@kll The OP is encoding his three sensor data in a single field. Each digit would represent a value related to each sensor’s state. He is working with base 10 meaning that each digit is extracted based on powers of 10.
@KeirMeDear One solution is to use 0,1,2 instead of 1,0,3. When you encode your values into a single field, all possible values will be below the 255 limit as kll discussed in his post. Another solution is to use a lower base. You are using base 10. You could do base 3 as you only have 3 values. It is more work and it would be a good exercise if you want to try something different.
Kf