NIST 800-53 REV 5 • PHYSICAL AND ENVIRONMENTAL PROTECTION

PE-11(1)Alternate Power Supply — Minimal Operational Capability

Provide an alternate power supply for the system that is activated organization-defined parameter and that can maintain minimally required operational capability in the event of an extended loss of the primary power source.

CMMC Practice Mapping

No direct CMMC mapping

NIST 800-171 Mapping

No direct NIST 800-171 mapping

Related Controls

No related controls listed

Supplemental Guidance

Provision of an alternate power supply with minimal operating capability can be satisfied by accessing a secondary commercial power supply or other external power supply.

Practitioner Notes

This enhancement requires an alternate power supply (like a generator) that can maintain at least minimal operational capability during an extended power outage — longer than what your UPS batteries can cover.

Example 1: Install a diesel or natural gas generator sized to power your critical IT infrastructure (servers, network equipment, cooling) for at least 24-72 hours. Configure an automatic transfer switch (ATS) so the generator starts and takes over within seconds of a utility power failure.

Example 2: If a permanent generator is not feasible, contract with a generator rental company for emergency power. Have a pre-negotiated agreement so you can get a portable generator delivered within hours. Ensure your electrical panel has a manual transfer switch connector ready for a portable generator hookup.