WO2017137267A1

WO2017137267A1 - Automatically deducing the electrical cabling between electrical devices

Info

Publication number: WO2017137267A1
Application number: PCT/EP2017/051784
Authority: WO
Inventors: Laurent Lefebvre
Original assignee: Eaton Industries (France) Sas
Priority date: 2016-02-09
Filing date: 2017-01-27
Publication date: 2017-08-17
Also published as: GB201602327D0

Abstract

The invention relates to a system (100) for automatically deducing the electrical cabling between electrical devices, comprising at least one electrical cable (106) comprising a plug (110) and an electronic device (112) storing an identification of a first electrical device, wherein the plug comprises first electric contacts, and wherein second electric contacts (114) are provided for access to the stored identification, a second electrical device (104) comprising at least one socket for the plug of the at least one electrical cable, wherein the socket comprises first electric contacts for contacting the first electric contacts of the plug, and second electric contacts for contacting the second electric contacts of the plug, and a cabling management system (118+120) configured to electronically obtain the identification of the first electrical device stored in the electronic device of the at least one electrical cable, the plug of which is connected to the at least one socket of the second electrical device, and to deduce the electrical cabling between the electrical devices from the electronically obtained identification.

Description

DESCRIPTION

TITLE

Automatically deducing the electrical cabling between electrical devices

TECHNICAL FIELD

The invention relates to automatically deducing the electrical cabling between electrical devices, particularly the cabling between a primary power source and endpoints in datacenters.

BACKGROUND

In datacenters with racks having many electrical devices such as IT (Information Technology) devices like servers, computers, routers, switches, storage units, etc., the electrical cabling topology comprising links between the primary power source, for example an Uninterruptible Power Supply (UPS) or Power Distribution Unit (PDU) or Automatic or Static Transfer Switch (ATS, STS), and end-points, their Power Supply Units (PSU) or network switches, is difficult and expensive to identify and to maintain. This is primarily due to the usually large amount of cables accumulated behind racks. Cables are often similar, for example having the same color, the same section, etc... Thus, it is difficult for technicians to differentiate the cables.

Technicians can verify links behind a rack manually for example by noting the chosen plug identifier (something like the PDU name and outlet number), by following the electrical cable, starting from the previously chosen outlet to its other side, which can, however, be difficult due to number of cables and knots, cable access (cable hidden under the floor or over the rack's top), and cable sizes, or by noting the power consumer at the other side of the cable. Solutions to make the cabling easier are known in the art: US patent US5,666,453 relates to a fiber optic jumper cables and a tracing method using the same. US patent US6,906,505B2 and the European patent EP2083487B1 describe methods and devices for visually identifying cables by means of light signals transmitted via optical fibers disposed on a cable and extending from a first end to a second end of the cable.

However, the manual process of deducing the electrical cabling between devices is often time consuming and error prone. Wrong outlet disconnection or outlet number manual entry errors can lead to unwanted downtime. Using IT device's PSU monitoring information from the network, for instance from IPMI (Intelligent Platform Management Interface) tools, to get PSU power status can help in a few cases but cannot solve all the cabling errors situations. For instance, if a server's dual PSUs are connected on the same PDU, the redundancy of power supplies is lost, which compromises the availability of the server or can cause unexpected overload of the PDU, providing downtime of connected devices. Calculation of power capacity or headroom, automatic start-up/ shutdown sequence of IT devices connected to PDUs, can also fail from these manual entry errors. Such errors can occur regularly in a short period of time where an IT device can be moved or retired, and where new IT devices can be added within a datacenter.

