The USB to Serial Adapter - Generally
A USB to serial adapter, also referred to as a USB serial converter or USB RS232 adapter is a small electronic device which can convert a USB signal to serial RS232 data signals. RS232 is the type which is in many older PCs and is referred to as a serial COM port.
A USB to serial adapter typically converts between USB and either RS232, RS485, RS422 or TCP signals, however some USB to serial adapter / USB RS232 serial converter designs have other special conversion features.
Even the USB to serial adapter RS232 standard is an older communication protocol it is still used by many modern USB to serial adapter devices in both business and consumer markets and is also often used for personal and office USB to serial adapter devices. More recently most new computers do not have a COM port so a USB serial adapter is often used to connect many types of devices. A USB to serial adapter is a very useful device for connecting equipment such as USB to serial adapter printers, scanners, scales and GPS devices, but also most USB to serial business and consumer equipment. A USB to serial adapter is typically either a RS232 USB serial adapter, a RS485 USB serial adapter or a RS422 USB serial adapter. Many new USB to serial adapter devices are today designed with a multiple USB to serial adapter RS232/RS485 and even USB to serial adapter RS422 interface, which makes it very convenient since you then can use it for both RS232 and RS485 products.
The USB serial adapter protocol has been around for many years and is a very reliable protocol. The USB serial adapter is usually used in industrial, office and business environments however also often as a consumer product for connecting USB serial products to personal computers. The RS485 USB to serial adapter is most often only used in industrial environments, labs and similar facilities since the RS485 USB to serial adapter protocol is very useful in these environments.
The USB to serial adapter is made in a variety of models and types, the standard non-isolated USB to serial adapter is most commonly used in business, office and laboratory environments. The isolated USB to serial adapter is often used in industrial environments due to its resistance to voltage spikes and ground loops.