Climate Chamber Control

Introduction :

Our customer in this project is one of the biggest factories in Egypt that is running under supervision of Military. They have an old Climate chamber since 1983 that was working well until it’s control unit was damaged.

The Challenge :

Depending on the same components used for heating, cooling, humidifying and de-humidifying the workspace inside the Climate chamber, we needed to replace the old control unit with a new one based on National Instruments hardware, providing a better control on the temperature and humidity profiles requested.

User can define the Temperature and Humidity profile that is required to make the workspace reach during his tests, also the duration that the control system should maintain this Temperature and humidity setpoints.Finally These profiles should be saved on an SD card.

Solution :

We chose NI sbRIO 9641 (32 AI, 32 Industrial DO), that will act as a PAC rather than traditional PLCs used. Along with the controlling board (sbRIO) we used the NI 9802 C Series SD Card Reader/Writer to save, edit, or delete the required program of the user. We built our program on the 3 Layers (Host PC, Real Time, and FPGA), The FPGA is used for signal Acquisition and Scaling for the Sensors Readings (Rh, and Temperature sensors), also is used in controlling the HVAC circuit of the Climate chamber via its Industrial Digital output Ports. Real time Program is based on a master/Slave Design pattern, The master Loop is designed to control the slaves, one slave is dedicated to SD Card Reading and Writing, and the other Slave is for implementing the Control Algorithm of the Climate chamber circuit to reach the set points mentioned in the user-defined programs The host PC Program is responsible for monitoring, Data logging and report generation.