In modern electronics manufacturing, seamless integration of production equipment is crucial. The SMEMA standard and its successor, the Hermes protocol, play central roles by providing clear guidelines for mechanical and electrical interfaces. This article explains how adhering to these standards can optimize your production processes.
What is the SMEMA Standard?
The SMEMA standard was developed to standardize the interface requirements for production equipment used in surface-mounted printed circuit boards manufacturing. It allows different machines to be integrated seamlessly, reducing time to market and fostering innovation.
Mechanical Interface Requirements
Single-Lane Conveyors
- Conveyor Height: Adjustable between 940 and 965 mm.
- Fixed Rail: The front rail is fixed, while the rear rail is adjustable.
- Conveyor Width: Adjustable to accommodate various PCB widths.
- Edge Clearance: Maximum of 5 mm.
- Tooling Pins: Positioned at the front edge of the PCB.
- Maximum Gap: 19 mm.
- Lead-in: At least 3 mm with a maximum angle of 30°.
Dual-Lane Conveyors
- Conveyor Height: Adjustable between 940 and 965 mm.
- Conveyor Width: Independently adjustable between 50 mm and 216 mm.
- Asynchronous Control: Each lane is independently controllable.
- Edge Clearance: Maximum of 5 mm.
- Maximum Gap: 19 mm.
- Lead-in: At least 3 mm with a maximum angle of 30°.
- Electrical Interface: Each lane has an independent transfer interface.
Electrical Interface Requirements
- Inter-Machine Control: Signal lines "Board Available" and "Machine Ready".
- Inter-Machine Connections: Female interface connectors meeting standards.
- Interface Signal Logic: Switches 30 VDC at 10 mA with a "LOW" output of maximum 0.8 VDC.
The Successor – The Hermes Protocol
Since the end of SMEMA, the Hermes Protocol (IPC-HERMES-9852) is the new standard for machine communication in SMT manufacturing. This protocol offers numerous improvements over the old SMEMA standard:
- Simpler Wiring: Ethernet-based communication (TCP/IP).
- Enhanced Data Transmission: Uses XML for transmitting control messages and product data.
- Reduced Number of Barcode Scanners: Only one scanner required at the beginning of the line.
Advantages of the Hermes Protocol
By adhering to the Hermes protocol, manufacturers can further enhance the efficiency of their production lines, ensure compatibility between different machines, and ultimately reduce production costs.