NEC 700, 701 and 702

I

Isaiah

Senior Member
Location
Baton Rouge
Occupation
Electrical Inspector
My understanding is NEC requires Emergency and Legally Required Standby Systems to have automatic transfer switches - but optional standby can be manual.
Are there any exceptions to 700 and 701 requirements that would allow manual transfer only operation in lieu of automatic?


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It's a matter of timing. 700 requires emergency power to come on within 10 seconds. 701 requires legally required standby power to come on within 1 minute. You can't achieve either requirement with a manual transfer, as no human could discern the need for backup power and respond quickly enough.
 
Give the loads that are supplied by emergency and legally required standby systems, there can be no provision for the use of a manual transfer switch. These loads must be connected automatically for safety reasons.
 
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