The US patent application US2013/0164971A 1 is related to smart power monitoring technology and provides a smart socket, which comprises a set of power sockets, configured for a set of power pins of a smart plug to plug into, a driving pin and a set of detection pins, configured for forming a circuit with a set of feedback pins of a smart plug when the set of power pins is plugged into the power sockets, and an identification code module, configured for obtaining an identification code of an electric appliance, from the circuit, to which the smart plug belongs. Also a smart plug is provided, which comprises a set of power pins, for plugging into a set of power sockets of a smart socket; and a set of feedback pins, configured for forming a circuit with a driving pin and a set of detection pins of a smart socket when the set of power pins and the set of power sockets are connected to each other. Furthermore, a smart adaptor is provided, which comprises a set of adapting pins, configured for a set of power pins of a normal plugs to plug into, and for adapting the set of power pins to a set of power sockets of a smart socket; and a set of feedback pins, configured for forming a circuit with a driving pin and a set of detection pins of the smart socket when the power pins and the power sockets are connected to each other.

SUMMARY OF INVENTION

It is an object of the present invention to propose a technical solution, which makes it further easier for technicians to verify the electrical cabling between electrical devices, in order to reduce or eliminate the power outages and downtime of connected electrical devices due to cabling error.

This object is achieved by the subject matter of the independent claims. Further embodiments are shown by the dependent claims. The present invention is based on the idea to provide an electronic device in an electrical cable for cabling a first and a second electrical device such as a power cable for cabling the PSU of an IT device with the power outlet of a PDU, wherein the electronic device stores an identification of the first device, which can be accessed via electric contacts provided on the end of the cable, which is plugged into a socket of the second electrical device. The stored information can then be obtained by cabling management system, which can deduce the electrical cabling between electrical devices, for example to which power outlet socket the first electrical device is cabled. The invention can replace the manual process of deducing the electrical cabling between electrical devices by an automatic process, and can significantly reduce the manual effort time and errors. The invention allows automatic and real time detection and association of an electrical device such as an IT device and its cabling, for example its power source within a datacenter.

An embodiment of the invention relates to a system for automatically deducing the electrical cabling between electrical devices, comprising at least one electrical cable comprising a plug and an electronic device storing an identification of a first electrical device, wherein the plug comprises first electric contacts, and wherein second electric contacts are provided for access to the stored identification, a second electrical device comprising at least one socket for the plug of the at least one electrical cable, wherein the socket comprises first electric contacts for contacting the first electric contacts of the plug, and second electric contacts for contacting the second electric contacts of the plug, and a cabling management system configured to electronically obtain the identification of the first electrical device stored in the electronic device of the at least one electrical cable, the plug of which is connected to the at least one socket of the second electrical device, and to deduce the electrical cabling between the electrical devices from the electronically obtained identification.

The cabling management system may be configured to monitor each socket of the second electrical device for plugged in electrical cables, to obtain identifications of the first electrical devices stored in the electronic devices of the plugged in electrical cables, and to assign the obtained identifications to the sockets of the second electrical device.

The cabling management system may comprise a controller being configured to monitor a socket of the second electrical device for a plugged in electrical cable by selecting one of several sockets of the second electrical device, checking whether an electronic device can be accessed via the second contacts, and reading an identification of a first electrical device from the electronic device if accessible.

An embodiment of the cabling management system where electronic device can be accessed via the second contacts by the controller, relates to the use of a serial bus which may be I2C, 1-wire, USB (Universal Serial Bus), SPI (Serial Peripheral Interface), RS232, RS485.

The controller may be configured to sequentially monitor each socket of the second electrical device for a plugged in electrical cable and to output data regarding identifications of first electrical device and their assignments to the respective sockets.

The output data regarding identifications of first electrical device and their assignments to the respective sockets of a second device can be sent to a host computer (via a network or wireless interface) being configured by a host software to process the received output data, particularly to store the received output data, to manage the power cabling depending on the received output data, particularly to raise alerts, to display information on the connection and/or power status depending on the received output data (to manage (display, generate alarms from) the deduced electrical cabling between the electrical devices, their connections status or power status).

