RetroPrinter.com

How the Retro-Printer is Assisting Industry

Thanks to our long-term connection with leading industrial controls company (Michael Jackson Controls Limited), we have been able to understand the requirements for connecting to PLCs and other industrial controls; resulting in bespoke software for the Retro-Printer module.

This includes the following e-print solutions:

Autoclaves

Many autoclaves in use within the medical industry have the ability to print their output to a connected HP printer via a parallel port.  Rather than updating to a network or USB enabled autoclave, the Retro-Printer allows these machines to remain in use.  No longer do technicians need to print off the reports and scan them, in order to add to their existing IT systems – the Retro-Printer simply connects and converts the output to PDF for access via a network.

We did however, need to add the ability to ignore specific control codes as we found that some autoclaves were changing print quality in the middle of the page. According to the HP documentation, this should only be done at the start of a page and will otherwise cause a form feed.  Obviously it doesn’t on some HP (or compatible) printers.

Allen-Bradley / Rockwell PLC5

Here, the customer needed to monitor the output of a foundry sand system.  Every time that it mixes a batch of sand, the PLC prints a one line report of the sand properties for that batch (moisture, temperature, weight, green strength, water needed, etc).

This was formerly being sent to an old Epson printer that used continuous feed paper which would be torn off at the end of each day.  For reporting, the data had to be scanned in and attached to a report. The other options would have been changing the system to connect a Modbus/TCP gateway to the PLC-5, which would have needed new PLC programming and commissioning.  Although we could help the customer with the PLC programming required, it was more cost effective to find a simpler way of capturing the output from the process.

Here, we created bespoke configuration options for the Retro-Printer which allows for continuous printing and generation of a multi-page PDF once the PLC issues a Form Feed (FF) character which signifies the end of  job.  The customer then wrote a simple python script to allow them to pass the captured data into a time series database which was already being monitored throughout the facility.

Siemens S5

This was a similar project to the PLC5 project above, except it needed some understanding of how Siemens PLCs work and particularly, the CP523 serial interface.  The customer runs an industrial cleaning process where each job can take anywhere from 20 minutes to 5 hours.

Originally, the data was printed on reams of continuous paper using a Siemens PT88 line printer.  This printer was worn out and the customer was concerned about finding a replacement.  Siemens were unable to assist, and no longer had any information on the control codes supported by the PT88 even.

We worked with the customer to connect the Retro-Printer using a custom serial to centronics interface, in order to initially caputre the output from the cleaning process so that we could determine what printer control codes were in use.  We then replicated the output in our offices, and identified that the Cp-523 was sending only 7 bit data, with minimal control codes.

We then used our PLC expertise to  examine the PLC code to determine all of the potential messages which could be output by the system to the serial card.  Having does this, we worked closely with the customer to determine specific phrases which indicate the start and end of a print job, and amended the Retro-Printer software to look for those specific phrases in the captured data, using them to trigger a new PDF output file.