Box build assembly, or systems integration, is a comprehensive process in electronic manufacturing that involves assembling various components into a complete enclosure. Many sectors, including aerospace, automotive, and medical, rely on box builds to assemble critical control systems, battery management systems, and diagnostic devices.
Breaking Down a Box Build
There are five primary components of a box build:
- PCBs: The backbone of any electronic device. They provide the physical platform for mounting and interconnecting electronic components. Often, the entire box build assembly is designed around the PCB.
- Control panels: Switches, buttons, and display screens.
- Cable assemblies: Customized to handle the power and signal needs of the device.
- The power supply: AC-DC or DC-DC.
- Wire harness: Organizes and secures wires, cables, and subassemblies into a single unit, reducing installation time and increasing the device’s lifespan.
You can read a more detailed breakdown of the components here.
Assembly Methods
Box build assembly can be separated into two primary stages: mechanical and electrical. However, the assembly process always begins with getting drawings, specifications, and requirements from the client. Then, the manufacturer develops CAD drawings for client approval. Once the design is finalized, the components, including the off-the-shelf parts and custom-fabricated items, are sourced and carefully selected to ensure compatibility and compliance with application requirements.
The rest of the steps involved in each assembly stage are outlined below:
Mechanical
Before the entire assembly is built, smaller subsystems or modules, like PCBs and cable harnesses, are assembled. Each subsystem is tested to verify functionality. Mechanical components, like chassis, brackets, and fasteners, are mounted to the enclosure. Then, control panels and other control devices are installed on the front or back panel of the enclosure, and the structural elements and internal supports of the box build are assembled.
Electrical
The electrical phase of box build assembly involves wiring and connecting each component within the assembly using wire harnesses, cables, and connectors. PCBs are mounted and connected within the assembly, and power supply units, transformers, or circuit breakers are installed.
Quality Assurance
Testing
The QA process is the last step in box build assembly and involves various functional, electrical, and performance tests to ensure the final product operates as designed and meets application requirements.
Testing and programming is done per the customer’s specifications, which may include functional testing.
Packaging
In addition to testing, manufacturers must ensure the assembly is properly packaged and labeled. Shock-absorbent materials like wood, static-resistant bags, and moisture barrier bags are commonly used to prevent physical and electrostatic damage.
The packaging must also be properly labeled, although the labeling will vary based on the industry and where the box build is being shipped to. Generally, the labeling should identify what type of product it is and how that product should be handled. So, packaging for box builds would need to at least have fragile and electrostatic sensitive device labels, and a “heavy” label, depending on its size.
The military has more stringent labeling requirements, primarily outlined in MIL-STD-179. The best way to ensure compliance and total quality in packaging/labeling is to work with a manufacturer with an experienced in-house team, or if the manufacturer doesn’t have their own in-house team, to work with a third-party packaging and/or logistics company with military/defense experience.
Common Challenges in Box Build Manufacturing
Component Complexity
Box builds can vary significantly in complexity, incorporating everything from simple PCB assemblies to intricate systems with multiple interconnected sub-assemblies. Every component must fit physically within the box while functioning in harmony with the entire system. The more complex the assembly is, the more risk of design and integration errors and logistical challenges in sourcing the right parts.
Product Reliability
Box builds must operate reliably for extended periods, and their function is especially critical in sectors like defense/military, medical, and aerospace/aviation, where their functionality is a life-or-death matter. For example, box builds control the ventilation settings, battery pack, motor, and patient monitoring sensors in portable ventilators. If that box build were to fail due to, for example, an overheating issue within the assembly, the patient relying on the portable ventilator could lose their life.
This is just one example of a stressful situation that manufacturers are responsible for preventing. Additionally, reliability challenges are influenced by component complexity, as more parts generally mean more potential points of failure.
Prototyping as a Solution
Prototyping is often the first step to ensuring a box build’s design is accurate and reliable. In the prototyping phase of manufacturing, engineers collaborate to create detailed CAD drawings that outline the physical layout, electrical connections, and component placement, as well as a 3D model to visualize the assembly and identify any design issues early on. Some companies may even use simulation software to test a digital model before building a physical one. Simulation software allows manufacturers to test the digital model under varying conditions that mimic real-world scenarios, giving better insight into what could happen.
After the initial design is tested, parts are sourced, and a physical prototype is built and assembled. That prototype is subjected to various tests, similar to how the final product is tested, to ensure its functionality and reliability. If failures occur, engineers must figure out why these failures happened and how the design can be improved to prevent them. This stage of prototyping is called “iterative refinement.” The prototype is essentially changed multiple times until it meets all specifications.
PGF Technology Group’s Capabilities
PGF Technology Group is an industry-leading contract electronics manufacturer serving businesses in the aerospace, automotive, industrial, medical, and defense sectors. We not only specialize in box build assemblies but also PCB, cable, and wire harness assemblies. We ensure quality and reliability through prototyping, stringent quality control and testing requirements, advanced assembly techniques, and incorporating advanced heat dissipation solutions.
Visit our website for more box build-related resources, or contact us today to learn more about our manufacturing capabilities.
