Current loop devices use current on or current off to transmit binary digits. B&B Electronics 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.

High speed optical isolators couple and isolate transmit and receive data. All B&B Electronics 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.

Models 232CL9R and 232CL4R are port powered RS-232 to current loop converters. No external power required for passive loop installations. A power supply is required to generate an active loop.

Model 232PCLR is an RS-232 to current loop converter that requires a power supply for the RS-232 side of the converter. Model 485CL is a 2-channel RS-485 or RS-422 to current loop converter with Automatic Send Data Control. It requires a power supply for the RS-485/422 side of the converter. (Power supplies not included.)

Features

• All models are optically isolated
• Designed for 20 mA. Inquire about other values
• Maximum baud rate: 19.2 kbps