Wavetronix SmartSensor 105 (SS-105) - User Guide - Manual (Page 98)

APPENDIX • SMARTSENSOR 105 USER GUIDE 97
1400–2000 ft.
(426.7–609.6 m) Alternate power and
communications cable Native RS-485 Click conversion of
RS-485 to RS-232
Table C.3 – Cable Length Options
Appendix D – Direct Serial Connections
For most applications, the service end of the SmartSensor cable terminates in a surge pro-
tection device. However, during demonstrations, troubleshooting, and certain other situ-
ations, it is sometimes convenient to bypass surge protection and connect directly to a
personal computer or communications device such as a modem.
The sensor is configured as an RS-232 DTE device. To connect the SmartSensor cable’s
RS-232 wires directly to another DTE device (such as a PC), you can use a standard 9-pin
“D” connector and a null modem cable. To connect directly to a DCE device (such as a
modem), you will need a straight-through cable. Figure D.1 illustrates both of these cases.
SmartSensor
Connector
Power Wires
RS-485 Wires
Null Modem Cable
Straight-through Cable
or
DTE Device (PC)
DCE Device (Modem)
Figure D.1 – Direct Serial Connections
Note
If you do not have the right type of RS-232 physical connection you will not be able
to connect using the SmartSensor Manager software. Since null modem cables and
straight-through cables look similar, you may want to label them. Alternatively, you
may want to use a null modem adapter instead of a null modem cable. If you do, you
can turn your straight-through cable into a null modem cable by attaching the adapter
on one end.