Sensor Wiring
76
Modline 5
Sensors should be wired in tandem as shown in the diagram. The RS-485 terminals from the Sensor
furthest from the host device are wired to the next closest Sensor. Then the RS-485 Terminals of that
Sensor should be wired back to the next closest sensor. Do this until all sensors are wired. Do not use
any other configuration.
A 120 ohm termination resistor should be placed across the RS-485 terminals of the Sensor furthest from
the Host device as shown in the diagram. Consult the manual for the Host device to determine if any
termination resistor is required at its terminals. The IRCON Model MSI Interface does not require a
termination resistor at its input.
To maintain signal integrity and reduce noise pick-up, twisted pair shielded cables with overall foil and
braid shielding should be used for connecting to all Sensor inputs and outputs. Belden low capacitance
computer cable types 9829, 9830, 9831, 9832, 9839 and 9833, or equivalent cables are recommended. Each
of these cables has a different number of wire pairs varying in quantity from 2 to 7 pairs.
The cable selected should have a twisted pair nominal impedance of 100 ohms and nominal capacitance
between conductors should not exceed 15.5 pF/ft. (50.9 pF/m).
Select power supplies and install cables as instructed in previous sections of the
manual.
Figure 68
4.9.1
Computer Communications Requirements
The Host device communicating with The Modline 5 Sensor should have an RS-485 communication
port. If not, an RS-232 Port and a RS-485 to RS-232 converter can be used. An RS-485 to USB converter
can also be utilized. The combined communications port and converters used must have the capability
to communicate over a 2 wire, half duplex RS-485 network at
speeds fast enough to handle command
requests with reply turnaround times of one-millisecond or less
.
The following converters will provide satisfactory performance when used with Modline 5 Sensors.
To Sensors
RS-485 Multi-drop Network
Ground TX-A TX-B
RS-485 Serial Port
IRCON Multiple Sensor Interface (MSI)
or PC, PLC, Control System
Sensors with TSP Terminal Strip Plates
Power Supply
More than one
Required,
see Manual
