SURFACES

BACKGROUND

[0001] Computing centers such as data centers generally include a large number of computing devices. The computing devices can include, for example, servers, switches, routers, storage systems, and the like. A rack may provide a standardized structure to support and mount the computing devices. A power distribution unit (PDU) can also be mounted on the rack to provide electrical power to the computing devices.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Some examples of the present application are described with respect to the following figures:

[0003] FIG. 1 is a perspective view of an example power distribution unit (PDU), including receptacles on the front and back surfaces;

[0004] FIG. 2 is a perspective view of an example PDU, including receptacles on the front and back surfaces;

[0005] FIG. 3 is a perspective view of an example PDU, including receptacles on the front and back surfaces;

[0006] FIG. 4 is a perspective view of an example PDU, including receptacles on the front and back surfaces, mounted on a rack;

[0007] FIG. 5 is a perspective view of an example PDU, including receptacles on the front and back surfaces, mounted on a rack; and

[0008] FIG. 6 is a perspective view of an example first and second PDU, both including receptacles on the front and back surfaces, and both mounted on a rack. DETAILED DESCRIPTION

[0009] Examples described herein relate to power distribution units (PDUs) with power receptacles on the front and back surfaces of the PDU. In addition to computing devices such servers, networking devices and storage devices that can be mounted in a rack, a PDU can also be mounted in a rack to provide power to such computing devices. For example, the computing devices can have power cords that are plugged into the power receptacles (or power outlets, power connectors) of the PDU. The PDU can include circuitry to convert alternating current (AC) power to direct current (DC) power for the computing devices. The PDU can also include a circuit breaker for the power receptacles to protect the computing devices from damages caused by overload or short circuit, by interrupting current flow to the computing devices.

[0010] A PDU can be vertically mounted in the rear of the rack to avoid taking space in the rack, where the computing devices can be mounted. An equipment or computing device mounted in the rear portion of the rack is referred to as a "zero U," as it takes up no space in the rack. Rack-mountable computing devices and equipment are measured in standard heights of 1.75 inches, referred to as "rack unit" or a "U." Accordingly, a PDU can be a zero U device when it is mounted in the rear of a rack and does not take up space in the rack.

[0011] Examples herein describe a PDU with receptacles on both sides of the PDU (e.g., a front surface and a back surface or on opposite surfaces). In particular, the described PDU is a zero U (0U) vertical PDU with receptacles on both sides of the PDU to provide a high receptacle count in a single PDU chassis, while adhering to the back of the rack keep out zone (i.e., keeping the PDU chassis out of the serviceability area in the back of the rack).

[0012] In one example, a PDU includes a front surface including a plurality of receptacles to couple a first plurality of computing devices to the PDU and a back surface including a second plurality of receptacles to couple a second plurality of computing devices to the PDU.

[0013] In another example, a PDU includes a first plurality of power receptacles on a front surface of the PDU to distribute power to a first plurality of computing devices coupled to the PDU, and a second plurality of power receptacles on a back surface of the PDU to distribute power to a second plurality of computing devices coupled to the PDU. The PDU includes a first set of mounting holes on a left surface of the PDU to removably attach mounting buttons to mount the PDU to a rack enclosure, and a second set of mounting holes on a right surface of the PDU to removably attach the mounting buttons to mount the PDU to the rack enclosure.

[0014] In another example, a rack enclosure includes a rack including vertical rack columns and a PDU. The PDU includes a first plurality of power receptacles on a front surface of the PDU to provide power to a first plurality of computing devices coupled to the PDU, and a second plurality of power receptacles on a back surface of the PDU to provide power to a second plurality of computing devices coupled to the PDU. The PDU includes a first set of mounting holes on a left surface of the PDU and a second set of mounting holes on a right surface of the PDU. The PDU also includes a plurality of mounting buttons removably attachable to the first or second set of mounting holes to removably mount the PDU to a vertical column of the rack.

[0015] Referring now to the figures, FIG. 1 is a perspective view of an example power distribution unit (PDU), including receptacles on the front and back surfaces of the PDU. PDU 100 includes a front surface 116 (or front side) and a back surface 126 (or back side) opposite the front surface 116. Front surface 116 includes a plurality of receptacles 106 to removably plug in power cords of computing devices such that the PDU 100 can provide power to the computing devices. Similarly, back surface 126 includes a plurality of receptacles (not shown) to removably plug in power cords of computing devices such that PDU 100 can provide power to the computing devices. Accordingly, PDU 100 can simultaneously provide power to a first plurality of computing devices coupled to the first plurality of power receptacles 106 on the front surface 116 of the PDU, and a second plurality of computing devices coupled to the second plurality of power receptacles 106 on the back surface 126 of the PDU 100. Computing devices can include rack-mountable computing devices such as servers, networking devices, storage devices, etc.

[0016] By providing power receptacles 106 on both surfaces 116 and 126 of the PDU 100, PDU 100 can provide power to a more computing devices compared to a PDU having receptacles on only one side. Moreover, PDU 100 can provide a high receptacle count at a lower cost compared to the cost of two PDUs. In certain examples, the number of receptacles 106 on the front surface 116 can be equal to the number of receptacles 106 on the back surface 126, however, examples are not so limiting. In other examples, the number of receptacles 106 on the front surface 116 and the back surface 126 can be at least 48. Furthermore, each receptacle 106 can be a standard power outlet for receiving a standard plug. For example, in the case of a server rack or data center power system, each receptacle 106 can be an International Electrotechnical Commission (IEC) standard C19 or C13 outlet configured to receive a standard C14 or C20 plug.

