Solar String Combiner Boxes with Monitoring: Supervision Made Easy

What happens when a module fails in an industrial scale PV solar rooftop installation and goes unnoticed for an extended period? 

The answer is: energy losses that, if left undetected for a long time, convert into economic losses.

Most industrial-scale PV plants equip string combiners and monitoring equipment to detect such failures quickly and minimize the associated energy losses. But what exactly is a String Combiner and Monitoring Box? What other advantages does it offer?

Within this article, we will address the answers to these questions and more.

What Is a String Combiner and Monitoring Box?

String Combiner and Monitoring Boxes (SCB-SMB) are “smart combiners” that collate multiple strings of solar PV modules to give a single main output to inverters. They are solar junction boxes that consolidate incoming power into a single feed and distribute it to a solar inverter, resulting in wire reduction. In simple words, the combiner box’s function is to bring the output of several solar strings together.  Each string conductor connects to a fuse terminal, and the output of the fused inputs is combined onto a single conductor, which connects the box to the inverter.

This is the most basic configuration of the combiner box. However, once it is connected to the solar PV module, additional features are typically integrated into the combiner box, like disconnection switches, monitoring equipment, remote rapid shutdown devices, etc.

What Makes a String Combiner Box Essential for a Solar PV Module:

While the primary function of a string combiner box is to combine the output of multiple solar panels into a single bus, its real-world applications extend beyond its primary function.

  • Combiner boxes are useful in projects of all scales. Combiner boxes in residential applications can bring a small number of strings to a central location for easy installation, disconnection, and maintenance. In commercial applications, combiner boxes of various sizes find usage to capture power from varying building types. Furthermore, in large-scale industrial projects, combiner boxes enable site designers to maximize power while distributing combined connections while lowering labour and material costs by distributing combined connections.
  • Strategically placed combiner boxes in solar PV modules can help to reduce power loss. The combiner box should be placed between the modules and the solar inverter to maximize output.
  • Solar combiner boxes improve inverter protection and reliability by safeguarding the system from excessive current and voltage overcharge.

Adding Monitoring to the Combiner Box:

With renewable energy production gaining traction worldwide, solar PV modules for collecting solar energy are leading the market in many countries. According to an NPR report, system owners are looking for new ways to keep their PV modules running at peak performance with its widespread adoption. String monitoring is one of the most important ways to keep track of solar PV panels and identify faulty components in the shortest amount of time.

  1. String monitoring on a solar PV module is incredibly significant for quickly identifying potential power losses in the PV generator and ensuring the module’s long-term performance level remains the same. 
  1. With a combiner and monitoring box, you can stay proactive with the least amount of effort. String Combiner and Monitoring boxes supervise ongoing processes at the site and detect if any components have become faulty in real-time. They are especially beneficial when multiple processes fail, which are undetectable to the human eye. For this purpose, our high-performance combiner boxes include an in-built monitor, which streamlines the supervision process, reducing the risk of damage due to leaks, loose connections, and other issues.  

What Should Be Considered While Selecting a Combiner Box?

The String Combiner Box is the first piece of equipment connected to the solar module; thus, its quality should be the most crucial consideration when choosing one. The selected equipment must be thoroughly inspected to ensure that it complies with all the applicable certifications and the manufacturer is an ISO-certified company.

Before selecting a combiner box, it’s also vital to evaluate the project’s technical requirements. Because our resilient combiner boxes are designed to last the life of the solar project, it’s critical to determine what specifications are required so that the combiner and monitoring boxes can be customized to meet that criterion.

Why Should You Choose VNT?

Our combiner box houses multiple vital components such as fuses, disconnector switch, surge protection device, cables & busbars. Furthermore, our string monitoring boxes (SMBs) are a more advanced version of SCBs in which the PCB board/Monitoring board is consolidated into the SCB, effectively fulfilling the following two purposes:

  1. The combination of multiple strings of solar PV modules provides a single main output to inverters.
  1. Monitoring various parameters such as input string electrical parameters, temperature, fuse status, SPD status, disconnector switch status, etc.

Our string combiner with monitoring box produces precisely measured value recordings of all electrical indicators, allowing you to monitor your solar PV plant safely and accurately. Our string combiner and monitoring boxes have a 100% success rate, so when you choose VNT, you are guaranteed to acquire competent and durable equipment.

What Our Highly Engineered Combiner with Monitoring Box Offers:

Our strict engineering design standards and world-class manufacturing facility at VNT enable us to build superior quality products with unrivalled reliability at a competitive price, ensuring a long product life even in challenging environmental conditions. The following set of features marks our solar combiner and monitoring box apart from the competitors in the market:

  • Fully Customizable: Upto 32 PV string inputs.
  • Precision: Measurement accuracy of ±0.5%
  • Variety: Available from 600 to 1500 VDC
  • Competent: Capable of individual string level monitoring
  • Quality Assurance: In compliance with IEC 61439-1&-2 standards and 100% factory tested in compliance with ISO 9001:2015
  • Competent: Integrated Surge protection devices, built-in touch-safe fuse and fuse holders, DC isolator, among many other components.

Additionally, we back our product with commissioning, maintenance and service support to achieve maximum yield from a solar plant across its lifecycle. 

VNT- A Trusted Name in Solar Solutions

As the photovoltaic market expands due to advancements in photovoltaic (PV) modules, so do the manufacturing advancements in combiner boxes regarding reliability, added features, and scalability. VNT has designed, delivered and installed its string combiner boxes at various industrial-scale projects throughout India. Our SCBs enable you to monitor and measure the system performance in real-time while also ensuring exceptional system safety.

Our String Combiner and Monitoring Boxes are spread across India, installed in solar plants under challenging terrains, high altitudes, and coastal areas, demonstrating our expertise in the solar domain. As key players in this field, we design and engineer solutions for our customers while keeping longevity and excellence at the forefront of our operations.

Our innovative design and exceptional quality in solar solutions were recognized and honored in 2019 when we received the Business Excellence Award in the “String Combiner Box Manufacturer of the year” category.

Contact us to learn more about how our industry-leading solutions in various verticals can help you grow your business.

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