Laurel

USB-to-RS485 Converter Board for Laurel Electronics 1/8 DIN Instruments

Features
Suitable for all 1/8 DIN Laureate DPMs, counters, timers & remote displays. Connects host meter to a computer via USB 2.0 while also acting as server for up to 31 Laurel device on an RS485 network.
Includes USB Type-B receptacle plus an RJ11 jack for connection to RS485 bus. Selectable baud rates to 19,200.
Powered by instrument. Isolated from meter and power grounds.
Description
The Laureate USB-to-RS485 Converter Board can connect up to 31 Laurel meters and counter on an RS485 bus to a computer wity a USB port. It features a USB Type-B connector for connection to a PC via a standard USB cable, plus an RJ11 jack for interface to an RS485 bus which can support up to 31 Laurel meters equipped with Laurel's RS485 interface board. That board features dual RJ11 connectors for RS485 daisy-chaining using commercial 6-wire RJ11 data cables, with no need for a hub.

The USB board is shipped with a driver on a mini CD ROM. That driver will will assign a COM port address to the connected USB device, which is then treated like an RS232 device, making the presence of the USB line transparent to the user and PC software. The individual meters, including the host meter, are selected in software by their own digital address, which can be entered from the meter front panel or by using Laurel's free Windows-based Instrument Setup Software.

Three serial protocols are user-selectable: Modbus RTU, Modbus ASCII, and Laurel ASCII. The Laurel ASCII protocol is the simplest and is recommended if Laureates are the only devices on the network. For more information, please see our Modbus Protocol Serial Communications Manual and our Serial Communications Manual. The Laurel Laurel ASCII protocol supports 31 device addresses, one of which needs to be the converter board. The two Modbus protocols support 247 device addresses; however, only 31 addresses can be electrically driven on an RS485 line without a repeater.

Multiple meters on an RS485 bus can also be digitally addressed using our Ethernet-to-RS485 converter board, which is normally connected to an Ethernet network router via an Ethernet line.

Installation
The Laureate USB-to-RS485 converter board provides a USB Type-B connector for a standard USB cable to a PC, RJ11 connector for connection to an RS485 bus with up to 31 Laurel meters and transmitters. The required USB cable is readily available in computer stores and also from Laurel as P/N CBL05.
USB & RJ11 connectors USB cable, P/N CBL05

Specifications

Electrical Specifications
Ethernet Board Specifications
Data rates 300, 600, 1200, 2400, 4800, 9600, 19200 bps
Devices per USB line 1 for host meter plus up to 31 on RS485 bus
USB connector USB Type-B receptable
USB compliance Universal Serial Bus Spec Revision 2.0, Full Speed
USB line length, max 5 m
Devices per RS485 line Up to 31
RS485 connector RJ11 jack
RS485 compliance EIA/TIA-485
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
Protocol Specifications (implemented on meter main board)
Modbus RTU
Standards Compliance Modbus over Serial Line Specification V1.0 (2002)
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, RS485 Modbus
Main Board Revision Level Level 5 or above
Modbus ASCII
Standards Compliance Modbus over Serial Line Specification V1.0 (2002)
Data Formats (selectable) 1. No parity, 7 data bits, 2 stop bits
2. Odd parity, 7 data bits, 1 stop bit
3. Even parity, 7 data bits, 1 stop bit
Applicable Interface Boards Ethernet, USB, RS232, RS485, Modbus RS485
Main Board Revision Level Level 5 or above
Laurel ASCII
Data Format No parity, 8 data bits, 1 stop bit
Protocol Laurel Laurel ASCII
Applicable Interface Boards Ethernet, USB, RS232, RS485, RS485 Modbus
Main Board Revision Level Any
Laurel Software Requiring a Communications Board
Instrument Setup Software runs on a PC and provides a Windows Graphical User Interface (GUI) as an alternative to programming the meter from the front panel. This software can be downloaded from this website at no charge. Its use requires a serial communications board in the meter, but following setup that board can be removed if desired. Compatible with Modbus or Laurel ASCII protocol.

Custom Curve Linearizing Software is compatible with the Extended option version of all Laureates. Not applicable to temperature. Custom curve linearization can provide exceptional accuracy from low cost transducers and extend their working range on the high and low ends. This software can be downloaded from this website at no charge. Meter setup requires a serial communications board in the meter and the Laurel ASCII protocol, but following setup that board can be removed if desired and any protocol can be used.

Data Logging Software turns a PC into a data logging system. The RS232 board allows data logging with a single meter. Use of RS485 boards allows data logging with up to 31 Laureate instruments. Data can be logged from selected meters into an ASCII file, which can then be imported into MS Excel. Data can also be displayed on the computer screen in the form of up to 64 actual or virtual panel meters in 4 groups (or screens) of up to 16 meters each. Compatible with Laurel ASCII protocol only.
5672 Bolsa Avenue Huntington Beach, CA 92649 - USA - Ph (714) 622-2000 - Fax (714) 622-2001