The cabling management system may be configured to perform one or more of the following tasks: visually representing the deduced electrical cabling between the electrical devices on a local or remote display; sending the data related to the deduced electrical cabling to a host software via a network or wireless interface; managing alerts about connections status or power status of connected devices

The first electrical device may be an IT device and the second electrical device may be a power supply device, particularly an Uninterruptible Power Supply, a Power Distribution Unit or an Automatic or Static Transfer Switch. Alternatively, the first electrical device and the second electrical device may be power supply devices, particularly an Uninterruptible Power Supply, a Power Distribution Unit or an Automatic or Static Transfer Switch. A further embodiment of the invention relates to an electrical cable configured for application with a system of the invention and as described herein, wherein the cable comprises plugs on both ends of the cable, one or more electrical wires extending from one plug to the other plug of the cable and being connected to first electric contacts of the plugs, an electronic device provided for storing an identification of a first electrical device, and second electric contacts provided in at least one of the plugs for access to the stored identification.

The electronic device may be a programmable read-only memory, particularly an erasable programmable read-only memory.

The electronic device may be located directly under the second electric contacts, particularly the electronic device may be comprised together with the second electric contacts in a 1 -wire-contact package.

The one or more electrical wires extending from one plug to the other plug of the cable and being connected to first electric contacts of the plugs may be provided for power supply.

A yet further embodiment of the invention relates to an attachment of the cable of the invention and as described herein to the first electrical device for making a semi- permanent link between the first electrical device and the cable, wherein the attachment comprises a sticker pad coupled with the first electrical device and a cable tie attaching the cable to the sticker pad and/or a cable tie for attaching the electrical cable to a strain relief of the first electrical device.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

The invention will be described in more detail hereinafter with reference to exemplary embodiments. However, the invention is not limited to these exemplary embodiments.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 shows a general embodiment of the system for automatically deducing the electrical cabling between an IT device and a power device according to the invention;

Fig. 2 shows an embodiment of the system for automatically deducing the electrical cabling between dual supply IT devices, PDU and UPS according to the invention;

Fig. 3 shows an embodiment of the system for automatically deducing the electrical cabling between single supply IT devices, PDU, ATS and UPS according to the invention; Fig. 4 shows an embodiment of the system using the I2C bus, for automatically deducing the electrical cabling between electrical devices according to the invention

Fig. 5 shows a flow chart of an algorithm using the I2C bus for automatically deducing the electrical cabling between electrical devices performed by the system of Fig. 4 according to the invention; Fig. 6 shows an embodiment of the system using the 1-wire bus, for automatically deducing the electrical cabling between electrical devices according to the invention;

Fig. 7 shows a flow chart of an algorithm using the 1-wire bus for automatically deducing the electrical cabling between electrical devices performed by the system of Fig. 6 according to the invention;

Fig. 8 shows an embodiment of an attachment between the IT device and the special cord; and

Fig. 9 to 11 show different embodiments of IEC standardized plugs and sockets according to the invention.

DESCRIPTION OF EMBODIMENTS

In the following, functionally similar or identical elements may have the same reference numerals. Absolute values are shown below by way of example only and should not be construed as limiting the invention.

Embodiments of the present invention provided for application in datacenters, where the PSUs of IT devices are cabled with a PDU are now described. However, the present invention is not limited to this application, but can be applied to deduce any cabling between electrical devices, not only power cabling.

The embodiments described in the following are implemented for automatically detecting the connection of the power cord of an IT device (server, computer, router, switch, storage unit ...) to a PDU outlet. As soon as the power cord is connected, the described embodiments of the inventive system automatically identify which IT device is connected to which PDU outlet. By extension, if the PDU is connected to an UPS or ATS, it can also automatically identify which PDU is connected to which UPS or ATS. It can make real time associations of the cabling (unique IT device ID, PDU outlet number, PDU ID, UPS ID, ATS ID) and finally report this information via a network to a remote monitoring SW application. Integrated inside a PDU, UPS or ATS, the inventive system can provide the capability for a remote SW application to automatically identify the full power topology and power connection status of all IT devices within a datacenter.

