From Handbook of Electrical Design Details, Second Edition


The primary objective of all emergency and standby electric power systems is the safety of building occupants following a power outage. The danger to occupants during an outage is increased in the presence of smoke, chemical fumes, fire, or earthquake, adding urgency to any required evacuation of the building.

At the very least, emergency and standby power systems should provide lighting to assure the safe, panic-free exit of people from the building. If an outage occurs during a severe storm, emergency power systems will provide minimal lighting for people taking refuge in or remaining in the building until normal power is restored or the storm abates.

The secondary objective of these systems is the protection of property during loss of normal power. By picking up at least part of the load following an outage, minimal lighting will be restored, security systems will remain active, and critical building services such as heating in the winter or ventilation in the summer will be maintained.

Emergency or standby power will also permit orderly shutdown of computer systems or their continued operation to preserve vital data. In stores, active security systems can prevent theft; in large restaurants and cold storage warehouses, loss of perishable food can be prevented; and in factories, loss of materials in process can be avoided.

This chapter covers National Electrical Code (NEC) requirements for emergency systems and explains the differences between legally required and optional standby systems. Uninterruptible power supplies (UPS) and standby systems are discussed, and...

Products & Services
Emergency Call Systems
Emergency call systems are designated terminals used to call or transmit a need for attention. Emergency call systems may also be known as a panic alarms, man down alarm systems, duress systems, or a personal emergency response systems.
Lighting Inverters
Lighting inverters provide alternating current (AC) power for indoor, outdoor and emergency lighting, signage, and associated controls.
Circuit Protection Components
Circuit protection devices are used to protect electronic components from unwanted transients such as current and voltage surges, electrostatic discharge (ESD), lightning, spikes and other signals that can imperil the operation or damage the component.
Building Automation System (BAS) Integrators
Building automation system integrators combine sensors, controllers, actuators, PLCs, and operator interfaces into an automatic building asset management system. It is a means of increasing energy and labor efficiency.
Solar Lighting
Solar lighting converts solar energy into electrical energy to produce light for off-grid fixtures.

Topics of Interest

Overview An electrical surge is a sudden strong rise in voltage that can appear on power and communications lines entering homes, offices, and other facilities. Surges caused by natural or manmade...

Introduction This chapter briefly discusses where and why the need for standby generation arises and describes the systems that are included in a normal standby power generating set. Most standby...

Chapter List Chapter 5.1: Electric Measuring Instruments Chapter 5.2: Building Air Quality Chapter 5.3: HVAC System Control Equipment Chapter 5.4: Mechanical Equipment: Gearing and Enclosed Gear...

5.0 GENERAL NEED FOR EMERGENCY AND STANDBY POWER SYSTEMS Introduction Emergency electric services are required for protection of life, property, or business where loss might be the result of an...

7.1 INTRODUCTION This chapter introduces some of the main principles involved with substation control building and switchyard services. Such work is often left to specialist building services,...