Main sources of risk

Not only the selection of quality components, but also their correct handling is crucial for the plant's profitability. There are three main risk sources, which can lead to the mentioned consequences and put the neat functioning at risk.

Quality versus low-end product

With the Original Stäubli MC4 connectors you benefit from over 20 years of experience in the photovoltaics' industry as well as from the outstanding technical characteristics of the innovative MULTILAM advanced contact technology. Thanks to their constant spring pressure and patented design, MULTILAM feature multiple contact points to improve connection and energy transfer, resulting in a constantly low contact resistance. This ensures safe and long-life operation and reduces downtime and service cost significantly. Furthermore, risks of  power loss, hotspots or fire, that could lead to enormous reconstruction costs are reduced to a minimum.

Cross-connection

Mismating or cross-connecting easily entails technical and legal risks. Therefore, it is important to always use Stäubli components during the whole installation process (from module to inverter). Factors that are causing incompatibility:
 

• Deficient technology and product material
• Differences in production process and quality standards
• No aligned tolerance zones to ensure tightness as well as sufficiently high contact forces
• No chemical compatibility of all raw materials (including production and auxiliary materials)
• Changes in the production process without respecting possible interactions
• Disrespect of the fact that certification and standards are given for one product from one manufacturer; those are not manufacturer-independent
   

There are various standards (UL1703 and IEC62548 installation norm) and regulations - which disallow cross-mating of two connector parts of different brands. Studies and field based data prove very clearly that there is no compatibility between two different connectors. Furthermore, the certification for the EN50521 product norm will be terminated by cross-mating. Always keep in mind that submitting a case to the court, e.g. in the event of a fire, involves high costs and bother over a long period.

The previously mentioned problems and risks may cause by cross-connection. Several manufacturers claim to produce “Stäubli compatible” components. Doing cross-connection, however, is not permitted under any circumstances and may lead to severe damages.

Defective installation/crimping

Another risk for the neat functioning and profitability of a PV plant may result from defective installation. This often results from false crimping. Therefore, we highly recommend to always make sure to use certified crimping tools in order to ensure correct and safe installation.

False crimping and too low crimp forces may lead to:
 

• Non-fulfillment of the norm criteria
• Unstable contact resistance
• No gas-tightness
   

These mentioned problems and risks may also occur due to a defective installation.