Why is putty hanging?

Question

SSH

Good afternoon. There is a problem. There is a certain amount of network equipment and a cable for configuring it (a standard console cable like in Tsiska) and an rs-232-usb adapter. The bottom line is that at a random moment the connection freezes and does not respond to anything (disconnecting from the computer does not help, the system itself freezes (cannot turn off))
From the equipment: allied telesis network equipment, pl2303 rs232-usb adapter and a standard console cable .