The typical configuration shown in Figure 1 requires the installation of at least four power devices, plus any Surge Protection Devices (SPDs) required for the application. Figure 2 shows this type of application.

Power Transfer Load Centers integrate the load transfer and power distribution functions into a single equipment enclosure. At a minimum, this includes the transfer switch mechanism and the load center for distribution breakers. Communication devices and SPDs can also be supplied. A conceptual arrangement is shown in Figure 3.

Power Transfer Load Centers can also be configured with a service entrance breaker as shown in Figures 3 and 4. This arrangement can offer the same benefits described elsewhere for ASCO Service Entrance Automatic Transfer Switches. In addition, a quick connect panel can be added to simplify the connection of a temporary generator. This provides a “backup-for-the-backup” when a facility’s permanent generator is taken offline for service, a solution that complies with NEC Article 700.3(F).

Benefits of Component Integration

Power Transfer Load Centers offer multiple benefits to electrical professionals and end users. These benefits include the following advantages:

Simpler Specification and Procurement : With PTLCs, selection, specification, purchase, and shipping involve only one device. This streamlines workflows when compared to conventional installations that require four or more devices.

Reduced Space Requirements : Because PTLC components are consolidated into a single enclosure, they require less wall or floor space than separate devices mounted in dedicated enclosures.

Streamlined Installation : PTLCs install more quickly and simply than separate power devices. There is only one box to mount, not four or more. All intra-device conductors are connected at the factory, so installation processes are streamlined, and labor costs are reduced.

Assured Quality : Factory testing assures equipment functionality before it is shipped to the job site. In turn, this simplifies startup and commissioning. When compared to separately installed devices, these can reduce the overall installed cost of backup power systems.

Streamlined Support and Service : All of the devices and components in a PTLC are warranted and serviceable by one entity with one service call, regardless of component-level issues.

Summary

Power Transfer Load Centers connect normal or emergency power sources to an electrical distribution system and distribute power to respective downstream circuits. They accomplish this by incorporating a transfer switch mechanism and a load center inside a single enclosure. Integrating these devices reduces the total footprint of the equipment and streamlines installation. Because labor costs are reduced, PTLCs can offer lower overall installed costs when compared to conventional systems.