A Digital Chart-Recorder Interface for Use with Old Waters HPLCs

We have an old Waters HPLC setup sitting around: a 515 pump connected to a 2487 dual wavelength detector. It still works great, but it's hooked up to an old chart-recorder. As in, a device with a rolling drum of paper and electronically controlled pens. I had a lot of fun using the chart recorder at first, but once the novelty wears off, it's quite cumbersome: so I put together an interface to generate chromatograms on a computer instead.

This program is specifically designed to read from the ADC-10-F103C, an inexpensive 10-channel ADC board with a USB adapter. You can get these for $5-$20 from eBay, Amazon, AliExpress, etc.

Instructions:

Setting up the detector

• Make the connections in the above diagram. For more information, see page 71 of the 2487 detector manual: 'Connecting the 2487 Detector to a Chart Recorder'
  • Note: you don't have to connect the red wires to specifically IN8 and IN1, but if you do anything different, make sure to edit the ACTIVE_CHANNELS variable at the top of the script.
• Plug the device into a USB port and run the program

Usage

• Make sure you have Python 3.10, matplotlib, and tkinter
• On Linux, the serial port is typically /dev/ttyUSB0
  • If you're on Windows, google something about COM ports. I don't have Windows so I can't test it!
• If you get a Permission denied error when trying to initialize a connection, try;

$ sudo chmod o+rw /dev/ttyUSB0

• Controls are self explanatory
• By default, the plot scrolls to fit the chromatogram. Hit Unlock View to disable this, if you wanted to zoom/pan around. Hit Lock View to return to automatic scrolling