LS-THC Firmware Update for Bug Fixes (Current Version is V1.09 on 5/1/20)

The following guide provides instructions for how to flash the current version of the LS-THC firmware onto your unit using your computer through the USB cable. If you are experiencing any of the issues that are detailed in the revision log below, we encourage you to flash your LS-THC with the latest version of firmware available. You will need a Windows computer to flash your LS-THC unit. If you do not have internet access at your machine, you can bring your computer to a place where you have internet to download the folder in Step 4 below and complete the installation without internet.


  • V1.02 Initial Release (1/30/20)

  • V1.03 Internal Release (2/2/20)

  • V1.04 (3/17/20) This version fixes the issue that some users are experiencing with unnecessary ‘Arc Voltage Lost’ warnings in FIreControl that occur during piercing and also at the end of cuts. With this patch, you should now be able to use lead-outs with your programs. As for the pierce delay value at the start of cut loops, we have noticed many users are using a pierce delay that is too short. This will cause the torch to fire the pilot arc and start moving before the arc can successfully pierce the material which can cause cut quality issues. We suggest using the pierce delay override feature in FireControl to dial in this delay value on the fly while cutting.

  • V1.05 (3/20/20) Fixes bug in the ‘crashed torch’ up correction move when using Nominal Voltage setting. Also fixes the UP & DOWN display LEDs in FireControl.

  • V1.06 (3/30/20) Fixes a firmware bug where the torch rises after a few cut loops.

  • V1.07 (3/31/20) Lowers the threshold for Arc Voltage lost to 10 Volts

  • V1.08 (4/9/20) Fixes a firmware bug where stack-up motion steps are not cleared on THC deactivation.

  • V1.09 (5/1/20) Fixes IHS trigger issue preventing recovery.


The below guide provides instructions for updating the firmware on your LS-THC device.

  1. Close FireControl software and any other open applications. Make sure that your CNC electronics box is plugged into your computer with the supplied USB cable and that your THC unit is installed into the USB Motion Control Board inside the CNC electronics enclosure.
  2. Move your mouse down to the taskbar and type in ‘Device’ into the search bar. The Device manager should pop-up in the search field and click this link as shown below.

  1. In the Device Manager menu, navigate to Ports (COM & LPT) and click the arrow to expand this sub-menu. You should see at least two USB devices connected in this menu, one device connection is for the USB Motion Control Board and the other is for the LS-THC unit. The LS-THC unit will have the term ‘CH340’ in the device title. Once you find this device, note the COM# that is associated with this device. In the example below, the COM port for the LS-THC is COM16.

  1. Next, navigate to an internet browser and open the following link:

This will download a .zip file containing the latest LS-THC firmware file and the Windows program that we will use to flash the firmware onto your LS-THC unit.

  1. Next, open the folder where the zip file was downloaded and right click the file and select ‘Extract All’ as shown below. Next, click Extract. (Note: you may need to use another 3rd party program in order to unzip this file in Windows 7 & 8).

  1. After the folder has been unzipped, click the folder ‘LS-THC FIRMWARE UPDATE’. You should see a total of 7 files in this folder.

  2. Once in the folder, click the file Xloader.exe as shown below.

  1. A small application window for the Xloader program will automatically open up. If you do not see it appear, minimize any open windows as it may be below these windows. The program should look like what is shown below.

  1. Next, to the right of the top entry field for Hex File click the box with the three dots. Once here, navigate to the unzipped folder ‘LS-THC FIRMWARE UPDATE’ and select the ‘LS-THC_v1.09.hex’ file inside this folder. Note: the latest firmware version at the time of writing this guide is v1.09.
  2. Next, in the device drop-down menu select LS-THC.
  3. Refer back to the COM port # that you noted in step #3 and select this device from the COM port drop-down menu.
  4. Make sure your Baud rate is set to 115200 as shown.
  5. Finally, click the Upload button. The bottom status bar should say ‘Uploading’ and this process can take up to 45 seconds. After completion, you will see the status bar updated letting you know that the file was successfully uploaded.

  1. Open FireControl and connect to your LS-THC as normal.