A Python library for DLMS/COSEM.

Installation

pip install dlms-cosem

Documentation

Full documentation can be found at www.dlms.dev

About

dlms-cosem is designed to be a tool with a simple API for working with DLMS/COSEM enabled energy meters. It provides the lowest level function, as protocol state management, APDU encoding/decoding, APDU encryption/decryption.

The library aims to provide a sans-io implementation of the DLMS/COSEM protocol so that the protocol code can be reused with several io-paradigms. As of now we provide a simple client implementation based on blocking I/O. This can be used over either a serial interface with HDLC or over TCP.

We have not implemented full support to be able to build a server (meter) emulator. If this is a use-case you need, consider sponsoring the development and contact us.

Supported features

• AssociationRequest and AssociationRelease
• GET, GET.WITH_BLOCK, GET.WITH_LIST
• SET
• ACTION
• DataNotification
• GlobalCiphering - Authenticated and Encrypted.
• HLS-GMAC, LLS, HLS-Common auth
• Selective access via RangeDescriptor
• Parsing of ProfileGeneric buffers

Example use:

A simple example of reading invocation counters using a public client:

from dlms_cosem.client import DlmsClient
from dlms_cosem.io import TcpTransport, BlockingTcpIO
from dlms_cosem.security import NoSecurityAuthentication
from dlms_cosem import enumerations, cosem

tcp_io = BlockingTcpIO(host="localhost", port=4059)
tcp_transport = TcpTransport(io=tcp_io, server_logical_address=1, client_logical_address=16)
client = DlmsClient(transport=tcp_transport, authentication=NoSecurityAuthentication())
with client.session() as dlms_client:
    data = dlms_client.get(
        cosem.CosemAttribute(interface=enumerations.CosemInterface.DATA,
                             instance=cosem.Obis(0, 0, 0x2B, 1, 0), attribute=2, ))

Look at the different files in the examples folder get a better feel on how to fully use the library.

Supported meters

Technically we aim to support any DLMS enabled meter. The library is implementing all the low level DLMS, and you might need an abstraction layer to support everything in your meter.

DLMS/COSEM specifies many ways of performing tasks on a meter. It is customary that a meter also adheres to a companion standard. In the companion standard it is defined exactly how certain use-cases are to be performed and how data is modeled.

Examples of companion standards are:

• DSMR (Netherlands)
• IDIS (all Europe)
• UNI/TS 11291 (Italy)

On top of it all your DSO (Distribution Service Operator) might have ordered their meters with extra functionality or reduced functionality from one of the companion standards.

We have some meters we have run tests on or know the library is used for in production

• Pietro Fiorentini RSE 1,2 LA N1. Italian gas meter
• Iskraemeco AM550. IDIS compliant electricity meter.
• Itron SL7000
• Hexing HXF300

License

The dlms-cosem library is released under the Business Source License 1.1 . It is not a fully Open Source License but will eventually be made available under an Open Source License (Apache License, Version 2.0), as stated in the license document.

Our goal with this licence is to provide enough freedom for you to use and learn from the software without harmful free-riding.

You may make use of the Licensed Work for any Permitted Purpose other than a Competing Use. A Competing Use means use of the Licensed Work in or for a commercial product or service that competes with the Licensed Work or any other product or service we offer using the Licensed Work as of the date we make the Software available.

Competing Uses specifically include using the Licensed Work:

1. as a substitute for any of our products or services;

2. in a way that exposes the APIs of the Licensed Work; and

3. in a product or service that offers the same or substantially similar functionality to the Licensed Work.

Permitted Purposes specifically include using the Software:

1. for your internal use and access;

2. for non-commercial education; and

3. for non-commercial research.

For information about alternative licensing arrangements or questions about permitted use of the library, please contact us at info(at)pwit.se.

Development

This library is developed by Palmlund Wahlgren Innovative Technology AB. We are based in Sweden and are members of the DLMS User Association.

If you find a bug please raise an issue on Github.

We add features depending on our own, and our clients use cases. If you need a feature implemented please contact us.

Training / Consultancy / Commercial Support / Services

We offer consultancy service and training services around this library and general DLMS/COSEM. If you are interested in our services just reach at ìnfo(at)pwit.se

The library is an important part of our Smart meter platform Utilitarian, https://utilitarian.io. If you need to collect data from a lot of DLMS devices or meters, deploying Utilitarian might be the smoothest solution for you.