IPC-8701 Acceptability specs will help provide infrastructure for solar panel assembly
Solar panels have been in volume production for quite some time, but there are still just a limited number of standards to help original equipment manufacturers (OEMs) and electronics manufacturing service (EMS) companies determine whether completed modules meet design and assembly requirements. IPC recently published the first document to set common acceptance criteria for finished assemblies.
IPC-8701, Final Acceptance Criteria Standard for PV Modules-Final Module Assembly, was written as a first step toward providing an infrastructure that will help companies increase volumes, hold costs down and obtain common acceptance requirements between customers and manufacturers. Like IPC standards for printed boards and other products, it eliminates the inconsistency that comes when companies all use different criteria for determining acceptability requirements.
“EMS companies are getting different criterion from each customer,” said Jasbir Bath, senior director, Standards at IPC. “It’s challenging to work with these different acceptance criterion, in terms of training of manufacturing personnel on the line and manufacturing quality inspections.”
In 60 pages, IPC-8701 describes best practices for inspecting photovoltaic assemblies, providing more than 120 photos to clarify the differences between acceptable and unacceptable elements. It focuses on the housing and support electronics used by both crystalline silicon cells, which dominate shipments today, as well as thin film cells in photovoltaic (PV) module production.
“This covers things like ensuring that the frame is square, the junction box is connected properly and that the label is in place and readable,” Bath said. “It even includes packaging in the shipping box, describing the protective packaging that keeps panels from getting cracked or undergoing too much stress during transit.”
One section focuses on the frames that enclose and support the solar cells. These are critical for product quality and they help shape the perception of quality.
“IPC-8701 sets parameters for both incoming frames and acceptable quality after manufacturing,” Bath said. “It describes what’s acceptable in terms of scratches, sharp edges, burrs, etc. There are specifications on how large scratches can be.”
The document also sets acceptance requirements for the junction boxes of the module. Parameters for determining whether the plug-in terminals in the junction box pass or fail are also detailed.
also looks at the sealant, tapes and potting compounds used in the module. The bus bars that connect solar cells in the module are also described. One of the final production steps, creating labels, is also included. The legibility of serial numbers and manufacturing date codes are described along with information on where these labels should be placed.
For additional information or to purchase the standard, visit IPC-8701.
By Terry Costlow, IPC online editor