APC UPS

How does the PDU work in the terminal power distribution of the computer room?

In view of the 7*24 hours operation requirements of IDC data centers and the increasing attention to power efficiency, rack PDU (Power Distribution Unit) has become an important part of data center infrastructure. To many people who are new to rack PDU, its function looks similar to a simple power strip, but in today’s complex computer room power environment, rack PDU not only provides power for IT equipment, but also provides switching, monitoring, metering, maintenance and data analysis functions to help computer room administrators balance loads and remotely manage power needs.

1. How does the cabinet PDU work?

Although there are many nuances to how a rack PDU works, the basic concept is not complicated. The rack PDU manages and distributes power, and is usually installed directly on the rack, taking power from the rack power supply (branch circuit), and distributing it from an uninterruptible power supply, utility power, generator, or other auxiliary power source (either AC or DC) to the various sockets of the PDU itself as needed. In short, the rack PDU is a single power input at the previous level converted into multiple power outputs.

2. Several factors related to cabinet PDU

According to actual application requirements, when purchasing cabinet PDU socket products, you need to consider factors such as voltage, phase, plug, socket type and function. Different variables will lead to many types of cabinet PDU products.

(1) Branch circuit: Power is distributed to server racks and cabinets through distribution boards, switches, or switchboards. Wiring can be run under the raised floor, in an overhead bus system, or both, and terminate at outlets near the server racks and cabinets. The load capacity of the branch circuit is measured in volt-amperes (VA) or kilovolt-amperes (kVA), calculated by multiplying the rated voltage by the rated current.

(2) Voltage and number of phases: In terms of power input, standard cabinet PDU usually supports single-phase or three-phase power input. It is necessary to select the appropriate input voltage based on the actual situation of the computer room and the AC voltage. Common input voltages are 110V, 200V and 380V, and the frequency is 50Hz or 60Hz.

(3) Output current and PDU plug type: The output current of the cabinet PDU needs to be determined according to the type of terminal device. Standard PDUs usually provide multiple output sockets to support the power supply of different devices. Common output socket types include national standard 16A, 10A, C13, C19, NEMA, etc. to accommodate different types of IT equipment. Therefore, it is very important to understand the type of equipment in the server rack or cabinet and the type and number of sockets.

(4) Functional configuration of cabinet PDU: Cabinet PDU products can be equipped with a variety of functional components, such as lightning protection and surge protection, filtering protection, overload protection, current and voltage display and other functional modules. At present, the new generation of intelligent PDU can also provide users with a variety of control methods, including local control and remote control. Local control is usually achieved through buttons or switches on the PDU device, which can manually control the power switch and current distribution. Remote control is usually achieved through a network connection. The PDU device can be remotely controlled through the Web interface, SNMP protocol, Telnet protocol, etc., to achieve remote monitoring and management of the power supply.