Fig. 1 shows a general embodiment of the system 100 for automatically deducing the electrical cabling between an IT device 102 and a power device 104 according to the invention. A special power cord or cable 106 is used for supplying electric power from the power device 104 to the IT device 102. The cable 106 is similar to a standard power cable used for supplying IT devices and comprises on one end a standard plug 108 for plugging into a socket of for example the PSU A of the IT device 102. On the other end, the cable 106 comprises a special plug 110, which corresponds to the standard plug 108 in its dimensions and shape so that it can be plugged into to a corresponding socket such as a power outlet socket of the power device 104. In the special plug 110, an electronic device 112 storing an ID of the IT device 102 is integrated. The electronic device 112 can be implemented as E2PROM device. The device 112 comprises an interface for accessing the IT device's ID stored therein. Access to the stored IT device's ID is provided via dedicated contact pins 114, which are integrated in the plug 110 in addition to and separated from power supply pins. The contact pins 114 could also be provided in a separate plug to be connected to a respective separate socket of the power device 104.

The power device 104 comprises, as an example, four special power outlet sockets #1 to #4, however in this invention, the socket number is not limited. These sockets #1 to #4 comprise in addition to the power supply pins also dedicated contact pins 116 to be contacted with the pins 114 of the special plug 110. The power device 104 additionally comprises a hardware for cabling identification, which comprises a controller 118, an identification reader system 120, and a network interface 122 for transmitting and receiving data over a wired and/or wireless network. The devices 118, 120, 122 are wired as shown in Fig.l. The controller 118 is configured by a firmware to execute an algorithm for monitoring the power outlet sockets #1 to #4 in order to automatically deduce the electrical cabling between IT devices 102 and the power device 104. The identification reader system 120 generates with deduced and identified electrical cabling such as the cabling between the PSU A of IT device 102 and power outlet socket #2 of the power device 104, an identification table assigning IT device IDs to power outlet socket nos. This table can be read by the controller 118 and transmitted via the network interface 122 to a host computer 124, which stores the identification table and can perform different tasks such as displaying and managing the power cabling, the connection status, raise connection alarms, display the power status, and raise power alarms.

The controller 118 can also control the power cabling system 126 of the power device 104 via a power management system 128, for example control the power supply of the power outlet sockets #1 to #4.

The power device 104 can comprise its own special power cord cable 130 having a special plug to be plugged into the outlet socket of a power source in order to supply the power device 104 with electrical energy. The power device ID is then stored in the electronic device (E2PROM) of the special plug.

Fig. 2 shows the application of the inventive system for automatically deducing the electrical cabling between dual supply IT devices, PDU and UPS and Fig. 3 shows the application of the inventive system for automatically deducing the electrical cabling between single supply IT devices, PDU, ATS and UPS.

Fig. 4 shows now an embodiment of a system 10 for the automatic deduction of the electrical cabling between IT devices and a PDU in a datacenter, which applies an I2C serial data bus. A special power cord or cable 12 is used for supplying electric power from a PDU 20 to an IT device (not shown). The cable 12 is similar to a standard power cable used for supplying IT devices and comprises a power cord plug 14 with power supply pins on its end, which is connected to a power outlet socket of the PDU. Additionally, the cable 12 comprises an E2PROM device 16, which can be integrated in or attached to the cable jacket of the plug 14. The E2PROM device 16 comprises an I2C bus interface, which is connected to several E2PROM access contacts 18, which can be integrated in the plug 14 in addition to the power supply pins (but separated from these pins) or in a separate plug to be connected to a respective separate socket of the PDU. The E2PROM device 16 stores an identification of the IT device, with which the cable 12 is connected, for example a server ID number. This identification can be read out via the plug 14, which allows accessing the E2PROM device 16 via the I2C bus protocol.

In this example, the PDU 20 comprises two blocks each having 8 power outlet sockets: the first block has power outlet sockets 22 (#1 to #8), and the second block has power outlet sockets 24 (#9 to #16). The PDU 20 additionally comprises a hardware 26 for cabling identification, which comprises a controller 28 with an I2C bus interface, three multiplexer circuits 30, 32, and 34, and a network interface 36 for transmitting and receiving data over a computer network like a LAN (Local Area Network). The devices 28, 30, 32, and 34 are wired as shown in Fig. 4. The controller 28 is configured by a firmware to execute an algorithm for monitoring the power outlet sockets 22 and 24 in order to automatically deduce the electrical cabling between IT devices and the PDU 20. The flowchart of the algorithm is shown in Fig. 5.

