DLMS protocol for LZQJ-DLMS-E-1.25

[Jellyfish]

Hi,

I have a power meter unit which model is LZQJ-DLMS-E-1.25, I need use labVIEW to communicate with this power meter by using serial protocol. Unfortunately, this power meter doesn't support ModBUS, it is using DLMS protocol which send a HDLC format of HEX command to the power meter to get certain value.

I have no idea on the DLMS portocol, is there anyone familiar with the power meter or anyone know how to use labVIEW to send the command to the power meter ?

I just want the KWH reading from the power meter. Anyone can help me on this or provide the example with the HEX command which able to get KWH reading?

[RameshRManubolu]

Hi,

    first of all to start communication with DLMS protocol meter, u should send SNRM command to set the power meter in "normal response mode" once it ackowledges to this command, we should associate to one of the three associations namely Public client (PC), Meter Reader (MR), Utility setting (US) as later two association requires password try associating with PC (i.e., Public Client).

[Jellyfish]

Hi Ramesh,

Thanks of your reply, so it there any example to show me ? I even the command also don't know what need to send for the DLMS Power Meter. I had search a lot website but still can't understand the command and the step. Can guide me on this ? Thank you very much.

[RameshRManubolu]

hi,

try with the following command

SNRM (set normal response mode) - 0x7E 0xA0 0x07 0x03 0x21 0x93 0x0F 0x01 0x7E

if it response to this try associating with Public client

AARQ (Application association request) - 0x7E 0xA0 0x2B 0x03 0x21 0x10 0xFB 0xAF 0xE6 0xE6 0x00 0x60 0x1D 0xA1 0x09 0x06 0x07 0x60 0x85 0x74 0x05 0x08 0x01 0x01 0xBE 0x10 0x04 0x0E 0x01 0x00 0x00 0x00 0x06 0x5F 0x1F 0x04 0x00 0x00 0x18 0x1D 0xFF 0xFF 0x5F 0xAF 0x7E

all commands are in hexadecimal, 1 byte each.

All the best.

[Jellyfish]

Hi Ramesh,

Thank of your reply. So after these 2 commands give response, then i can send request code of KWH readings from the power meter? 

then can you show me the code to request the KWH readings ? i study severals table about OBIS code but i can't understand what is the code need to send for the KWH readings ?

Can you help me on this. Thank you very much.

[RameshRManubolu]

Hi,

    You need download the object list in order to know the objects present in that particular association. The OBIS code for kWh register depends on respective country standards and i don't think you can read the kWh register in Public client b'coz Public client will have only few objects namely, Logical device name, Meter serial Number, Sap address, association ln object and real time clock (RTC); in order to read kWh need to associate with Meter reader association which requires "Password" .

[Jellyfish]

Hi Ramesh,

So if i get the password, can i access to the power meter to get the KWH readings ?

My suppliers provide me a manual guide which at the attachment. At page 16 is the appendix for the OBIS code and i don't know which one is refer to the KWH readings, my suppliers also don't know about this, can Mr Ramesh show me and also the code that need send to the power meter based on the OBIS code ?

i'm very confuse how to get the code from the OBIS form, can Ramesh guide me some of this. thank you very much.

[RameshRManubolu]

Hi,

    they have given the example of sending command and receiving the response at appendix A2, please read that.

from appendix A1 table i can see from sl no 7 to 53 are energy registers.

    as i haven't worked on Short Name referencing, i can't provide the read command for kWh register i'm sorry helpless in this case. this power meter uses short naming referencing, but i have only worked on Logical naming reference; i need sometime in order to help you in reading kWh register.

[Jellyfish]

Hi Ramesh,

Thank you of your guide. So from the appendix 2 example, i just follow the step to send the data for the power meter ? The command string for SNRM, AARQ & DISC,UA are the same command ? So to communicate with the power meter, my labVIEW need to the following steps: send SNRM code=> verified reply => Send AARQ code => verified reply for AARE => send to request energy code => decode the readings => send DISC code => verified reply, am i right ?

By the way, what is the difference between short name and logical name. i also got study on that while searching example on sending code.

At the end, thank you very much of guide me. Hopefully can help me on the Short Name also due to me can't really understand the meaning if i study alone.

[RameshRManubolu]

Hi,

    The sequence you have mentioned is correct for any DLMS meter.

    The defference between Logical Name (LN) referencing and Short Name (SN) referencing is, in LN refrencing the request command will contain the OBIS code and attribute ID of the object wanted to read/write, but incase of SN we use class ID and attribute no only, like if the object we are trying to read/write is an data class (class Id - 1) and attribute id no (for example attribute 2 for value of the register).