L-INX User Manual
203
LOYTEC
Version 4.0
LOYTEC electronics GmbH
9.1.3.4 Trend Log Objects
Each trend log object on the device is represented by a folder in the OPC name space. This
folder contains a number of tags describing and controlling the trend log. To retrieve log
records, however, the XML-DA tag interface cannot be used. There are two options:
retrieve the complete log as a CSV file, or use the LOYTEC proprietary Data Log Web
service (XML-DL). That Web service uses the logHandle provided by a tag. The CSV file
location can be obtained from a tag also.
ServiceType (string, Read-only, const): This is a constant tag of type string, which
contains ―trendLog‖, or ―alarmLog‖. It identifies this folder as a trend log, data log or
alarm log folder. This can be used as an additional identification to the vendor-specific
property of the node tag.
Purge (Boolean, read/write): When writing TRUE to this tag, the log is purged.
TotalCnt (unsignedInt, read-only): This tag contains the total number of logged
records. This number can be larger than the BufferSize.
BufferSize (unsignedInt, read/write): The size in records of the log buffer. Writing to
this tag can resize the log buffer, if it is disabled.
LogHandle (string, read-only, const): This handle specifies the data log. The logHandle
must be used with the proprietary Data Log Web service.
CsvFile (string, read-only, const): This tag specifies the file path and file name of the
CSV data log file.
CentralDL0, CentralDL1 (string, read/write): These tags serve as placeholders for the
central data logger to store its URI. The tag CentralDL0 is intended for the primary,
CentralDL1 for the secondary central data logger. The tags are stores in non-volatile
memory and retain their values over a power-on reset. For more information on the
central data logger refer to the LWEB-801 User Manual [5].
9.1.3.5 E-mail Templates
E-mail templates can be configured in the Configurator software. When an e-mail template
is triggered, the corresponding e-mail is transmitted. The e-mail template can also be
triggered over the OPC interface. Therefore, a node is added to the OPC name space for
each e-mail template under the ―E_Mail‖ node.
Each e-mail node is named after the e-mail template and contains the following OPC tags:
ServiceType (string, Read-only, const): This is a constant tag of type string, which
contains ―email‖. It identifies this folder as an e-mail template folder.
Send (Boolean, read/write): When writing TRUE to this tag, the e-mail transmission is
triggered.
9.2 Using L-WEB
The L-WEB is a Web-based visualization software that comes free with the device. It uses
the standard Web technologies to visualize and control data provided by one or more
L-INX Automation Servers on a Windows PC.
The L-WEB software uses the standardized OPC XML-DA Web service to communicate
between L-WEB and remote L-INX Automation Servers, which makes it extremely
firewall-friendly and easy to setup.
