Opening mode of connection with the device and a used link protocol.

If the device is configured so that it directly uses DLMS/COSEM protocol on the given interface, set this parameter to "Direct HDLC".

Mostly (e.g. when reading through IR optical interface by an optical reading head) you must open the connection in IEC protocol in so-called "mode E" and then transfer to HDLC binary protocol (i.e. DLMS/COSEM).

"IEC mode E", according to the specification of the IEC protocol, uses the following settings of the transmission parameters:

• baud rate 300 Baud,

• 7 data bits,

• even parity,

• 1 stop bit.

If "Opening Mode" is set to "IEC mode E", the above-mentioned transmission parameters must be set. As for the Serial communication line, the parameters must be set in the line parameters "Mode 1". See the protocol parameter "Software 7E1".

The setting of the baud rate to 300 Baud is usually not required when using the line of the MODEM category. A so-called DTE speed is used between a PC and a modem. If this speed is higher than 300 Baud, you have to activate the "handshaking" parameter on RTS/CTS in proper line mode.

If the parameter value is set to "Direct HDLC", a dynamic change of transmission parameters is not expected. You can use any Serial line mode and set it by the "Line mode" parameter on the station.

More information is mentioned in IEC 62056-21, Electricity metering - Data exchange for meter reading, tariff and load control - Part 21: Direct local data exchange, Annex E: "METERING HDLC protocol using protocol mode E for direct local data exchange".

See also the chapter "Setting of transmission parameters".

The "UDP Pure" mode is used by some devices when communicating over UDP. Each DLMS/COSEM data packet (challenge/response) is in a separate UDP packet. In the case of TCP, this is problematic (without parsing it is not possible to determine what the size of the DLMS/COSEM data packet is) so the DLMS/COSEM standard defines the use of an envelope - called a Wrapper - for TCP/UDP mode (see next paragraph).

The "TCP/UDP Wrapper" mode is used when communicating over TCP or UDP. An 8-byte header (Version, Wrapper Source Port, Wrapper Destination Port, and Length fields) is added to the DLMS/COSEM data.

The "TCP/UDP Wrapper + Gateway protocol" and "Gateway protocol" modes are used when communicating over TCP or UDP through a so-called Gateway device. A prefix is added to the DLMS/COSEM data (single-byte fields Header, Device Network ID, Address Length, and variable-length field Device Address). Based on the Device Network ID and Device Address, the Gateway can distinguish which target device to route the request to. The device response is routed to the D2000 kOM process, and the prefix this time contains its identification (My Network ID, My Address).
In addition, in the "TCP/UDP Wrapper + Gateway protocol" mode, the same header as in the "TCP/UDP Wrapper" mode is added. When using UDP, some devices may omit the header, similar to the "UDP Pure" mode.

The "Consereth" mode is used when communicating via TCP/IP by Iskraemeco devices (e.g. Iskra MT880). A 3-byte header is added.

Direct HDLC
IEC mode E
UDP Pure
TCP/UDP Wrapper
TCP/UDP Wrapper + Gateway protocol
Gateway protocol
Consereth

Direct HDLC

--- DLMS/HDLC parameters ---

The setting of the "Application Context" parameter of the DLMS/COSEM protocol.
Short_Name_Referencing_No_Ciphering context is supported for "Short Name (SN) referencing". Logical_Name_Referencing_No_Ciphering context is supported for "Logical Name (LN) referencing".
The next two contexts with encryption are not supported.

Logical_Name_Referencing_No_Ciphering
Short_Name_Referencing_No_Ciphering
Logical_Name_Referencing_With_Ciphering
Short_Name_Referencing_With_Ciphering

Short_Name_Referencing_No_Ciphering
 

HDLC MAC address of a client (i.e. D2000 KOM process). The default value is 10H which is the reserved value "Public client".

Open

See "DLMS UA 1000-2 Ed. 7.0" document, chapter 8.4.2.3 "Reserved special HDLC addresses".

For the ADDAX NP73E.2-18-1 electricity meter, a different value than 10H had to be configured (1 or 2).

For the ISKRA MT880 electricity meter, it was possible to read only a limited set of data (e.g. serial number) with a value of 10H. Active and reactive power could be read as 01H (Client Management Process) or 02H.

0 .. 7FH

10H

The maximum length of one HDLC frame packet on the receiver's side. When communication problems occur (e.g. checksum error etc.), we recommend decreasing the value of this parameter.

