This FAQ has been written for NEAL (North East Africa and Levant) region. If you are looking for information for another region, please select the correct country from the top-left dropdown in the page and 'Navigate to Browse FAQs' in the Support menu.
Automation redundancy can be accomplished via three methods - cold, warm and hot.
Cold Redundancy
Cold redundancy is for those processes where response time is of minimal concern and may require operator intervention. As an example, take two belt presses, each with its own dedicated control panel. If one belt press becomes inoperable, the operator can resume operation by simply starting the other press.
Warm Redundancy
Warm redundancy is used where time is somewhat critical but a momentary outage is still acceptable. In this scenario, a momentary bump can be expected. During this bump, the valves, motors and other devices might shutdown temporarily, and the sensors may not report back to the PLC system during the bump.
Hot Redundancy
Hot Redundancy is used when the process must not go down for even a brief moment under any circumstance. An example of a hot redundancy system application is a membrane or BAF application. In both instances, the process may not require the hot redundancy capabilities, but during a backwash, redundancy could be critical.
Released for:Schneider Electric Egypt and North East Africa