[0017] PDU 100 also includes mounting buttons 102 on a left surface 112 (or left side) of the PDU 100. Mounting buttons 102 can be removably inserted into mounting holes (not shown) on the left surface 112 of the PDU 100. Mounting buttons 102 include any connectors or mounting features to engage with

corresponding mounting features 104 on a vertical rack column 114 (or vertical rack surface) of a rack. Each mounting feature 104 can be an opening, recess, or cavity in the vertical rack column 114, to receive the mounting buttons 102. In certain examples, mounting feature 104 can include a circular recess and a slot, such that mounting button 102 can be inserted into the circular recess and slid along the slot to secure the mounting button 102 within the mounting feature 104.

[0018] PDU 100 includes a breaker box 108 (e.g., a first breaker box), associated with the receptacles 106, on the front surface 116 of the PDU 100. Breaker box 108 can include a number of circuit breakers 118 to protect the computing devices from damage caused by overload or short circuit. Similarly, the back surface 126 a breaker box 108 (e.g., a second breaker box) for the receptacles 106 on the back surface 126. In some examples, breaker box 108 can be block member protruding from the surfaces 116 and 126 of the PDU 100. In other examples, breaker box 18 can be flush (i.e. non-protruding) from the surfaces 116 and 126 of the PDU 100.

[0019] PDU 100 also includes a power cord 120 for providing power to the PDU 100. For example, PDU 100 can be coupled to a main power supply or to a backup power supply, such as an uninterruptible power supply (UPS), via the power cord 120. Power cord 120 can be located on a top surface or a bottom surface of the PDU 100. In some examples, a width of the PDU 100 may not exceed 52 millimeters (mm). [0020] FIG. 2 is a perspective view of an example PDU, including receptacles on the front and back surfaces. In the example of FIG. 2, the mounting buttons 102 are located on a right surface 122 (or right side) of the PDU 100. Mounting buttons 102 can be removably engaged with mounting features 104 on the vertical rack column 114 of the rack. By providing receptacles 106 on the front surface 116 and the back surface 126 of the PDU 100, the receptacle count can be increased at a significantly lower cost (e.g., compared to using two PDUs), to support additional computing devices within the rack. Further, by mounting the PDU 100 on its side (i.e., vertical side), the body of the PDU 100 (i.e., including the power receptacles 106 with power cords coupled thereto and the breaker box 108) can be kept out of the serviceability area or keep out zone of the rack.

[0021] FIG. 3 is a perspective view of an example PDU, including receptacles on the front and back surfaces. In the example of FIG. 3, the power cord 120 of the PDU 100 is located on a top surface 132 of the PDU 100. Power cord 120 can be coupled to a mains power supply (e.g., alternating current (AC) electric power supply, or primary power supply) or a backup (or secondary) power supply such as a UPS. In other examples, the power cord 120 of the PDU 100 can be located at a bottom surface of the PDU 100.

[0022] FIG. 4 is a perspective view of an example PDU, including receptacles on the front and back surfaces, mounted on a rack. As used herein, a rack is a frame used to mount various computing devices such as servers, switches, routers, etc. The rack may include rack columns located at the four corners of the rack where openings may separate the rack columns. The insertion of side panels in the openings between the rack columns may convert the rack into a rack enclosure.

[0023] In the example of FIG. 4, rack enclosure 200 can include a rack 202 and a PDU 100 mounted onto a vertical rack column 114 of the rack 202 via mounting features 104. Mounting features 104 can be an opening, a recess, or a cavity on the vertical rack column 114 of the rack 202. Accordingly, the mounting buttons 102 of the PDU 100 can engage with the mounting features 104 to vertically mount the PDU 100 onto the rack 202.

[0024] As shown in FIG. 4, the PDU 100 is mounted on the top part of one of the two rear (or back) vertical rack columns 114 of the rack 202. In other examples, the PDU 100 can be mounted on the top or bottom of another of the two rear vertical rack columns 114 of the rack 202. PDU 100 includes receptacles 106 on the front surface 116 and on the back surface 126 of the PDU 100. In the example of FIG. 4, the PDU 100 is mounted on its right side 122 such that the body of the PDU 100, including the receptacles 106 and the breaker box 108 and circuit breakers 118, is out of the serviceability area of the rack 202.

[0025] FIG. 5 is a perspective view of an example PDU, including receptacles on the front and back surfaces, mounted on a rack. In the example of FIG. 5, PDU 100 is mounted in the top portion of the rear vertical column 114 of the rack 202. PDU 100 includes receptacles 106 on the front surface 116 and on the back surface 126 of the PDU 100. In this example, PDU 100 is mounted on its left side 112 such that the body of the PDU 100, including the receptacles 106 and the breaker box 108 and circuit breakers 118, is out of the serviceability area of the rack 202.

[0026] FIG. 6 is a perspective view of an example first and second PDU, both including receptacles on the front and back surfaces, and both mounted on a rack. In the example of FIG. 6, two PDUs 100 are mounted in the vertical rack columns 114 of the rack 202. In particular, one PDU 100 is mounted in the top portion of the left rear vertical column 114 of the rack 202, and another PDU 100 is mounted in the bottom portion of the right rear vertical column 114 of the rack 202. Each PDU 100 includes receptacles on the front surface 116 and the back surface 126 of the PDU 100.