Applies To:
  • CitectSCADA 3.21, 3.30, 3.40

I have found that when the trends get printed;
  1. The colours in which the trends are printed in are different from the colours displayed on the trend page.
  2. Citect experienced intermittent communication problems with our I/O devices.
  3. The printer driver software reports that it has lost communication with the printer.

  1. Trend Colours and Printing:
    • The fix is to use the new Cicode library files GRAPH.CI & ZOOM.CI. 
    • The new files are now included in Service Pack F for Citect Version 3.40.
    • Copy the files into the include project and recompile your project. The new functions should work for Citect V3.21, V3.30 projects also.
  2. Communication with I/O devices during printing:
    • If the Trend Server is also an I/O Server and there is high CPU usage (up to 100%) during the trend printing then try the suggestions in the article General Printing Problems, Q1795. High CPU usage may be responsible for communication problems with I/O devices. Trend printing is an intensive task so try and get the CPU usage back to an acceptable level during printing. For example certain Windows printer properties such 'Fast Printing Direct to Port' may be the cause of this, you should ensure this option is unchecked.

  3. Printer Driver:
    • There are a number of causes here, first check the above Knowledge Base article. You can try another printer driver, you should Download the latest driver software from the printer vendor (and/or try one of the Windows drivers, for example choose a low end model of the printer if available and see if this helps).
    • Secondly printing problems may occur due to the use of cheap non compliant printer cables. Ensure that the cable is marked with:"IEEE Std 1284-1994 Compliant" or manufactured to be compliant with this standard. Also referred to as double shielded cables.
    • In areas susceptible to electromagnetic or radio frequency interference (EMI/RFI eg. in plant rooms, near switching equipment, etc) it is possible to get printing problems using a cable that is not shielded correctly. This is especially true with cables longer than 2 metres used on PC's with extended capability ports attached to the latest model printers based on the Windows Printing System. Many cables are not manufactured to any such standard.