scope:

This part of IEC 62055 specifies a physical layer protocol of the STS for transferring units of credit and other management information between a client (typically a HHU) and a server (an STS-compliant electricity payment meter), typically over a direct local connection. It is complementary to the application layer protocol specified in IEC 62055-41 and should be used in conjunction with that standard. This standard is not applicable to payment metering systems employing monetary-based tokens, complex tariffs and currency-mode accounting functions. It is only intended to support the STS functionality as defined in IEC 62055-41 and it does not support the additional functionality required for extended use that includes monetary-based tokens and complex meter functions such as tariffs, real time clocks and currency-mode accounting. If such extended use were required in the future, then it would need new work on this part of IEC 62055 as well as on IEC 62055-41. It is intended for use across a range of payment meters developed by different manufacturers and to ensure compatibility between these products and other client devices. It specifies a client/server communications protocol that: - transfers STS-compliant tokens from a client device to a payment meter server; - reads the result from the payment meter after transfer and execution of the token; - transfers management data from the client device to the payment meter server; - reads management data from the payment meter server and transfers same to the client device.