Readout To Dlms - Landis+Gyr E650 Series 4 User Manual

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5.7.2

Readout to DLMS

DLMS specification
Objective
Principle
DLMS items
© Landis+Gyr
While the readout according to IEC 62056-21 uses a predefined protocol,
readout to DLMS enables the power supply company to read out values
individually. The company therefore has systematic access to specific
values without being influenced by other values that are not required.
Various meter manufacturers – including Landis+Gyr – together with
related organisations, have compiled the language specification DLMS
(Device Language Message Specification).
The objective of DLMS is to use a common language for data exchange in
energy measurement and other sectors. In addition to end units such as
meters, tariff units, etc. DLMS also defines the interfaces, transmission
channels and system software.
DLMS delivery oriented protocol can be compared to sending a letter: the
sender writes the address of the recipient on the letter and hands it to the
post office for transport. The way in which the postal department transports
the letter is of no consequence to the sender and receiver. The only
important thing is that the address of the recipient is clearly shown and that
the letter is received, read and it can be seen from whom the letter
originates.
Units with DLMS operate in a similar way. They provide the values –
termed objects – required by the receiver (e.g. control centre) and pass
them via interface to the transport medium (channel). How the values reach
the recipient is again immaterial for both parties.
DLMS is an object-oriented language. The DLMS objects

have an unique name in the form of the EDIS identification number

contain the value in an exactly defined form and

are configured in a similarly exactly defined format.
Examples are number of resets with date and time, cumulative maxima,
rolling mean values, maxima, energy status, associated stored values, etc.
The sender feeds these objects to a transport medium, e.g. the telephone
network. This transmits them to the receiver, so that the objects are
received in the same form as supplied by the sender.
D000062026 en a – E650 Series 4 – ZMD400AT/CT, ZFD400AT/CT – User Manual
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