From our pump flow meters we collect total gallons over time and that number gets pretty big. Currently it’s at 3,713,041 gallons. I want to convert that to acre/ft. It’s an easy conversion that I know how to do. My problem is making it work in the Opto/Node-RED environment.

Here’s the formula: 1 gallon = 0.0000030688832459704 acre/ft

Here’s my issue:

- Groov will display the raw number if I make the tag a float. However I don’t know how to use the scaling function in Groov to do make the conversion. As you can see it’s simple multiplication.
- I tried to do it in Node-RED thinking I could use a Function node and write a simple script but NR reads the Modbus device that stores it as two numbers in two consecutive registers and I don’t know how to covert those to a single number so my simple little multiplication will work.

The numbers in question are:

Total Gallons: 3713041

Low register: 19042

High register:41028

Any help would be appreciated.

Thanks