As shown in Fig. 4, an IT device is connected with the special power cord 12 to the power outlet socket #10 of the first block of power outlet sockets 22. The E2PROM device 16 stores an identification of the IT device. Further, the I2C bus interface of the E2PROM device 16 is connected via the plug 18 to the I2C bus interface of the power outlet socket #10. For automatically detecting the cabling between the IT device and the power outlet socket #10, the algorithm performed by controller 28 sequentially scans the power outlets 22 and 24 by obtaining the identifications stored in E2PROM devices 16 of cables 12 connecting IT devices with the power outlets 22 and 24. The steps of the algorithm performed by the controller 28 are shown in the flowchart of Fig. 5: in a first step, the controller 28 sets an outlet number #OutNb to 1, and then sends in a second step an I2C write commands to the multiplexers 30, 32, 34 in order to connect the I2C interface of the controller 28 to the set outlet number #OutNb. In a third step, the controller 28 sends an I2C read command to the generic e2prom I2C address through the selected power outlet via the path switched by the multiplexer's. In a fourth step, the controller 28 waits if an E2PROM responds with an Ack reply to the read command (which is the case if a cable 12 is connected with the selected power outlet socket). If the controller 28 receives an Ack reply, it also receives in a fifth step the data of the I2C read command which contains the IT device ID from the E2PROM device 16. The controller 28 stores in a sixth step the obtained IT device ID in an internal table comprising associations [outlet number, It device ID]. If the controller 28 does not receive an Ack reply to its read command, it continues with a seventh step, where it checks whether the maximum number of power outlet sockets is reached by comparing the outlet number OutNb# with the maximum number. The seventh step is also preformed after the update of the internal table in the sixth step. If the maximum number is not reached, the controller 28 increases in an eighth step the outlet number OutNb# by 1 and steps back to the second step in order to scan the next power outlet socket. If the maximum number is reached, the controller 28 sends in a ninth step the internal table with the associations [outlet number, It device ID] over the network interface 36 to a computer for further processing, particularly for visualizing the deduced cabling. Thus, each power outlet socket is scanned and a table with associations [outlet number, It device ID] is generated for all power outlet sockets of the PDU.

Fig. 6 shows an embodiment of a system 11 for the automatic deduction of the electrical cabling between IT devices and a PDU in a datacenter, which applies a 1-wire bus instead of a 2-wire I2C bus. In the following, only the differences between the first and second embodiment are described. The cable 13 of the second embodiment comprises a 1-wire E2PROM device 17 and, thus, only one E2PROM access contact 19 may be provided for access to the information stored in the device 17. A first block of power outlet sockets 23 (#1 to #8) and a second block with power outlet sockets 24 (#9 to #16) are provided, wherein for each power outlet socket a respective single contact for contacting with the E2PROM access contact 19 is provided. The controller 29 comprises a 1-wire interface for access to the devices 17 in the cables 13 connected to power outlet sockets 23 and 25 via access contacts 19. The 1-wire interface of controller 29 is connected to an 8-channel GPIO device 37 for controlling three multiplexers 31, 33, and 35 and the switching of the path from the 1-wire interface to one of the power outlet sockets 23, 25. The 1-wire interface of controller 29 is also connected to the input of the first multiplexer 31. The controller 29 is configured by a firmware to execute an algorithm for monitoring the power outlet sockets 23 and 25 in order to automatically deduce the electrical cabling between IT devices and the PDU 21. The flowchart of the algorithm is shown in Fig. 6. Principally, the flowchart of this algorithm is similar to the one shown in Fig. 5 with a slight difference due to the 1-wire protocol as outlined in Fig. 7.

