Multi-Contact (MC) is one of the pioneers of the PV industry, having developed the first professional photovoltaic connector on an industrial scale. For over 16 years the MC3 and MC4 have been the most successful connectors, showing best performance and reliability. The company’s success is based on long-term experience and expertise – we take a closer look.
Founded and headquartered in Allschwil, Switzerland, Multi-Contact now has 22 subsidiaries in 21 countries to offer easy accessibility of knowledge and a trusted selection of products. The company’s three manufacturing facilities are located in Germany, China, and the United States.
The company’s products comprise connectors, cables, and junction boxes for the photovoltaic industry. These production and assembly facilities enable Multi-Contact to meet local demands and to react to the dynamic PV market. Multi-Contact differentiates itself from competitors through high quality connectors, internal testing, and the rigorous quality controls performed.
The company’s products are suitable for the harshest of conditions; in coastal climates (salt mist) and on animal farms (ammonia resistance), in cold high alpine areas as well as in consistently hot regions. Multi-Contacts connectors have proven their durability in the harshest conditions possible.
MC’s innovative products serve photovoltaic systems globally. By using MC products you can expect durability and maximum efficiency and therefore satisfaction in your PV system.
Multi-Contact tests and research
Swisssolar (Basler & Hofmann AG) analysed PV-system errors to determine reasons why applications fail. MC then discovered that the interface between the module, connectors, wires, and the combiner boxes caused up to 50% of the errors in PV-systems. This research shows the importance of a quality connection. One crystalline module has at least twelve interfaces between the junction box, the connector, and its cable branch.
Each interface has potential for error and the risk of high contact resistance. These problems lead to profit loss dueto replacement, reinstallation, and service-hours.
According to Swisssolar (Basler & Hofmann)*, 59% of the errors at a PV-system will occur within the first two years.
Additional outcomes of this investigation showed that between the fourth and eighth years in service, the errors in the PV-System increase significantly. These errors occur due to material ageing or low quality not well dimensioned parts at the interfaces.
Multi-Contact focuses on the following points:
Reducing the potential error at each interface in short term => human factors.
Enhancing long term performance => electromechanical series, design, and the Multilam.
Human factors/crimping:
Potential risk of errors exists in the field. Installers are often driven by time pressure to be profitable. This can have an influence on the crimp quality (as mentioned by the PV branch association in Germany), and another source of error occurs if the wrong crimping tools or inserts are used. The installer has a high influence in the quality of parts used in the connection.
Using certified Multi-Contact crimp pliers and inserts, this enables the user to crimp accurately. Reducing the sources of human errors further, Multi-Contact sells pre-assembled strings as well as having partnerships with cable assemblers to reduce the manual crimping in the field where possible.
Multi-Contact minimises the risk of:
Crimping onto the isolation
Scorching, risk of fire
Crimping without a MC-tool
Deformation of engaging area
Not correctly engaged contacts
Scorching, risk of fire (heat, arcing)
A low pull-out force.
Connector and Multilam
Multilams are specially formed, resilient strips of copper alloy that are float mounted into a groove. By its constant spring pressure, the Multilam maintains continuous contact with the contact surface, resulting in a low and constant contact resistance. Multilam technology allows us to meet a very broad range of requirements allowing us to find solutions to the most severe constraints, including electrical, thermal and mechanical.
In harsh environmental testing under accelerated ageing, the company’s Multilam connectors like the MC4 and MC4-EVO 3 show the best long term performance in low contact resistance compared to the connectors of competitors. These performance tests are important indicators for in field long term performance due to the long lifespan of solar plants.
Not only do the MC4 and MC4- EVO 3 excel in lifespan, but also in safety.
Low quality connectors have short life spans and age faster. This might enhance the temperature of the connector to a higher contact resistance that can result in arcing and possible fire.
Multi-Contact uses its knowledge to enhance the safety of your PV-system and reputation if you use its connectors.
Advantages of Multilam technology
High current-carrying capacity
Minimal power loss
Minimal contact resistance in short and long term
High corrosion resistance
Red: established connector manufacturer
Blue: Multi-Contact MC4 Connector
Conclusion:
Quality and design of the connector are essential factors in this context, as its electrical performance immediately influences the overall performance of the power plant.
By using Multi-Contact products you can expect to have:
High Return On Investment through avoiding downtimes of the PV plant
Durability during lifetime, thereby saving maintenance costs
Simple and fast installation for high profitability
