Load Labware to Deck and Barcode Read Error

I seem to have found an odd bug where if I load a tip rack carrier onto the deck mid method using the DevLibrary and then run the LoadCarrier step the barcode step return data always seems to come back with zeros and no leading 1’s for errors in the step return

This does not happen when I load carriers and plates onto the deck mid-run, so this stark difference makes me believe it has something to do with the tip carrier being loaded in the middle of the method using this DevLibrary run.

@EricSindelar_Hamilton, @ChristianHafele_Hamilton, @WilliamCham_Hamilton am I jsut being a big dumb dumb or is this really a blockage.

@smohler - This is likely due to the labware definition of the tip carrier (.tml file) you are using, and the associated labware properties of that carrier. Some of the default labware definitions have barcode scanning of associated racks turned off.

I recommend the following TML if you aren’t already using it (installs with VENUS):

C:\Program Files (x86)\HAMILTON\LabWare\ML_STAR\TIP_CAR_480BC_A00.tml

If you view the TML carrier definition, you can view its assigned/defined labware properties (you can also view these by selecting the carrier on the deck layout, but you said you were instantiating the labware using the HSL device library).


Many of these properties dictate how the carrier is interacted with during loading/scanning


@NickHealy_Hamilton so should the parameters match exactly what you have on the screen. I load the the BC version of the tml file which solved a problem I earlier with the autoload scanner not even turning over to read.

Now it is turning over to read accept the the step return is just all zeros and the leading string is 0 indicating it doesn’t even sense a no read error

@smohler - I need a bit more detail to better understand what the scenario is. The labware properties for scanning should work fine if you are using the TIP_CAR_480BC_A00.tml definition.

If you are using the dev library to load the carrier to the deck, are you subsequently using the dev library to loading tip racks onto the sites of the carrier before using the ‘Load Carrier’ command (I assume you are using this command as you are parsing the step return from it)?

The default action of the Load Carrier command uses the “?” joker to specify the position string that dictates which carrier sites will be scanned.


“?” will auto dictate that any sites with labware should be scanned, so if the carrier is devoid of labware, the autoload will rotate during scanning, but will not retrieve data from the carrier. This would also prevent any ‘No Barcode’ errors.

If this is not the case, I would need you to please link run traces with the load step returns traced out, as well as a .pkg of the method.


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This was set to “?” but before I use the LoadCarrier step I load tips onto the carrier sites as well. I changed this to “1,2,3,4,5” and when I go in tomorrow I will see if that works.