Configuration and Operation

Automatic Transfer Switch

When the Primary and Secondary inputs are both connected to Tripp Lite UPS Systems, the PDU operates as an Automatic Transfer Switch, providing redundant input power for high availability applications. Under normal operating conditions, the PDU will distribute power from the Primary input source, switching to the Secondary input source under certain conditions. The PDU will switch to the Primary source whenever it is Good according to the PDU input voltage definitions (see below).

Automatic Transfer Switch Source Selection

Upon power-up, the PDU looks for a source >85V. If it is unable to find a source >85V, it remains off.

Input voltage definitions:

99V

< Vin < 139V

Good

75V

< Vin < 99V

Fair

Vin < 75V

Bad

In normal operation (after power-up), if the selected source is no longer Good, the PDU will attempt to switch to the other source, but only if the other source is Good. If the selected source becomes Fair and the other source is not Good, the PDU will keep the loads connected to the selected source until the selected source becomes Bad, at which point the loads will be disconnected (note that the source selection doesn't change). After the loads are disconnected, they remain disconnected until the selected source becomes >85V, or until the other source becomes Good.

Preferred Configuration

The Automatic Transfer Switch function provides increased availability when the Primary and Secondary inputs of the PDU are connected to separate Tripp Lite UPS Systems that are connected to separate utility power sources. For maximum availability, Tripp Lite recommends using matching SmartOnline™ UPS Systems with pure sine wave output for the Primary and Secondary input power sources. The automatic transfer switch function will be compromised if the primary and secondary inputs are connected to the same utility power source.

Utility B

Utility A

Facility Circuit

Facility Circuit

Secondary UPS

Primary UPS

Secondary Input Cord

Primary Input Cord

 

Critical Equipment

PDUMH15AT

Loads

 

7

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Tripp Lite PDUMH15AT, PDUMH20AT owner manual Automatic Transfer Switch Source Selection, Preferred Configuration
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PDUMH15AT, PDUMH20AT specifications

Tripp Lite is renowned for its high-quality power distribution solutions, and the PDUMH20AT and PDUMH15AT models are prime examples of their innovative offerings. These power distribution units (PDUs) are designed to provide reliable power management and distribution in data centers, server rooms, and other critical environments.

The PDUMH20AT and PDUMH15AT come with several key features that enhance their functionality. Both models feature a compact design that allows for easy installation in rack enclosures or on standard server racks. The PDUMH20AT supports 20 outlets while the PDUMH15AT offers 15 outlets, providing ample power connectivity for various devices.

One of the most significant advantages of these PDUs is their versatility. They are equipped with multiple NEMA outlets, catering to a wide array of plug styles, which means they can accommodate different types of equipment without compatibility issues. Additionally, these units are built with a 10-foot power cord, ensuring flexibility in arrangement and connectivity to distant power sources.

Both models employ advanced surge protection to safeguard connected equipment from power surges and spikes. This feature is crucial for protecting sensitive electronic infrastructure in environments where electrical disturbances are common. Furthermore, they incorporate LED status indicators that provide real-time monitoring of the power status, ensuring users can easily assess their operational state.

The construction of the PDUMH20AT and PDUMH15AT is robust, featuring a metal housing that enhances durability while minimizing risks from environmental factors. These PDUs are built to withstand the rigors of a busy data center or server room.

In terms of installation, the PDUs come with mounting brackets, making it quick and easy to secure them in various configurations, whether vertical or horizontal. Additionally, the PDUMH series includes options for basic power distribution or more advanced features such as metering and monitoring, catering to different user needs.

Overall, Tripp Lite's PDUMH20AT and PDUMH15AT represent ideal power distribution solutions for any professional setting. With their blend of functionality, durability, and user-friendliness, these PDUs help ensure that critical systems operate smoothly and efficiently.
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