I have made few programs for Delta PLC DVP Series Units using ladder logic with usage of digital and analog IO’s and Modbus links to external systems.
Rain Water Filtering Station
My program had to manage collecting and filtering of rain water for reuse in toilets in office building in Warsaw, Poland. Building has two underground floors and eight office floors with overall floor area of 26 850 m2 and height of 30 m.
Filtering Station consisted of two tanks:
- Main tank
- filled with water collected from the roof - about 100 m3 of capacity,
- Buffer tank
- filled with water from main tank after refining in filtering system - about 1,5 m3 of capacity.
Main functionality was to manage collected water, refine it through filters and prepare for usage in buffer tank. When there was no rain buffer tank was filled with water from city water supplies. When there was to much of rain water it was drained to sewage system. For continuous work system had pump set which pumped filtered water to the toilets in the whole building.
My program needed to collect data from numerous sensors, manage valves, filtration system and pumps. It also had timers in between for proper pump set maintenance. System was connected to building BMS via MODBUS RTU.
Cooling system management
Where: Radiotherapy section of Hospital, Warsaw What: Cooling system and ventilation automation
This program managed timed work of two independent 2 pump sets for continuous work. It also had to manage freon leak from cooling system. When freon sensor alarmed about leak program had to open fire dumper, air throttle and turn ventilators on. Program managed also visual and sound alarm to notify people nearby about leak. After freon sensor informed that leak is gone, system kept ventilation on for few minutes more. Alarm could be reset only by responsible technical person after confirmation that leak is gone.