Remember that an RS232 port is NOT p'n'p so if there is any interruption then problems could be had.
You have learnt SW from Corona688 and HW pitfalls from me.
The real world is that your connection may be interrupted by a third party event beyond your control, (example a major underground cable assembly being damaged during roadworks), which shuts you off from access to the remote scales...
Not sure how you are going to cater for long time interruptions unless you can get the scales to store its data locally then do a dump to your machine when everything returns back to normal...
BTW these tests should initially be done locally before even attempting ANY remote tests.
This is a good starting point to find out more about the old serial port:-
RS-232 - Wikipedia, the free encyclopedia