The Laureate RS232 serial communication board allows a Laureate 1/8 DIN digital panel meter, counter or timer to be interfaced to an external PC, a serial input remote display, or other device. Connection to a PC allows programming via Laurel's free Windows-based Instrument Setup Software, or to output readings to a PC for display and datalogging using Laurel's free XLOG2 software.
RS232 is normally only used for point-to-point communications via a single data line. The RS232 request-to-send line (RTS) can be set to a latched mode, where a single reading is transmitted when the line is taken high momentarily. This mode allows a single data transfer to be commanded by another device.
RS232 can drive a 6-digit Laureate remote display or a Serial Input MAGNA large digit display. These units can use the received RS232 datat to display readings, to switch relays for alarm or control, and to generate a scaled analog output, such as 4-20 mA or 0-10V. Two Laureate 6-digit remote displays can be connected to a single RS232 line in multidrop fashion and be digitally addressed.
If multiple meters are to be digitally addressed by a PC or PLC, use our RS485, USB, Ethernet or WiFi boards, as listed in Laurel's communication board selection page.
Two serial protocols are user-selectable for RS232: Modbus RTU and Custom ASCII. Modbus RTU is an international Master-Slave protocol which works in a Query-Response command mode, and it requires use of an external Modbus Master. The text string based Custom ASCII protocol is the simpler of the two and is recommended if the Laureate is the only instrument on the data line, as would normally be the case with RS232. It can be set to a command mode or a continuous data streaming mode to send serial data in the absence of an external Master. For information on our protocols, please see our communication user manuals.
CBL01 cable assembly. Includes DB9 and RJ11 connectors to connect a Laureate with an RS232 board a PC RS232 COM port. Plugging into the Laureate is the RJ11 connector of a common 6-wire data cable. Plugging into the COM port of a PC is custom-wired DB9-to-RJ11 adapter, which accepts the other end of the 6-wire data cable. The DB9-to-RJ11 cable assembly is sold by Laurel as P/N CBL01.
CBL02 USB-to-RS232 adapter. Includes USB and DB9 connectors. Combined with a CBL01 cable (illustrated), it allows a Laureate meter with an RS232 board to be connected to a PC USB port. Note that Laurel also offers a USB board, which allows a Laureate meter to be connected to a PC USB port using a standard USB cable.
|RS232 Board Specifications|
|Laurel Part Number||L232||Connection||RX, TX, GND, RTS (optional)|
|Data Rates||300, 600, 1200, 2400, 4800, 9600 baud|
|No. of Devices on Data Line||1 (point-to-point)|
|Connector||Single RJ11 jack|
|Line Length, Max||50 to 1000 ft (15 to 300 m) depending on cable and data rate|
|Isolation||250V rms working, 2.3 kV rms per 1 min test|
|ESD Protection||15 kV per IEC 1000-4-2|
|EMI Immunity||10 V/m per IEC 1000-4-3|
|EFT Protection||2 kV per IEC 1000-4-4|
|Short Circuit Protection||Continuous|
|Selectable Protocols||Modbus RTU, Custom ASCII.|
|Standards Compliance||Modbus over Serial Line Specification V1.0 (2002)|
|Protocol Type||Master-slave, query-response command mode|
|Data Streaming Mode||Not supported by Modbus specification|
|Data Formats (selectable)||1. No parity, 8 data bits, 2 stop bits|
|2. Odd parity, 8 data bits, 1 stop bit|
|3. Even parity, 8 data bits, 1 stop bit|
|Applicable Interface Boards||Ethernet, USB, RS232, RS485|
|Conversion to Modbus TCP||Automatic for Ethernet|
|Main Board Revision Level||Level 5 or above|
|Standards Compliance||Laurel proprietary protocol|
|Data Format||No parity, 8 data bits, 1 stop bit|
|Protocol Type||Text string based command mode or continuous data streaming mode|
|Data Streaming Mode||User selectable for up to 60 readings/sec|
|Applicable Interface Boards||RS232, RS485, USB|
|Main Board Revision Level||Any|