Kahn Optidew Bench Top, User Manual

Page: 19 / 88

Optidew User’s Manual
10 October 2019
INSTALLATION
The fuse is rated at 5 x 20mm medium acting:
Power 230 V AC 2.5 A
A replacement fuse can be obtained by contacting Kahn Instruments Service Department.
Equipment Ratings
This product is designed to be safe at least under the following conditions: between a
temperature range of -40°F/C to +140°F/+60°C, in maximum 80% relative humidity
for temperatures up to +88°F/+31°C decreasing linearly to 50% RH at +122°F/+50°C.
Overvoltage Category II. Pollution Degree 2. Altitudes up to 2000m. Indoor use only but
an IP65 unit is offered as an option.
See Appendix A, Technical Specification, for full operating parameters.
2.3.2 Analog and Digital Communications
Note: When using screened cable, the screen should only be connected to a ground
point at either the Optidew installation side, or at the receiving equipment. Failure to
observe this precaution can result in ground loops and equipment malfunction.
2.3.2.1 Digital Communications
Figure 10
RS485 & analog output connector
The leftmost four pins of this connector are used for RS485 communications.
Pin Label Description
GND Ground
RS485 A
RS485 Data A
RS485 B RS485 Data B
GND Ground
The Optidew provides Modbus RTU over RS485 or USB (Bench Top only). An Ethernet
module is optionally available for both instruments, and provides Modbus TCP
communication.
The Modbus register map can be found in Appendix B.
The application software provided can be used to communicate with the instrument.