Direct Digital Control Systems: Application · Commissioning offers an insightful examination of the critical role of the DDC system in the commissioning process. Included is solid coverage of microprocessor-based control systems combined with the prools and procedures needed to effectively integrate DDC system validation into systems commissioning. This field handbook is an everyday reference on Direct Digital Control for commissioning personnel. Whether designer, contractor, air balancer, technician, vendor, commissioning agent, owner, operator or student, increasing one's knowledge of DDC control systems will directly improve project performance.