LK220 Thermoelectric Liquid Chiller

April 27, 2023 • 4 min read

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LK220 Thermoelectric Liquid Chiller

This Thermoelectric liquid chiller from Thorlabs can be controlled via serial communication using usb interface.

Prerequisite

Please install the PySerial package by running the following command:

pip install pyserial

Also you will need the appropriate .dll files to control this chiller which can be downloaded from Thorlabs. Since this program currently uses .dll files, this example only works in Windows Os.

Example

from tllk220 import TLLK220

def main():
    dll_path = "path/to/your/dll"  # Replace with the appropriate path to your DLL
    lk220 = TLLK220(dll_path)

    # List connected LK220 devices
    devices = lk220.list()
    print("Connected devices:", devices)

    if not devices:
        print("No devices found. Please check the connections.")
        return

    serial_no = devices[0][0]  # Use the first device's serial number
    n_baud = 115200  # Baud rate
    timeout = 1000   # Timeout in milliseconds

    # Open the device with the given serial number, baud rate, and timeout
    handle = lk220.open(serial_no, n_baud, timeout)
    print(f"Opened device with handle: {handle}")

    # Enable the chiller
    lk220.set_enable(handle, 1)
    print("Chiller enabled")

    # Set target temperature to 20°C
    target_temp = 20
    lk220.set_target_temp(handle, target_temp)
    print(f"Set target temperature to {target_temp}°C")

    # Wait for 10 seconds
    import time
    time.sleep(10)

    # Disable the chiller
    lk220.set_enable(handle, 0)
    print("Chiller disabled")

    # Close the device
    lk220.close(handle)
    print("Device closed")

if __name__ == "__main__":
    main()

This example code does the following:

Imports the necessary modules and the TLLK220 class from the tllk220.py file provided.
Defines a main function that:
- Assumes you have your TLLK220 connected to a serial port and the DLL is available on your system.
- Lists the connected LK220 devices.
- Opens the device with the given serial number, baud rate, and timeout.
- Enables the chiller.
- Sets the target temperature.
- Waits for 10 seconds.
- Disables the chiller.
- Closes the device.

Make sure to replace the dll_path variable with the appropriate path to your DLL. The required Thorlabs.LK220.CommandLibrary-win32.dll is typically found in C:\Program Files (x86)\Thorlabs\LK220\Sample\Thorlabs_LK220_PythonSDK.