Case study of a data center that almost doubled its equipment in rooms sized before. PLCs read temperature and humidity at the foot of each rack, compare the values with their bands, find the hot spots and raise alarms, and send the data to a server, so the HVAC can cool only where it is needed. The sensors the room already had can be kept, and the PLC can also act on the HVAC.

The PDF covers the challenge, the three stages (find, measure, act), the system architecture with the signal list and the hardware used. Interactive version: data center rack monitoring case study online.