It’s important to test both the individual components, and the system as a whole.
Component-only Testing vs. Systems-tested and Listed for Safety
Testing multiple components together as one working system for safety is paramount. Having individual components, some with safety approvals and some without, combined to work as one “product” without a system test can be dangerous.
For example, using a controller that does not have the proper fuse size (for current protection) or wire harness gauge could lead to system damage, shock or even fire. When a solar lighting product or system does not carry a recognized mark for safety, all major electrical components (solar panel, controller, battery, fuse protection, etc.) should carry a safety mark.
Self-Imposed Safety Marks versus Independent Safety
A CE Marking is a European marking of conformity indicating that a product complies with all applicable European laws or directives. The European Community established the CE marking system to ensure free movement of products between member countries and to remove internal barriers to trade. The CE marking is legally required in the European Union (EU) and applies to a variety of product categories.
Most products bearing the CE mark are not required to be third-party certified and are not subject to ongoing factory surveillance of production. As a result they may not be compliant with applicable U.S. product safety standards and they are not considered to be a listed product as defined in NFPA and ICC model codes and standards.
Examples of OSHA recognized NRTLs include UL, CSA, FM, TUV and ETL. UL is an independent third party organization that has no bias nor sales goals to achieve. UL has a rigorous testing phase and conducts regular factory audits to ensure manufacturers maintain minimum safety standards to ensure consumers are receiving a tested, safe system or product.
For further information on the differences between UL and CE please visit their website.