control. This could be either generation, such as a solar panel that is currently producing electricity, or storage, like a battery system that can be used to provide power that was previously stored.
Another grid service that some advanced inverters can supply is grid-forming. Grid-forming inverters can start up a grid if it goes down—a process known as black start. Traditional “grid-following” inverters require an outside signal from the electrical grid to determine when the switching will occur in order to produce a sine wave that can be injected into the power grid. In these systems, the power from the grid provides a signal that the inverter tries to match. advanced grid-forming inverters can generate the signal themselves. For instance, a network of small solar panels might designate one of its inverters to operate in grid-forming mode while the rest follow its lead, like dance partners, forming a stable grid without any turbine-based generation.
Reactive power is one of the most important grid services inverters can provide. On the grid, voltage— the force that pushes electric charge—is always switching back and forth, and so is the current—the movement of the electric charge. Electrical power is maximized when voltage and current are synchronized. However, there may be times when the voltage and current have delays between their two alternating patterns like when a motor is running. If they are out of sync, some of the power flowing through the circuit cannot be absorbed by connected devices, resulting in a loss of efficiency. total power will be needed to create the same amount of “real” power—the power the loads can absorb. To counteract this, utilities supply reactive power, which brings the voltage and current back in sync and makes the electricity easier to consume. This reactive power is not used itself, but rather makes other power useful. Modern inverters can both provide and absorb reactive power to help grids balance this important resource. In addition, because reactive power is difficult to transport long distances, distributed energy resources like rooftop solar are especially useful sources of reactive power.
A worker checks an inverter at the 2MW CoServ Solar Station in Krugerville, Texas. Photo by Ken Oltmann/CoServ.
Types of Inverters
There are several types of inverters that might be installed as part of a solar system. In a large-scale utility plant or mid-scale community solar project, every solar panel might be attached to a single central inverter. String inverters connect a set of panels—a string—to one inverter. That inverter converts the power produced by the entire string to AC. Although cost-effective, this setup results in reduced power production on the string if any individual panel experiences issues, such as shading. Microinverters are smaller inverters placed on every panel. With a microinverter, shading or damage to one panel will not affect the power that can be drawn from the others, but microinverters can be more expensive. Both types of inverters might be assisted by a system that controls how the solar system interacts with attached battery storage. Solar can charge the battery directly over DC or after a conversion to AC.
Learn more about the solar office’s systems integration program.
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Can I Repair My Solar Inverter Myself?
No. You should never try to fix an inverter yourself. It is a complicated piece of technology that requires a lot of technical knowledge, and you could end up making the problem worse, or hurting yourself if you try to fix it.
Along with making the issue worse or injuring yourself, attempting to fix the inverter on your own could void the maintenance and service agreement for your entire solar system. In addition, you could face repercussions from your utility company and other government entities because you aren’t a licensed solar technician.
Ultimately, if you notice that something seems off with your inverter, it is best to call in the professionals. They should be able to easily determine the problem, and either fix or replace the inverter as needed.
Can I Hire Someone To Monitor My Solar Inverter?
Your solar installer may offer a professional monitoring solution, or you can purchase one from another solar company like Palmetto. Our Palmetto Protect service is available to any homeowner with a solar power system, whether we installed it or not.
With 24/7 proactive professional monitoring, you can enjoy real-time energy monitoring, one-click customer support, comprehensive energy recommendations, and best-in-class service and solar panel repair, so your system can run at peak efficiency.
Guide To Solar Inverter Maintenance, Repair, and Service
Solar panel care and solar inverter care are intertwined. You can’t take care of your solar power system properly if you aren’t caring for your solar inverter. That’s why solar inverter maintenance, solar inverter service, and solar inverter repair are so important.
Without a fully functioning inverter, the DC electricity created by your solar panels can’t become the AC electricity your home needs. Your inverter must be working properly for your system as a whole to work efficiently.
If your inverter does stop working, you need to contact a licensed solar professional to diagnose the issue and provide a solution. This could be the company that installed it, the manufacturer of the inverter, or a trusted local solar company like Palmetto.
To protect yourself before your solar inverter even needs maintenance, repair, or service, talk to Palmetto today to learn about our Palmetto Protect monitoring service and solar inverter maintenance package.