- Project plans
- Project activities
- Legislation and standards
- Industry context
- Specialist wikis
Last edited 06 Jul 2021
Direct digital control systems
The Illustrated Guide to Mechanical Building Services, Third Edition (BG 31/2017), by David Bleicher, published by BSRIA in 2017, defines direct digital control systems (DDC) as: ‘…microprocessor-based with analogue inputs from sensors that are digitised. Some manufacturers make a distinction between DDC intended for primary plant control, such as for boilers, and those intended for secondary or terminal unit control such as fan coil units. Primary DDC units are freely programmable with control software configured for a particular method of plant control. DDC units intended specifically for terminal units usually have specific application software built in and only relatively minor configuration settings may need to be adjusted.’
Networked DDC systems: '...consist of two or more DDC controllers that are connected together enabling the exchange of information. Each controller usually controls one particular plant group and can operate autonomously in the event of communications loss. Typical examples of information exchanged between controllers are shared sensor readings, common plant start signals, and interlock signals between different plant groups. If a networked DDC system includes one or more permanent operator terminals it is classified as a building management system (BMS).'
 Related articles on Designing Buildings Wiki
Featured articles and news
Final report proposes improvements for UK-wide transport infrastructure.
The decarbonisation transition has begun.
Can smart homes take care of their occupants?
A showcase of She ethnic culture.
CIOB creates charter and publishes special report.
Response submitted by IHBC.
Designed to accommodate flooding or waterway traffic.
ECA states concerns over the Government's disparate plans.
Net zero carbon future - necessity, not choice - was the event's focus.