W&T connects
Interfaces for TCP/IP, Ethernet, RS-232, RS-485, USB, 20mA, glass and plastic fiber optic cable, http, SNMP, OPC, Modbus TCP, I/O digital, I/O analog, ISA, PCI
Current tools:

OPC Server for Web-IO and serial communication

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Many visualization systems for building and automation technology are able to exchange data using the OPC standard. The OPC server available here permits convenient incorporation of Com-Servers, Web-IOs, Web-Thermometers and Web-Graphs into such systems.

Date Changes and comments Revisions
February 8, 2024
  • Security fix: Unquoted ImagePath in the registry corrected (VDE-2024-018)
  • Support for the new Web Thermometer 8x, #57778
 4.89
EXE download
(approx. 8.7 MB)
August 28, 2023
  • The OPC MiniClient works under Windows 10 again
  • Connections which deliver no files are separated and newly structured
 4.88
on request
August 3, 2023
  • QUALITY BAD handling revised
 4.87
on request
January 12, 2023
  • Optimized polling for Web-IO Digital and Web-IO Analog
  • New: Optional receiving of serial data to a list of Rx items with configurable packet end criterion
  • OPC Mini-Client: Expanded length for item strings
  • Cosmetic changes to manual
 4.86
on request
April 25, 2022
  • New Windows DCOM requirements implemented
 4.82
on request
October 27, 2021
  • New Web-IO 4.0 Digital 4xIn/Out #57733 is recognized and supported
  • New Web-IO 4.0 Digital 12xIn, 8xRelay Out #57738 is recognized and supported
 4.82
on request
October 30, 2020
  • New Web-IO 4.0 Digital 12xIn, 12xOut, 1xRS232 #57731 is recognized and supported
 4.81
on request
January 31, 2020
  • Winsock communication stabilized
  • Error corrected: The idle polling for the Web-IO Climate was done for deactivated devices as well.
 4.80
on request
November 11, 2019
  • JSON upload for reconfiguration revised
 4.79
on request
July 4, 2019
  • Error fixed: In exceptional cases certain packet sizes could cause the OPC server to crash
  • Error fixed: With Web Thermometers the status BAD (last known) could be briefly displayed unnecessarily
  • Error fixed: Web-Thermometer polling optimized
  • Error fixed: Analog Web-IO polling could result in freezing of the second channel
 4.78
on request
December 20, 2018
  • Count value detection when incorporating many Web-IO boxes
 4.76
on request
October 26, 2017
  • Supports Web-IO 4.0 #57734
 4.74
on request
September 7, 2017
  • HTTPS support
  • The Properties dialog for I/O Server now also allows direct entry of a product number.
  • The "Identify" button for I/O Server now tries inventorying on up to four connections at the same time: HTTP on Port 80, HTTPS on Port 443, also (if not already included in the two combinations) corresponding to the current user entries in the dialog and the live opened device data. The main advantage is that "Identify" can now also recognize when a device has been reconfigured from HTTP to HTTPS (or the reverse).
 4.73
on request
November 15, 2016
  • Support for current W&T devices
  • Fixed: The HTTPS option for Web-IO was not stored
  • Fixed: Selective disabling/enabling of the option checks and entry fields when scrolling the combobox was defective
 4.72
on request
September 10, 2015
  • Starting and stopping the OPC service also possible without Admin rights
 4.63
on request
March 23, 2015
  • Connection status available as an item
 4.62
on request
May 21, 2014
  • Support for W&T models #57620 and #57618
 4.60
on request
February 3, 2014
  • Item Quality when using Web-Thermographs remained "good" following connection faults
  • Fixed decimal point counter states from Web-Counter were incorrectly processed
 4.57
on request
26.09.2013
  • Detection time for inactive devices reduced
 4.55
on request
March 21, 2013
  • Handling of counter items for Web-IO Digital after OPC server restart optimized
 4.53
on request
October 11, 2011
  • Combined installation package, German, English
  • *msi download format
  • Optional automatic configuration of OPC mode for Web-IO Digital
 4.51
on request
May 11, 2011
  • Support for W&T models #57630(M), #57631(M), #57634(M)
    (Models with 2MB memory recognizable by firmware starting from V3.xx / Feb 2011)
 4.44
on request
November 3, 2010
  • Support for W&T models #57638 (ERP 2+2 PoE), #57655 (IP Watcher PoE), #57656 (Trap-Receiver)
  • Optimized installation of the OPC server
 4.42
on request
January 6, 2010
  • Items for counter values (Web-Count) optimized

The OPC Server 4.xx is not a direct update for Versions 3.xx. It is installed as a new service with new Server-ID parallel to any existing older Version 3.xx and does not affect the latter’s functionality. Detailed instructions (importing configuration profiles for Version 3.xx, converting OPC clients to new version, etc.) can be found in the online help.

 4.34
on request
September 28, 2009
  • Supports W&T models Web-IO 6xI, 6xO, Digital Logger and Web-Thermograph Relay
  • Optimizing for synchronous item matching in client access

The OPC Server 4.xx is not a direct update for Versions 3.xx. It is installed as a new service with new Server-ID parallel to any existing older Version 3.xx and does not affect the latter’s functionality. Detailed instructions (importing configuration profiles for Version 3.xx, converting OPC clients to new version, etc.) can be found in the online help.

