The GS1 system gives each electricity installation a unique identifier. In addition, this identifier can be rapidly and reliably read from a bar code.
Unique installation identifiers using the GS1 system
Installations (metering points) are identified using a GSRN (Global Service Relation Number) which is 18 digits long and consists of a GS1 company prefix, a sequence number, and a check digit. Each company prefix allows for 100 million unique installation identifiers.
GS1 has issued a GS1 company prefix to Swedish network companies which includes a common industry number. This allows a shorter number for the installation identity (metering points) to be used in spoken communication. A network company has the company prefix 735999XXX, where XXX is unique for the company. The network company then numbers its own installations.
Structure of an installation identifier
Installation identifier: 735999XXXAAAAAAAAK
735999XXX = GS1 company prefix
A...A = sequence number
K = check digit
Rules in the event of sale or transfer
Installations retain their identity even if the ownership of the installation is transferred to another company. If a network company sells part of its network, and that's a number of installations, the installations retain their identity in the sold network. If a network company ceases to trade and is completely transferred to another company then the company prefix should be transferred to the new owner.
Marking an installation with a barcode
The bar code symbology GS1-128 is used for installation identifiers. This code consists of bar code symbology Code 128 with function code 1 (FNC one) followed by one or more data elements, in this case the installation identifier. Each data element starts with an application identifier (AI).
Application identifiers are used by the bar code reader to identify the data element type and to correctly process the information in a business system. The AI for GSRN, installation identifier, is 8018. Both the AI and the installation identifier are included in the bar code and the digits are printed beneath the bar code with the AI in parentheses.
Installation identifiers in databases
Note that the digits for the AI (in this case 8018) should not be stored in databases together with the installation identifier. Neither are they included in the calculation of the check digit.
All 18 digits of an installation identifier must be stored in a database even if part of the company prefix is a common number.