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QUIZ: Grounding Electrical Systems
These days, multiple power sources can be present in a single building or structure. Many of these are what the National Electrical Code (NEC) calls separately derived systems. Transformers, batteries, fuel cells and generators can supply these systems. An electrical system produced by a generator is either required to be grounded as a separately derived system or it is not, and the key to this is the transfer equipment.
QUIZ: Fire Alarm Survivability Requirements
Pathway survivability requirements are an often-misunderstood area of fire alarm systems. Test your knowledge of the requirements in NFPA 72, 2016 edition.
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