Instrumentation sheets

nom mis reads an instrumentation sheet, also called a signal or channel list, and sets the description and unit of each matching channel in a dataset.

You need a profile from API keys setup. Excel files need the mis extra, and .xls files also need pip install xlrd. To set units from Python instead, see Channels and data types.

Prepare the sheet

The sheet is a CSV or Excel file with a Channel column, and optional Description and UCUM Unit columns. Column names are case-insensitive, and other columns are ignored.

Channel,Description,UCUM Unit
RPM_ENGINE_1,Engine 1 rotational speed,/min
TEMP_EGT_1,Engine 1 exhaust gas temperature,Cel
PRESS_FUEL_1,Engine 1 fuel pressure,bar
SPEED_IAS,Indicated airspeed,m/s

Units are UCUM symbols, such as Cel for degrees Celsius. To convert your own unit names, list the units Nominal knows and map yours to them, for example with XLOOKUP in Excel:

nom mis list-units --profile default --output units.csv --format csv

The file has a UCUM column with the symbol and a Unit Name column.

Check the units

nom mis validate --profile default mis.csv

It lists units that Nominal doesn’t recognize. Those still display in Nominal, but workbooks can’t convert them.

Apply the sheet

nom mis process --profile default mis.csv --dataset-rid <DATASET_RID>

Channels match by exact, case-sensitive name. The command warns about sheet rows with no matching channel. By default, it skips a channel whose existing description or unit differs from the sheet, with a warning. Pass --override-channel-info to replace them.

For an Excel file with several sheets, pick one with --sheet "Instrumentation". validate takes the same option.