You could go about this one of two ways. You could choose to attach horsepower as a metadata property to one or all of the tags associated with a pump, or you could choose to create individual pump classifications based on horsepower.
For the first solution, you would adjust your logging session to include pump horsepower as a metadata property. Note, OPC DA would not work with this format as the metadata fields are not dynamic.
For the second solution, you can classify your asset type as '5hp Pump' or '3hp Pump'. Because tags can live in multiple asset types, you could still have a third generic 'Pump' asset type as well. This path is very easy if the tag names already have logic that can be decoded that indicate horsepower rating. If not, we will need to inject that information as a metadata property either at logging or by reading an SQL database post logging. Once that is complete, we may then use the 'pump horsepower' property to build our asset model and properly organize pumps into their respective catagories.