Fig. 8 shows an attachment between the IT device 102 and the special cord 106 in order to avoid that the identification of the IT device stored in the electronic device of the special cord is not easily separated from the IT device. For IT devices with standard PSU, an additional flat pad 132 may be sticked on top of device 102, from which a cable tie is used to attach special cord to the IT device, as shown left in Fig. 8. For IT devices 102 with PSU having strain relief 134, a cable tie can be used to attach the special cord 106 to the IT device 102 to the strain relief . A double cable tie 136 can be used for instance for a better fastening.

The power outlet socket scan as described above can be performed regularly, periodically, automatically, or manually (for example initiated by a technician).

Fig. 9 shows two implementations of an IEC 14 plug and an IEC 13 socket, respectively. Both IEC 14 plug implementations comprise an E2PROM 1-wire-contact package (SFN package), which is located on the plug's outside (left plug picture) or on the plug's inside (right plug picture). The E2PROM SFN package comprises contacts for accessing the identification stored in the E2PROM. The E2PROM itself is located directly under the contacts so that no dedicated wiring is required within the plug. The respective IEC 13 sockets comprise (standard or custom) contacts for contacting the corresponding E2PROM access contacts of the IEC14 plug, as shown in Fig. 9. Fig. 10 shows an implementation of a IEC13 socket group comprising 4 sockets, each being equipped with (standard or custom) contacts for contacting the corresponding E2PROM access contacts of the IEC14 plug (shown above left in Fig. 9). The IEC13 socket group further comprises a PCB (Printed Circuit Board) with a small signal connector wiring its contact with the (standard or custom) contacts. Fig. 11 shows an implementation of an IEC20 plug comprising an E2PROM SFN package and a corresponding IEC 19 socket with (standard or custom) contacts for contacting the corresponding E2PROM access contacts of the IEC20 plug. The present invention is particularly suitable for application in datacenters in order to automate the discovery and maintaining of power links (power topology) and can help technicians to save time required for cabling.

REFERENCE NUMERALS AND ABBREVIATIONS

10 Automatic cabling identification system based on 2-wire I2C bus protocol

11 Automatic cabling identification system based on 1-wire protocol

12 Special power cord/cable

13 Special power cord/cable

14 Special Power cord plug

16 I2C E2PROM storing device ID

17 1-wire E2PROM storing device ID

18 I2C E2PROM access contacts

19 1-wire E2PROM access contacts

20 PDU with 16 power outlet sockets

21 PDU with 16 power outlet sockets

22 Power outlet sockets #l-#8

23 Power outlet sockets #l-#8

24 Power outlet sockets #9-#16

25 Power outlet sockets #9-#16

26 Hardware for cabling identification based on I2C bus protocol

27 Hardware for cabling identification based on 1-wire protocol

28 Controller with I2C interface

29 Controller with 1-wire interface

30 I2C Multiplexer #0

31 Analog Multiplexer #0

32 I2C Multiplexer #1

33 Analog Multiplexer #1

34 I2C Multiplexer #2

35 Analog Multiplexer #2

36 Network interface

37 8-channel GPIO device

100 Automatic cabling identification system

102 IT device with dual PSU

104 power device with four power outlet sockets 106 special power cable

108 standard plug of special power cable 106

110 special plug of special power cable

112 electronic device (E2PROM) for storing IT device's ID

114 pins in special plug 110 for accessing electronic device 112

116 pin in power outlet socket for contacting with pins 114

118 controller

120 identification reader syste

122 network interface

124 host computer

126 power cabling system

128 power management system

130 special power cable of power device 104

132 sticker pad with IT device's identification number

134 strain relief

ATS Automatic Transfer Switch

E2PROM Electrical Erasable Programmable Read-Only Memory

I2C I²C/I-squared-C serial bus invented by Philips Semiconductor

1-wire 1-wire serial bus invented by Dallas Semiconductor.

