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OMV24

OMV24

okt 13, 2017

OMV24 communication protocol

Supported device types and versions
Communication line configuration
Communication station configuration
I/O tag configuration
Redundant system
Errors and problems
Literature
Changes and modifications
Document revisions

Supported device types and versions

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Communication line configuration

Communication station configuration

  • Communication protocol "OMV 24".

  • Address parameter is not required. The communication line can be used only for one Gaspartner.

The text messages are not supported.


Station protocol parameters

Communication station - configuration dialog box - tab "Protocol parameters".
These parameters influence some optional parameters of protocol. You can set the following station parameters:

Table 1

Key word

Full name

Meaning

Unit / size

Default value

WT

Wait Timeout

Delay between the response reading until it is completed.

ms

1000 millisec.

SCAN

Scan-only Mode

Permanent passive mode of data scan only (mode 2).

YES/NO

NO

PERIODE

Write Periode

Transmission period of output data block. A station must be in an active mode 1. If the valid data have not been received and three-time of this time elapses, the station switches to a communication error after.

sec

60

TM_FACTOR

Write Collision Delay

Timeout of two functions:

  1. If there are some communication problems (full input block has not been received, noise ,etc.), the receipt is totally reinitiates and uncompleted data are ignored after the time elapses since receiving the last data.

  2. Output data block is sent after this time elapses since the receiving the last valid data.

sec

10

TRACE_VAL

Trace Values

Detailed tracing of data (e.g. through D2000 SysConsole). Detailed data about an analyzed value are written after every recorded line.

YES/NO

NO

TMASK

Time Value Mask

Mask for date and time conversion from received data.

-

yy-mm-dd hh:mi

MOXAT

Moxa Timeout

Timeout for detection of failure of one communication line on SerialOverUDP Device Redundant lines. After elapsing the timeout since receiving the last character, the communication is redirected to other communication line, i.e. reading/writing will be done via secondary / backup device.

mi:ss

02:00

SENDT

Send Delay

Delay between sending individual lines of a communication message.

sec

0.000

String containing the protocol parameters is defined as follows:

Key_word=value;Key_word=value; ...

Example:

WT=400;PERIODE=20;

If there is used a keyword with an invalid value in the initialization string, there will be used corresponding default value according Table 1.

I/O tag configuration

I/O tags: Ai, Ci, Di, Qi, Ao, Co, Do

The Gaspartners transfer each other data in blocks with defined periodicity. A received input block is analyzed and the value are assigned to the proper input tag according to the parameter Identifier (Ai, Ci, Di or Qi). Output block consists of output tags (Ao, Co and Do). These output tags must contains a control object, tab "Control of output".
Note: I/O tag of Qi type, which is used as the control object, used for output tag Co.

Identifier

The blocks of data are transferred during this communication. Every object (I/O tag) has its unique number "Identifier", which is required. Identifier is a number in the range of 1 up to 998 (0 and 999 are reserved). The same values of Identifier can be used in both input and output block.

Exponent

Exponent is a value that should be defined for Ai, Ci, Ao and Co tags. The input value from the communication is recalculated by a result 10^Exponent. The implicit value is 0 (i.e. input value *1). For Ao and Co tags, the calculation is the same and the result is sent by output data block. 

Decimal places

Number of decimal places for Ao (output tag). It defines an accuracy of sending data to Gaspartner.

Redundant system

This protocol supports two modes of activity: