Current loop devices use current on
or current off to transmit binary digits. B&B converters interface RS-232 and
RS-422/485 systems to the most common current loop ports, 20 mA ports with open
circuit voltages up to 30 V. Many models can be modified for higher loop
currents and voltages. Call B&B Electronics’ Technical Support Department for
details.
High speed optical isolators couple
and isolate transmit and receive data. All B&B current loop converters have a
transmit (T+ and T-) and a receive (R+ and R-) loop. Each loop may be operated
as an active or passive loop. When the converter needs to provide the loop
current, a 12 VDC power supply is required for the current loop side. Maximum
baud rate recommended for current loop converters is 19.2 kbps.
