Historical data from Ignition is not immediately compatiable with Bar Chart data because a bar chart shows quantities for a given category, and historical data is stored point-by-point with a timestamp and value. If you’re trying to group the historical data together in some way, you’ll need to do some data processing before passing a dataset to the “data” property of the Bar Chart. You mentioned in your other thread voltage and current, how are you trying to represent this data in a bar chart? Average voltage/current in a month? This is important in figuring out how exactly the data needs to be arranged in order to work with a bar chart.