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Diamond Point International

B&B Inline USB to Serial Converters - 1 Port Versions

Add a single RS-232 or RS-422/RS-485 ports to your PC


These compact, isolated USB to RS-232 and USB to RS-422, and RS-485 converters allow you to add an asynchronous serial port to your USB only PC. The built in 2 kV isolation protects your port from dangerous ground loops. They are perfect for connecting to remote devices or programming ports in field service applications. They are USB 2.0 compatible. Model USO9ML2 is the RS-232 version and supports hand shake signals as well as data at speeds up to 460.8 Kbps. Model USOPTL4 is the RS-422 and RS-485 version and supports data rates up to 460.8 Kbps. RS-485 2-Wire and 4-Wire modes are selected using a DIP Switch. If you don’t need isolation, use model USPTL4. Windows operating systems up to Windows 8 (32 and 64 bit) are supported. The USOPTL4 is equipped with our signature high retention USB port. The RS-422/485 versions have a removable terminal block

Locked Serial Number Facility

To better support field service pools, B&B created “LS” versions of these popular converters. Simply put, “LS” stands for “Locked Serial Number.” Units that are programmed with the “locked serial number” are field service friendly in that they all share the same serial number. This feature allows for a single driver installation – if you plug another “LS” version of the same model number into your PC, it will be assigned to the same COM port. With the standard version each time you install a product with the same model number, you must go through the driver installation and it will be assigned to a unique COM port.



InterfaceRS-232: TD, RD, RTS, CTS, DTR, DSR, DCD, GND
RS-422/485 4-Wire: TDA(-), RDA(-), TDB(+), RDB(+), GND
RS-485 2-Wire: DATA A(-), DATA B(+), GND
Isolation: 2 kV (all versions)
Data RatesData Rate: 460.8 Kbps (all versions)
USBUSB Technology
• USB Compatibility: 1.1 and 2.0 (at full speed)
• Speed: 12 Mbps (Full)
OtherIndicators: TD / RD (RS-232): Red LED
Connector(s)RS-232 Connector: DB9 Male
RS-422/485 Connector: Terminal block
RS-232 USB Connector: Type B
RS-422/485 USB Connector: Type B Type B High Retention (15 N / 3.4 lbs-force withdrawal)
Power Connector: Terminal Block or Locking Barrel Plug


ElectricalSource: USB Bus Powered
Power Consumption: Low Power Device (Less than 100 mA)
MechanicalRS-232: 7.7 x 4.3 x 2.3 cm (3.0 x 1.7 x 0.9 in)
RS-422/485: 8.9 x 4.3 x 2.1 cm (3.5 x 1.7 x 0.8 in)
Enclosure IP 30, Plastic
SoftwareWindows 2000, XP (32/64 bit), Vista (32/64 bit),
Windows 7 (32/64 bit), 8 (32/64 bit),
2003 & 2008 Server (32/64 bit)
TemperatureTemperature range (operation): 0 to +70°C
Temperature range (storage): -40 to +80°C
Humidity0 to 95% Non-condensing
Weight6.4 oz (0.18 kg)
MTBFMTBF USO9ML2: 247,713 hours
MTBF USOPTL4: 311,327 hours
MTBF USPTL4: 1,012,584 hours
Safety/CertificationEN 55022: 2010 + AC:2011 Class B Emissions
EMCEN 61000-6-1:2007 Generic Standards for Residential, Commercial and Light-Industrial Environments
EN 61000-4-2: 2009 Electro-Static Discharge (ESD)
EN 61000-4-3: 2006 +A1 +A2 +IS1 Radiated Field Immunity (RFI)
EN 61000-4-4: 2012 Electrical Fast Transients-Burst Immunity (EFT
EN 61000-4-6: 2009 Conducted Immunity

Ordering Details

BoardUSOPTL4 USB To Isolated 422/485 W/Plug Term Block And Leds
USOPTL4-LS USB To Isolated 422/485 TB , Leds - Locked Serial #

USPTL4 USB To 422/485 With Pluggable Term Blocks And Leds
USPTL4-LS USB To RS-422/485 TB , Leds - Locked Serial #

USO9ML2 USB To Isolated RS-232 DB9-M
USO9ML2-LS USB To Isolated RS-232 DB9M - Locked Serial #
AccessoriesTB5P508SR-2PK 5 position terminal block with strain relief paddle board, 2 pack
9PAMF6 DB9 Male To DB9 Female, 6 Ft
Order Online B&B Inline USB to Serial Converters - Order Online