Dax sum / filter when match

Hi everyone,

I have a question regarding a DAX formula. I want to run a calculation when values from 2 different tables, without relationship, match.

In Table A, the column used is Code-A.
In Table B, the column used is Serial Code

What I have so far:

Measurename = 
CALCULATE (
         SUM ('Fact'[Balance]);
         FILTER ('Table B'; [Serial-Code] = "1234")
     )

In conclusion, I would like something as follows:

Measurename = 
CALCULATE (
         SUM ('Fact'[Balance]);
         FILTER ('Table B'; [Serial-Code] = 'Table A'; [Code-A])
     )

Unfortunately, I have not managed to get this working. I hope somebody can help me with this.

Again: The tables do not have a relationship / join.