250

The maximum length of one HDLC frame packet on the transmitter's side. When communication problems occur (e.g. checksum error etc.), we recommend decreasing the value of this parameter.

250

The maximum length of PDU (data packet). One PDU can be divided into more HDLC frame packets according to settings of protocol parameters HDLC Max_info_field_length-receive and HDLC Max_info_field_length-transmit.
Note: A specific electricity meter (Landis + Gyr ZMD 400) only accepted a value of 0, otherwise it returned a rejected-permanent error during connection establishment. Other electricity meters (Landis+Gyr ZFD 405 and Landis+Gyr ZMD 410 CT44) only accepted the value 65535, otherwise they returned a rejected-permanent error during connection establishment.

0 .. 65535

1200

A Disconnect request will not be used after the readout of values from a device is finished. During the next readout, a connection establishment phase is omitted (HDLC mode-setting request and AARQ negotiation request).
This allows for greater data throughput and an increase in the frequency of reading values from the device.

YES/NO

NO

Waiting before reading from the station. Waiting makes sense if there are multiple meters on the line to detect the end of the previous communication and start listening for the request.

ss.mss

00.000

Waiting before sending an HDLC message.

ss.mss

00.000

Number of HDLC messages sent in case of error (received incorrect/no response). The parameter is active only for Mode:

• Direct HDLC

• IEC mode E

• Consereth

1-100

1

Device password. If entered, the "Low Level Security" authentication with the entered password is used within the AARQ Association Request.

Online address selection from the list of objects, directly on the device, through the DLMS Object List dialog box in the configuration of the I/O tag address will be disabled.
Disabling browsing makes sense in a production environment if values are to be read on a several-second basis and reading a list of objects, which can take up to several minutes, is not acceptable.
Some devices (e.g. ADDAX NP73E.2-18-1) do not support the reading of the object list.

YES/NO

NO

Several electrometers implement optimization of time data when reading from profiles (class_id=7). The optimization means that only the first row of data contains a timestamp, others contain null. The timestamp of each row is equal to the previous row's timestamp plus the value of the capture_period (4) attribute.

If the value of this parameter is YES, the value of the capture_period attribute is read prior to reading the profile data. If the value of this parameter is NO, the content of the capture_period attribute is not read, but the KOM process relies on all profile rows to contain timestamps. If this is not the case, the profile data is not read, and the line logs contain the error messages "turn on station parameter 'Profile Data Optimization".

YES/NO

YES

Bit settings in the "xDLMS Conformance" field in the AARQ initial message. The default settings are:

• for Application Context "Short Name (SN) referencing" read/write/parameterized-access bits 

• for Application Context "Logical Name (LN) referencing" get/set bits

Open

0

0

If the value of this parameter is YES, octet-string values will be interpreted as text strings (e.g. "abc") for text I/O tags, otherwise, in binary format, individual octets are separated by a dot (e.g. "97.98.99").

YES/NO

NO

--- IEC Parameters ---

It is an address of a station (device) and is used only if the Opening mode is set to "IEC Mode E".
This parameter is optional. It identifies the address of the device at the beginning of communication via the IEC protocol. If this parameter is not defined, the address will not be set at the communication via the IEC protocol and the device must always respond.
If several devices are connected to one line (e.g. RS485 bus), the IEC address of a device must be set so that the devices can be identified and avoid a collision. A device address is max. 32 characters consisting of figures (0...9), capital letters (A...Z), small letters (a...z), or a blank space ( ). Zeros in front of the valid number are ignored (i.e. address 10203 = 010203 = 000010203).

"IEC Device Address" is the serial number of the device. In OBIS addressing, this register has an address "0-0:C.1.0" - Device ID 1, manufacturing number.

The picture below shows the front panel of the EMH LZQJ device. There is a serial number, i.e. IEC address (563911). If the device contains a display, this value may be usually displayed as you can see in the picture.

Open

-

This parameter is used only if the Opening mode is set to "IEC Mode E".

It defines the baud rate for the communication through HDLC protocol DLMS/COSEM after the changeover from IEC mode E to the HDLC binary communication.

As for the Serial line, this parameter must set the baud rate to "Mode 2" of the line.

AUTO option sets the baud rate according to the value offered by a device. If this baud rate can not be identified, you should check the diagnostic communication logs, where  the following message can be found:

and set the baud rate according to it.

