Articles on: Eastron

Decoding data from the Eastron SDM530-LoRa

Identifying your meter

The Eastron SDM530-LoRa is a three-phase DIN rail mounted electricity meter that communicates over LoRaWAN. As illustrated by the image (left) below it will say SDM530-LR directly to the right of the Eastron logo. The Serial Number (SN) is located on top, above the display as displayed in the image (right).

Eastron SDM530-LoRa

Connecting your meter to a LoRaWAN Network Server

The SDM530-LoRa can be connected to any LoRaWAN Network Server (LNS) including TTN, TTI, Chirpstack and Loriot amongst others. cThings Cloud provide an end-to-end in-built LNS with pre-configured decoders to facilitate connecting the SDM530-LoRa to your existing system. Contact us to find out more.

The SDM530-LoRa must be setup as a Class-C device

Decoding the default data received from the SDM530-LoRa

All SDM530-LoRa meters come with a default configuration pre-installed. If a custom configuration has been requested, see the section below on custom configurations.

By default, data will be sent from the SDM530-LoRa every 30 minutes. Below is an example hex encoded payload that could be sent from a default configured meter (it has been conveniently separated into chunks to match the decode in the table below).

001435FC 01 14 443A424E 42480000 432F0000 00000000 42C5DA1D C591

The meter will send the data in a single payload with the 5 default parameters. The below table shows how to decode the payload and parameters.

Byte RangeDescriptionData TypeExample HexDecoded
0-3Serial NumberUINT32001435FC01324540
4Message Fragment Number (always 1 for default configuration)UINT8011
5Number of Parameter Bytes in this Payload (always 20 for default configuration)UINT81420
6-9Total kWhFLOAT443A424E745.036
10-13DI-1 CountFLOAT4248000050
14-17DI-2 CountFLOAT432F0000175
18-21Relay State-00000000All Relays Open
22-25Total Power FactorFLOAT42C5DA1D98.926
26-27Modbus Checksum-C591-

Custom Configurations

Your SDM530-LoRa may have been configured to send different parameters in a different order. If this is the case, you should have received more information about your custom configuration when you ordered your meter.

Advanced Decoding

Decoding the Relay State

The first three bytes of the Relay State represent the state of each Relay (Phase 1, Phase 2 and Phase 3 respectively). 0x00 indicates the relay is Open and 0xFF indicates the relay is Closed. The below table provides examples of different relay states.

Example HexRelay Phase 1Relay Phase 2Relay Phase 3


By default, the SDM530-LoRa will send 5 parameters in a single payload (one message fragment). For non-standard configurations more parameters may be sent in which case the payload may be fragmented across multiple LoRaWAN payloads. Each parameter will always be 4 bytes in length, starting from byte 6 (0-based) and the final 2 bytes of the message will always be a 2 byte Modbus Checksum.

001435FC 01 18 443A424E 42480000 432F0000 185B
001435FC 02 18 00000000 42C5DA1D 00000000 D821

Updated on: 05/06/2023

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