Problem: The RS232 commands of the incubator are most likely proprietary, meaning that there is no documentation about the commands whatsoever.
Why assume that? Since we're talking about lab equipment that often needs to be integrated into setups the manufacturer hasn't anticipated, there's actually a decent chance that the interfaces are published so people can write their own apps using systems like Labview. Have you done google searches on the make and model, or checked the manufacturers' websites?
If you do need to reverse-engineer the protocol, I recommend you grab an old unused PC with 2 serial ports, put Linux on it, and use scope
to monitor the traffic. It's free, easy to set up, and makes it simple to capture the traffic to a text file so you can pore over it at your leisure.