What is PDU? How To Choose the Right PDU for Your Data Center
What is a PDU?
A Power Distribution Unit generally referred to as PDU, earlier known in common parlance as a power strip, is an device fitted with multiple outputs intended for distributing electric power. The distribution of the power is mainly directed towards the racks of computers and networking equipment like servers located within a data centre of the device or equipment. The PDU is either a Basic or a Smart or Intelligent PDU. PDUs are either Horizontally mounted in a Rack and are called 1U or 2U PDUs depending on their height.(1U=1.75 Inches) or Vertically Mounted which are called “0” U. Generally there are Two Vertical PDUs mounted on either side of a Rack and are each connected to a different power source so as to maintain redundant power supply to the equipment connected.
Unlike a power strip, Power distribution units or PDUs are more advanced and are used to bring power to the IT equipment and are installed in a Server Rack.They are used for distributing and controlling electric power in a data centre. The basic PDUs are designed to make standard electrical outlets accessible for the data centre equipment without remote access ability or monitoring and other intelligent features.
From the available PDUs, it becomes essential to pick the ideal one for the circuit and encourage smooth functioning. Here are some questions that help understand the power distribution unit and smart PDU configuration.
Questions to ask while selecting a PDU for your data centre
What are the different types of Outlets or Connectors used?
In most of the PDUs used in the Data Centers, the outlets used are IEC 60320 standard outlets or in some cases outlets like Schuko or NEMA outlets. The commonly used Outlets are IEC 60320 C13 or C19 types. For a desired output of 10 Amps a C13 Outlet is used and and for 16 Amps a C19 Outlet is used both for 250 VAC. As there is a need for higher density data centers where the higher power requirement also pushes up the temperature ratings of the outlets. The C13 and C19 Outlets are rated for 70 degrees C. For higher temperatures upto 150 degrees C, Elcom offers C15 and C21 Outlets; Elcom’s PDUs also offer these options for high density and high current applications. All these have UL and VDE Safety approvals.
Elcom also offers NEMA (National Electrical Manufacturers Association) Standard Outlets and also PDUs with these types of outlets.
2. How many outlets does it have?
The number of outlets integrated into any PDU generally depends on the specifications given by the customers depending on the servers and other appliances connected in a Server Rack. Generally a combination of C13 and C19 Outlets are configured in each branch which decide the size and length of the PDU, but the total length of the PDU and is limited because of the height of the server cabinet. A standard and basic PDU will have 24 to 40 or more outlets in its configuration. However, some PDUs have different configurations. These PDUs often divide the circuit into various branches, and each branch works according to the fuse or its circuit breaker. This alternating phase PDUs distributes the power on a per outlet basis in the equipment.
3. Are the outlets colour-coded?
To ensure easy circuit identification, it may not be necessary to integrate colour-coded outlets unless specified by a user, but colour coding of the branches along with thecircuit breakers can be used for better identification of the branches or circuits. It also reduces the risk of overloading as it makes identification easier of the circuit configuration. Since traditional PDUs have outlets grouped according to the branches of the configuration, the high-density PDUs organise the alternating phase outlets to reduce cord clutter, simplify the load balancing in the circuit and allow the integration of more outlets in the same amount of space.
4. What is the footprint of the PDU?
Before finalising the PDU for the circuit, it is essential to consider the footprint and its impact. Nonetheless, the 0U PDUs are convenient and do not consume equipment space; considering their footprint, impact on heat dissipation and approach to cable management help with finding the ideal configuration. The ones with ultra-low profile designs adjust in limited space along with increasing the airflow and operational efficiency within the circuit. Analysing the footprint of the PDU becomes significant primarily when the circuit uses multiple PDUs to support power supplies.
5. Does the PDU provide metering capabilities?
PDUs integrated with metering capabilities significantly reduce the risk of overloading the circuit. It also helps the data centre operators with planning the capacity of the circuit and optimises the use of energy. The input-metered PDUs monitor the circuit breakers and phases in real-time, preventing any damage to the circuit. The outlet-metered PDUs generally monitor the power load at the outlet level. And the network-connected PDUs allow the technicians to view the collected data remotely.
6. Does the PDU have switched outlets?
Switched outlets are general features, and this makes the applications more accessible. It allows technicians to power on and off along with remotely reboot equipment and sequencing the equipment’s power control. This outlet provides the control that helps prevent other outlets’ unauthorised use.
Elcom International offers a full range of PDUs.
Elcom International’s intelligent, high-quality, reliable and technologically advanced PDUs enhance operational efficiency and data centre uptime. By accommodating customisation, Elcom International makes world-class quality PDUs manufactured and engineered with different configurations possible . Distinguished and customised based on mounting, inlets and outlets, type of protections and other components, Elcom International caters to a range of PDUs-related requirements with fully functional solutions.
