PLC-controlled density test apparatus with dual pneumatic supply paths: compressed air through pressure regulation and nitrogen through flow control, converging at a manifold to feed five parallel test ports via solenoid valves. The system integrates a Venturi vacuum generator for negative pressure testing, with all pneumatic components—V1 through V10 solenoid valves, electronic pressure and flow regulators—orchestrated by a central PLC controller. This architecture enables simultaneous multi-unit leak detection with independent pressure and vacuum control, critical for high-throughput manufacturing test environments. Fork this diagram on Diagrams.so to customize valve counts, add sensor feedback loops, or integrate data logging interfaces. The modular manifold design allows scaling from 5 to N test ports without redesigning core pneumatic logic.