March 23, 2024

Manual vs Automatic Solar Tabber and Stringers: The Differences

The industry of solar energy is flourishing, and that requires the development of highly efficient and reliable methods for assembling solar panels. The two key subsystems in this process are solar panel machines are tabbers and stringers. These devices bring together solar cells electrically in series and parallel circuits, respectively, to form a solar PV module. The tabbing and stringing process is one of the key steps that are directly responsible for the enhanced efficiency and performance of the solar panel. The results of the manufacturing process may be incomplete or wrong if it causes losses in power, shortens solar panels life, and compromises their reliability. However, the decision between using manual and automatic tabbers and stringers is even more critical to make.

In this article, a comparison of main features of manual and automatic tabber and stringer systems with respect of various factors such as production speed, cost and efficiency analysis, and automation level is deliberated and aid in making the right choice for your solar panel production needs.

Solar Tabber and Stringers

Before we get into the comprehensive details of manual and automatic systems, it is essential that we understand the basics of tabbers and stringers and their roles. The main function of the Tabber and Stringer is to make cell strings, interconnection electrically the PV cells with ribbon. Quality of both, cells and strings are checked during the process.
• Solar Tabber: In this machine, conductive strips, which are referred to as tabs, are attached to the positive and negative poles of each solar cell. This is where a tab connection in a serial circuit takes place.
• Solar Stringer: The stringer connects in a series all the tabbed solar cells with a string. It connects the tabs to each other to form a unified path.

Manual vs. Automatic Tabber and Stringer Systems

Manual Tabber and Stringer

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It is based on the manual proficiency of experienced workers, who perform each operation by hand (manually). A manual process gives the option of selection and customization. The uniqueness of manual tabbing and stringing is the possibility of processing specific or custom solar cell layouts. The capabilities of skilled technicians is mandatory to adjust the cell size, shapes and materials of different levels make the manual processes applicable to prototypes and small-scale production runs.

Automatic Solar Tabber and Stringer

For the solar industry, the shift to automation has been outstanding with the emergence of new tabbing and stringing equipment. These robots rely on robotics, computer vision, and precision mechanics to automate the whole process, which gives much more advantages than manual methods.

The main differences between manual and automatic Tabber and Stringers are as follows:

1. Automation Level

The biggest difference is the degree of automation. Manual systems involve people doing most of the work, while automatic systems largely operate themselves.

Manual tabber and stringers: An operator introduces each cell separately into the tabber, aligns them for tab attachment, and then hits the tabbing button. In the stringer, the operator, in turn, tabs the cell string, and then using the soldering/ welding process, the task is initiated. This kind of process is very labor intensive and can have human errors.

• Automatic tabber and stringers: Automatic tabbers and stringers considerably reduce human participation. The solar cells are pulled into a feeder system and the machine takes the lead. It automatically tabs, positions, and welds/solders the cells to form an entire string. Thus, human error is avoided and the quality is standardized. Automatic machine has high speed dual track tabber stringer, with camera for ribbon alignment and broken cell detection, the robot carries the solar cells more quickly and stable.

2. Production Speed

Production speed is directly related to the amount of solar panels that a system can generate during a certain time.

Manual tabber and stringers: In fact, the automation of manual systems results in a significant reduction in throughput. The speed is controlled by the operator's hand movement and the number of operators.

• Automatic tabber and stringers: Automated process systems have much faster throughput rates compared to manual systems. They can process cells a lot faster and can work continuously with no interruptions which makes them more productive. High speed Tabber & Stringer with capacity of up to 1300 - 5000 cells/hour.

3. Cost and Efficiency Analysis

Cost and efficiency factors, which are central to the decision-making process, are to be considered while thinking about manual or automatic tabbing and stringing processes in solar panel manufacturing. • Manual tabber and stringers: Manual tabber and stringers often have lower investment expenses since no equipment and infrastructure are necessary at the beginning. Nevertheless, the manual processes come at a price that involves labor costs, mostly in regions with higher labor rates and for large-volume productions. The use of human operators involves not only labor costs but also costs entailing salaries, training, and benefits.

• Automatic tabber and stringers: Automatic tabbing and stringing processing lines generate a notable capital expenditure for the machinery, installation, and integration into the production line. On the downside, these initial costs can be counterbalanced by the long-term advantages of having higher throughput, lower labor costs, and better efficiency.

4. Labor Cost

Manual systems are costlier to operate as they involve more employees, and hence the labor costs are high.

• Manual tabber and stringers: This dependence on human operators accounts for a lot of labor costs, which include wages, training, and benefits.

• Automatic tabber and stringers: Automation systems, in turn, need fewer operators, and cut overall labor costs. The automation technology may have initial investment costs but the future labor cost will be far lower.