 4.31
on request
May 5, 2009
  • Support for the W&T Web-Count and Web-Alarm models
  • Optimization for rejected connections to Web-IOs and Com-Servers

The OPC Server 4.xx is not a direct update for Versions 3.xx. It is installed as a new service with new Server-ID parallel to any existing older Version 3.xx and does not affect the latter’s functionality. Detailed instructions (importing configuration profiles for Version 3.xx, converting OPC clients to new version, etc.) can be found in the online help.

 4.25
on request
August 19, 2008
  • Polling rate over the network can be limited
    (minimum requirement Web-IO Digital firmware 1.58/2.17)

The OPC Server 4.xx is not a direct update for Versions 3.xx. It is installed as a new service with new Server-ID parallel to any existing older Version 3.xx and does not affect the latter’s functionality. Detailed instructions (importing configuration profiles for Version 3.xx, converting OPC clients to new version, etc.) can be found in the online help.

 4.20
on request
June 12, 2008
  • Improved reopening of the network connection to Web-IO Digital after infrastructure interruptions, e.g. for DSL connection
    (minimum requirement Web-IO Digital firmware 1.58/2.17)

The OPC Server 4.xx is not a direct update for Versions 3.xx. It is installed as a new service with new Server-ID parallel to any existing older Version 3.xx and does not affect the latter’s functionality. Detailed instructions (importing configuration profiles for Version 3.xx, converting OPC clients to new version, etc.) can be found in the online help.

 4.14
on request
March 31, 2008
  • New:
    Additional support of the OPC standard Alarms&Events (for Com-Servers, Web-IO Digital and RFID Servers)
  • Installation includes OPC system files
  • Optimized Reconnect after connection interruptions
  • Expansion of the Mini-OPC client for A&E

The OPC Server 4.xx is not a direct update for Versions 3.xx. It is installed as a new service with new Server-ID parallel to any existing older Version 3.xx and does not affect the latter’s functionality. Detailed instructions (importing configuration profiles for Version 3.xx, converting OPC clients to new version, etc.) can be found in the online help.

 4.10
on request
January 11, 2008
  • New architecture: The OPC server works as a background service with separate configuration program
  • Support for OPC DA 3.0 (OPC Alarms&Events in development)
  • New mapping concept for Web-IO Analog and Climate data
  • Updated and expanded online help
  • Various internal optimizations/changes

If when or after starting the OPC client a message appears that no OPC servers are available, the system may be missing the required OPC core components. You can download these in Version 3.00.102 here and install them. Alternatively you can always find the most current version in the download area of the OPC Foundation at https://opcfoundation.org (OPC Core Components x.xx Redistributable).

 4.00
on request
March 29, 2007
  • Supports new W&T devices: Web-IO, 12x Digital Input, 6x Digital Relay and Web-IO Thermohygrobarometer
  • With the Web-IO Digital the command for setting outputs is not issued over the network until the output actually changes its state
 3.34
on request
April 25, 2006
  • Installer change: Registers the program again in "App Paths"
  • OPC server for very fast computers optimized
  • Collision recognition over multiple sessions (e.g. under XP with
    fast user changing)
  • NEW: OPC item names are now freely definable
 3.31
on request
October 17, 2005
  • Clearer indication of started OPC servers
  • Supports Web-IO Analog-In (V+A)
  • Various corrections in the response for opening a connection to the Web-IO Digital
  • Error eliminated: An OLE problem was erroneously reported when WinSock was not installed.
 3.19
on request
May 12, 2005
  • Optimized reopening of the TCP connection after faults in the network infrastructure
 3.17
on request
April 12, 2005
  • Supports EnOcean module type STM 250 (window magnet sensor)
  • Errors corrected: EnOcean transceivers were mistakenly set for hardware handshake.
  • Optimized: Connection to Web-IO Digital was opened delayed by one clock
    of the polling rate
  • Optimized: Connection to Web-IO Digital was sometimes unnecessarily
    disconnected and reopened
 3.15
on request
February 9, 2005
  • New file-based configuration concept in place of
    registry entries
  • NEW: Support for Web-Thermo-Hygrograph
  • NEW: Support for EnOcean-Com-Servers
 3.11
on request
July 19, 2004
  • Optimizing when writing variables when connections are faulty
  • Detailed error logging
  • Optimized window layout
 2.19
on request
June 16, 2004
  • Installation will now take place as an MSI package
  • Optimization of the self-registration
 2.17
on request
April 23, 2004
  • Functions for Web Thermometers added
 2.15
on request
August 20, 2003
  • Extended OPC server functions for Web-IO Digital
    (password protection and read-out of the counters)
 2.10
on request
July 29, 2002
  • When called by the client application, the OPC server starts invisibly in the background (protection against the user manipulating the application)
 2.08
on request
April 9, 2002
  • Error in the namespace browser rectified
  • VBA example revised
 2.07
on request
August 20, 2001 OPC server for Windows NT/2000/95/98/Me 2.05
on request