ID Identification

IPMI Intelligent Platform Management Interface

IT Information Technology

LAN Local Area Network

GPIO General Purpose Input/Output

PCB Printed Circuit Board

PDU Power Distribution Unit

PSU Power Supply Unit

SPI Serial Peripheral Interface

STS Static Transfer Switch

UPS Uninterruptible Power Supply

USB Universal Serial Bus

Claims

1. System (100) for automatically deducing the electrical cabling between electrical devices (102, 104), comprising at least one electrical cable (106) comprising a plug (110) and an electronic device (112) storing an identification of a first electrical device (102), wherein the plug comprises first electric contacts, and wherein second electric contacts (114) are provided for access to the stored identification, a second electrical device (104) comprising at least one socket for the plug of the at least one electrical cable, wherein the socket comprises first electric contacts for contacting the first electric contacts of the plug, and second electric contacts (116) for contacting the second electric contacts (114) of the plug, and a cabling management system (118, 120) configured to electronically obtain the identification of the first electrical device stored in the electronic device of the at least one electrical cable, the plug of which is connected to the at least one socket of the second electrical device, and to deduce the electrical cabling between the electrical devices from the electronically obtained identification.

2. The system of claim 1, wherein the cabling management (118, 120) system is

configured to monitor each socket of the second electrical device for plugged in electrical cables, to obtain identifications of the first electrical devices stored in the electronic devices of the plugged in electrical cables, and to assign the obtained identifications to the sockets of the second electrical device.

3. The system of claim 1 or 2, wherein the cabling management system (118, 120)

comprises a controller (118) being configured to monitor a socket of the second electrical device for a plugged in electrical cable by selecting one of several sockets of the second electrical device, checking whether an electronic device can be accessed via the second contacts, and reading an identification of a first electrical device from the electronic device if accessible.

4. The system of claim 3, wherein the controller (118) is configured to sequentially monitor each socket of the second electrical device for a plugged in electrical cable and to output data regarding identifications of first electrical device and their assignments to the respective sockets.

5. The system of claim 4, wherein the output data regarding identifications of first electrical device and their assignments to the respective sockets of a second device are sent to a host computer (124) being configured by a host software to process the received output data, particularly to store the received output data, to manage the power cabling depending on the received output data, particularly to raise alerts, to display information on the connection and/or power status depending on the received output data.

6. The system of any of the preceding claims, wherein the cabling management system is configured to perform one or more of the following tasks: visually representing the deduced electrical cabling between the electrical devices on a local or remote display; sending the data related to the deduced electrical cabling to a host software via a network with wired or wireless interface ; managing alerts about connections status or power status of connected devices.

7. The system of any of the preceding claims, wherein the first electrical device is an information technology device and the second electrical device is a power supply device, particularly an Uninterruptible Power Supply, a Power Distribution Unit or an Automatic or Static Transfer Switch, or the first electrical device and the second electrical device are power supply devices, particularly an Uninterruptible Power Supply, a Power Distribution Unit or an Automatic or Static Transfer Switch.

8. An electrical cable (106) configured for application with a system (100) of any of the preceding claims comprising plugs on both ends of the cable, one or more electrical wires extending from one plug to the other plug of the cable and being connected to first electric contacts of the plugs, an electronic device provided for storing an identification of a first electrical device, and second electric contacts provided in at least one of the plugs for access to the stored identification.

9. The cable of claim 8, wherein the electronic device is programmable read-only

memory, particularly an erasable programmable read-only memory.

10. The cable of claim 8 or 9, wherein the electronic device is located directly under the second electric contacts, particularly the electronic device is comprised together with the second electric contacts in a 1 -wire-contact package.

11. The cable of claim 8, 9 or 10, wherein the one or more electrical wires extending from one plug to the other plug of the cable and being connected to first electric contacts of the plugs are provided for power supply.

12. An attachment of the cable (106) of claim 8, 9, 10 or 11 to the first electrical device (102) for making a semi-permanent link between the first electrical device (102) and the cable (106), wherein the attachment comprises a sticker pad (132) coupled with the first electrical device (102) and a cable tie attaching the cable (106) to the sticker pad (132) and/or a cable tie (136) for attaching the electrical cable (106) to a strain relief (134) of the first electrical device (102).