HDLC binary communication through DLMS/COSEM protocol, unlike the opening IEC step, is realized by different parameters that have to be set in "Mode 2" of the Serial line category:

• 8 data bits,

• none parity,

• 1 stop bit.

See also the "Software 7E1" parameter and the chapter Settings of transmission parameters.

300
600
1200
2400
4800
9600
19200
AUTO

AUTO

This parameter is used if "Opening mode" is set to "IEC Mode E".

Setting it to YES activates an SW emulation of transmission parameters of 7 data bits and even parity when the transmission parameters of 8 data bits and none parity are set (i.e. emulation of 7E1 when 8N1 is set). It enables the use of the "IEC mode E" option for SerialOverUDP lines that do not support dynamic changes of transmission parameters.

See the chapter Settings of transmission parameters.

YES/NO

NO

This parameter is used if "Opening mode" is set to "IEC Mode E".

Nonzero value activates the sending of a so-called "wake-up message" which activates the communication interface of battery-powered devices. The null characters (0x00) are sent according to the quantity that is defined by the parameter value. The baud rate must be 300 Baud (configured in "Mode 1" for Serial lines).

More information is available in IEC 62056-21, Electricity metering - Data exchange for meter reading, tariff and load control - Part 21: Direct local data exchange, Annex B: "Wake-up methods for battery-operated tariff devices".

0 .. 120

0

This parameter is used if "Opening mode" is set to "IEC Mode E".

If a so-called "wake-up" message is activated, this parameter defines a delay after sending a "wake-up" message, before the beginning of communication. In the case of a Serial line, we recommend setting the "WaitTxEMPTY" parameter in a specific line mode.

According to document IEC 62056-21, you should set this parameter between 1,5 and 1,7 seconds.

ss.ms

0

--- TCP/UDP Wrapper parameters ---

This parameter is used if the "Opening mode" protocol parameter is set to "TCP/UDP Wrapper" or "TCP/UDP Wrapper + Gateway protocol". It specifies the value of the Source Port field (2-byte number) in the wrapper header.

Reserved ports are according to the standard:

• No-station: 0x0000

• Client Management Process: 0x0001

• Public client: 0x0010

• Open for client SAP assignment: 0x02 .. 0x0F,  0x11 .. 0xFF

-

0

This parameter is used if the "Opening mode" protocol parameter is set to "TCP/UDP Wrapper" or "TCP/UDP Wrapper + Gateway protocol". It specifies the value of the Destination Port field (2-byte number) in the wrapper header.

Reserved ports are according to the standard:

• No-station: 0x0000

• Management Logical Device: 0x0001

• Reserved: 0x0002 .. 0x000F

• Open for client SAP assignment: 0x0010 .. 0x007E

• All-station (Broadcast): 0x007F

-

0

--- Gateway parameters ---

This parameter is used if the "Opening mode" protocol parameter is set to "Gateway protocol" or "TCP/UDP Wrapper + Gateway protocol". It specifies the value of the Device Network ID field in the prefix in the sent request.
If only one network exists, value 0 shall be used.

-

0

This parameter is used if the "Opening mode" protocol parameter is set to "Gateway protocol" or "TCP/UDP Wrapper + Gateway protocol". It specifies the value of the Device Address field in the prefix in the sent request.
Note: in the case of the Iskraemeco AC750 gateway, the 8-byte MAC address of the meters on the Power Line Communication bus is used as the Device Address.

-

-

--- Send/receive parameters ---

The delay after sending the request but before reading the response.

ms

100 ms

The delay between readings of the response until its completion.

ms

200 ms

A retry count of reading response until its completion.

1 .. 100

20

The delay between the request retries if a communication error occurs.

ms

500 ms

A retry count of a request if a communication error occurs.

1 .. 20

3

--- Modem parameters ---

The phone number for modem connection with a device (only for MODEM lines).

Maximum waiting time for dial-up modem connection (only for MODEM lines).

1 .. 600 s

60 s

A maximum retry count of dial-up modem connection (only for MODEM lines).

1 .. 20

1

Delay before attempting to dial after an unsuccessful connection attempt (only for MODEM lines).

1 .. 600 s

30 s

Time delay after the dial-up connection has been established (only for MODEM lines) but before the beginning of communication.
It is used to stabilize the modem connection for old types of modems. After this timeout elapses, all the redundant received data (the residues of AT modem communication) will be read and ignored.

0 .. 30 s

5 s

AT Command 1