First Solar

the jdi group provided engineering, design, and programming, along with construction assistance, checkout and startup, for several environmental enclosures surrounding portions of the process equipment at First Solar. Each enclosure consisted of a new dedicated Process HVAC system designed to control the temperature and humidity as well as exhaust and fresh air supply. In addition, life/safety controls were included to maintain safe chemical levels through monitoring and automatic room purge if a safety device detects an unsafe level or in case of enclosure room breach detection.

Controls and instrumentation design for these systems included LEL sensors, E-stops, Door Sensors, Smoke Detection and a Master PLC OK Relay all wired into a Category 3 Safety system. PLC panel design, schematics, scope of work, construction drawings, sequence of operation, calibrations, PLC programming, HMI programming, and checkout/startup were some of the services provided. VFD controlled exhaust fans with room differential pressure feedback were used for PID control to maintain a negative room pressure during operation. Analog and digital IO were used to control, monitor and alarm process/safety/interlock signals for the enclosure. The HVAC system required control, status, alarming of temperatures, humidity, pressures, and airflow.