Auxiliary Power Supply

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Auxiliary Power Supply

What is Auxiliary Power Supply?

Auxiliary Power Supply, A backup electrical source that supports critical equipment during primary power loss or fluctuations.

Description

An auxiliary power supply (APS) provides interim or supplemental power to critical systems such as fire alarms, telecom racks, and PLC controls. APS units include batteries, DC-DC converters, or small generators that ensure uninterrupted operation during short outages or until standby generators take over. Design considerations include load profile, autonomy time, and recharge rate.

FAQs

  • What is the difference between APS and UPS?

    APS may supply DC loads; UPS conditions the AC output to IT equipment.

  • How long does APS power last?

    From minutes to hours, depending on battery capacity.

  • Who installs auxiliary supplies?

    Electrical contractors follow manufacturer guidelines.

  • Is automatic switchover required?

    Yes, contactors or diodes prevent back-feed.

  • Are batteries sealed?

    VRLA or lithium-ion cells reduce maintenance.

  • Can solar charge APS batteries?

    Photovoltaic chargers extend autonomy in remote sites.

  • What codes govern APS?

    NFPA 70, NFPA 110, and IEEE Std 485 sizing.

Fun Fact

Fun Fact: Spacecraft use auxiliary power units fueled by hydrazine to supply systems during launch and landing phases.

CSI Code

26 33 00

NAHB Code

2640