HTML Parser Settings

There are many legacy instruments or systems which does not support standard industrial protocols like Modbus/Analog outputs. In many cases, there is a HTTP/web server running in the instrument, which can be accessed over Ethernet LAN. Historically, the instruments were connected to PC/laptop directly to PC (or in local LAN). The web pages were manually read by users and the current readings were manually recorded in registers or ERP.

YuDash LYNX supports advanced HTML parsing for IoT enabling of legacy instruments. The feature is explained using a representative instrument with in-built web server.

A) Sample Communication of Instrument with Laptop

A representative instrument within inbuilt HTTP server is connected to laptop through Ethernet cable. The target HTML page (API) will open in the web browser. Please refer to instrument TCP/IP settings and documentation to reach to this point. Typically, the HTTP/web servers are running on IP port 80 and default page of index.html.

B) Integration of YuDash LYNX with the instrument

The laptop is now replaced with YuDash LYNX with similar topology. LYNX work as HTTP client (similar to web browser). Direct peer-to-peer connection is shown below. In practice, it can be connected to instrument (or a server/PC/SCADA) over various topologies, as explained in Modbus TCP/IP section.

The HTML file of instrument will be processed by LYNX to extract applicable tags from HTML tables. The fetched data points will be treated similar to any Modbus/Analog values in rest of flow.

C) Enabling HTML Parser Settings in LYNX

1) Within Feature Settings, Ethernet/LAN and HTML parser is enabled.

2) The Ethernet Settings has to configured as per selected topology. In this example, Static IP settings are being used.

D) HTML Parser Settings

3) The Server settings of the instrument has to be filled within Read HTML Settings block. Click on Read HTML Settings to get present settings. Click on Update HTML Settings after updating settings of Server IP and API (as per below image).

4) The HTML tags have to be configured as per HTML page of the instrument. The Tag Name is the tag within HTML table, the value of which has to captured.

The value is assigned to Variable Name, which will be used in the LYNX data flow.

Besides default HTML parsing in this tutorial, YuDash LYNX supports advanced HTML parsing features. It includes capturing any HTML tags/tables based on the web page. It is done by configuring custom Prefix and Suffix tags for Keys and Values. Please contact us as for more help.

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