5. Accuracy and Consistency

Maintaining the same rate of quality and precision in assembling solar panels is a must. To maintain quality, manual, and automatic systems both use several quality control measures, for example, visual inspection, electrical testing, and Statistical Process Control (SPC) techniques. Nevertheless, it is commonly known that the automation process usually has in-line quality control and real-time correction which help in the reduction of defects and therefore improve the overall quality.

• Manual tabber and stringers: Manual processes imply more human error and inconsistency in column placement, cell sizing, and stringing. This leads to errors. These discrepancies may affect the effectiveness of the solar panel in terms of efficiency and performance, causing potential power losses or hot spots.

• Automatic tabber and stringers: The different approach on the other side is that automatic machines have been made to maintain the perfect tolerance and guarantee that the tabs are always in a precise and repeatable position on the string. Consistency in this case is the crucial part that vastly maximizes the power output and reliability of solar panels, especially in large projects of utilities where small deviations can result in huge losses during its lifespan.

6 Floor Space Requirements

Running each system may have a divergent shape of the physical footprint.

• Manual tabber and stringers: Manual systems, unlike automation, normally take less space to be installed since individual operators maintain their workstations.

• Automatic tabber and stringers: These machines consume more energy than manual systems because they are equipped with an additional set of machinery that is used in the delivery and feeding. On the other hand, their high processing can remain as a way to counter the space demand.

7. System Cost

Each system type varies the initial capital cost.

• Manual tabber and stringers: The investment costs for manual systems is lower than automatic systems in the initial stage, but automation systems become more appealing in the long run due to lower operational costs and higher levels of production.

• Automatic tabber and stringers: The cost of automatic systems is higher than that of manual ones due to the intricate machinery and embellishment of automation involved in the process. Nevertheless, the spatial relevancy could be higher since this form of automation takes more period to reach the efficiency of cost.


Manual Stringer

Automatic Stringer

Automation Level

Manual operation


Production Speed



Labor Cost



Accuracy & Consistency

Lower, Prone to human error

Higher, Consistent

Floor Space Requirement



Maintenance Needs

Less complex (tools and soldering equipment)

More complex (automated machinery)

System Cost

Lower initial cost

Higher initial cost

Ideal for Production Volume



Scalability for Future Growth



Deciding Between Manual and Automatic Solar Tabber and Stringers

The best option between manual and automatic tabber and stringer systems depends on many variables related to your solar panel assembly business.
1. Skill Level and Training
  • Skilled Workforce: If you have a labor force prepared for the skill set demands of manual soldering and cell handling, a manual mode could be worked with. On the other side, this must be considered in the budgeting; the training costs and the attitude of operators must be kept at a decent level.
  • Limited Skilled Workforce: In case human skills are indispensable, those systems are still beneficial. They include a minimum domestic level of education, requiring operator training which involves systems operation and monitoring, thus machine soldering skills are not needed.
2. Budget Considerations
  • Limited Budget: Cost can be a paramount factor for a manual system as it appears cheaper with the initial price when the long-term cost is considered.
  • Investment for Growth: If you are planning for future expansion and more productions with higher volume, an automatic system may be considered an investment in an early stage. The efficiency and quality of the system can be doubled in the long term, which is more than sufficient to make up for the larger initial investment.
3. Future Scalability
  • Limited Growth Plans: In these situations, if you want to start with a system that is manual a temporary solution might be helpful.
  • Growth Potential: When you expect to see growth in the next few years, an automatic system will be the best bet as it will be easier to expand it. Its capability to handle a boost in production in an undisturbed way is precisely why this proves to be a good investment.
  • Technological Advancements: With the growing talent in the technology space, the already existing automatic tabber and stringer systems have come up with additional new features to enhance production efficiency.
4. Additional Considerations
  • Return on Investment (ROI): Strategically assess the ROI for accounts payable and automated accounting systems. Examining the prices that result from bigger manufacturing, less laborious work, or better quality is something you should think about.
  • Availability of Capital: Moreover, if chances of capital are not higher than the stated rate, the long-term benefits of automatic systems frequently take priority, thus becoming imperative.
Government Incentives: In certain regions, favorable government incentives may help in the promotion of automation technologies for solar panel manufacture. Evaluate these options as a way to aid with the initial costs.


The selection between manual and automatic solar tabbing and stringing lines is determined by your demands and production targets. Taking into account factors like production volume, labor availability, budget limitations, and future scalability will arm you with the information necessary to make the best trade-off between efficiency, quality, and cost-effectiveness. Recall that whereas manual systems have lower upfront costs, automated systems are profitable in the long term by offering such benefits as higher throughput, uniform consistency, and labor savings.

Finally, the choice can be made only after considering in detail the characteristics of production, volume consumption, and strategic goals in the distant future. Automatic tabbing and stringing processes, though require a high initial investment, are more suitable for high-volume production or large-scale utilities due to their efficiency and cost-effectiveness that can meet the growing demand for solar energy. With time, as the solar industry keeps developing, it becomes inevitable to adopt automation and digitization to remain competitive and to boost innovation in solar panel manufacturing processes.

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