Using a Lookup Table
Any of the Screen Objects that can poll for data such as a Data Window, Level Gauge, Dial Gauge, or Meter Gauge can use a Lookup Table to convert the data by matching it with known substitution values. This is very helpful when reading data from a non-linear sensor which can't be converted using the normal built-in multiplication and offset factors of the Screen Objects.
To create a Lookup Table, a standard text file is used which contains two columns of data separated by a delimiter. The delimiter can be a Comma, Space, or Tab character. The column on the left side should contain the set of data values that the Screen Object will search and match with the data that it received via a polling command. The column on the right should contain the data that will replace it. If a direct match is not found, linear interpolation will be used based on the nearest matching values in the table. If the data is outside the range of the Lookup Table's upper or lower limits, the word "Error" will be sent to the Screen Object. This file can be used as a Lookup Table for multiple Screen Objects if needed.
The decimal point position of the data shown in the Screen Object's window will be that which is used in the substitution values of the Lookup Table. Make sure that each data value in the right-hand column contains the same number of digits to the right of the decimal point for consistency. Data in the left-hand column does not matter because it is only being used to find a match.
Note, if the Lookup Table file contains unexpected characters, or an invalid format, an error box will pop up when a Screen Object tries to use it. If this should occur, open the Lookup Table file and look for extra delimiters, extra carriage returns, or non-numerical text characters other than a negative sign or decimal point.