Application Example Turnkey Assembly Of An Industrial IO Board
An assembled industrial input and output board carrying a bank of relays and two rows of pluggable screw terminal blocks, fabricated and assembled in the same plant.
What Had To Be Solved
Field wiring boards take mechanical abuse that signal boards never see. Every terminal is tightened with a screwdriver, and that torque goes straight into the pad and the plated barrel. Relay coils switching inductive loads put transients back into the logic section.
Customer name, order volume and project dates are confidential and are not published.
Four Things That Had To Stop Happening
- Pads lifting when terminal blocks are tightened on site
- Insufficient separation between field wiring and logic sections
- Relay switching transients reaching the control circuitry
- Laminate that does not meet control panel flammability requirements
How The Board Answers Them
The bare board is built with a 0.025 mm plated barrel wall so the mechanical load is carried by the barrel rather than the pad alone, on laminate rated 94V-0 self-extinguishing. The layout keeps field and logic sections physically separated, and isolation resistance is verified above 10 to the power 12 ohms. Suppression components for the relay coils are fitted during assembly rather than left to site.
How The Board Is Produced
Each stage below runs inside our own plant in Fuyong, Shenzhen.
Stage 1
Bare board fabricated and open and short tested at 50 to 300 V
Stage 2
Solder paste applied through a stencil cut to the released paste layer
Stage 3
Surface mount devices placed and reflowed
Stage 4
Relays and terminal blocks fitted as through-hole operations
Stage 5
Assembled board inspected and packed on our own packing machines
Where Coordination Happens
The bare board and the assembly are handled by the same plant, so the surface finish, the panel format and the reflow route are decided together rather than negotiated between two suppliers. There is no shipping leg between fabrication and assembly, and no handover where damage or delay can enter.
Components are either bought here on a turnkey basis or consigned by you, with the split marked line by line on the bill of materials.
What Is Verified
- Bare board open and short tested at 50 to 300 V before any component is placed
- Stencil and board matched to the same released revision
- Post-reflow inspection before through-hole and manual operations
- Mechanical parts such as sockets and terminal blocks inspected as mechanical parts
- Functional test quoted and run against your own test specification
Where This Board Stands Today
The board is a standard catalogue item in the PCBA family. Fabrication and assembly take place in the same plant, so surface finish, panel format and reflow route are decided together.
Boards In The Same Family
Other catalogue items built on the same line to the same published tolerances.
Assembled Interface Board With Serial Ethernet And Edge Connector
Assembled Embedded Controller With Microcontroller Ethernet And Storage
Assembled Motherboard With Expansion Slot And Rear Port Cluster
Assembled Power Converter With Toroidal Inductor And LED Output Board
Questions About This Example
Can you tell me who this board was built for?
No. Customer names, order volumes and project dates are confidential and are not published. What is published is the board, its family and the process tolerances behind it.
Can you build the same board for me?
The board shown is a pcba catalogue item. Send your own files and we will quote against the same process and the same published tolerances.
What if my requirement is close but not identical?
That is the normal case. The capability tables define the envelope, and anything inside it can be built. Anything outside it we will tell you about before tooling.
Which industries does this apply to?
This example sits in industrial control, but the same board family is used across the other sectors in the catalogue as well.
Bring Us A Board With The Same Problem
Send the files and describe what has to stop happening. We will tell you which family and which tolerances solve it before quoting.