Terminating Resistor; Indications; Connection With The Rs485 Network; Usb Communication Module (Cfw320-Cusb) - WEG CFW320 User Manual

It allows the connection of up to 32 devices to the same segment. More devices can be connected by using
2
repeaters .
A maximum bus length of 1000 meters.

2.1.3 Terminating resistor

It is necessary to enable a terminating resistor at both ends of the main bus for each segment of the RS485 network.
If the equipment located at both ends of the bus does not have termination resistors, use active terminating to enable
these resistors.

2.1.4 Indications

Details on the alarms, communications failures and communication states are made through the keypad (HMI) and
product parameters.

2.1.5 Connection with the RS485 Network

The following points must be observed for the connection of the device using the RS485 interface:
It is recommended the use of a shielded cable with a twisted pair of wires.
It is also recommended that the cable has one more wire for the connection of the reference signal (GND). In case
the cable does not have the additional wire, then the GND signal must be left disconnected.
The cable must be laid separately (and far away if possible) from the power cables.
All the network devices must be properly grounded, preferably at the same ground connection. The cable shield
must also be grounded.
Enable the termination resistors only at two points, at the extremes of the main bus, even if there are derivations
from the bus.

2.2 USB COMMUNICATION MODULE (CFW320-CUSB)

For this module, a USB interface with mini-USB conector is available. When connecting the USB interface, it will
be recognized as a USB to serial converter, and a virtual COM port will be created
with the drive via this COM port.
2
The limit of devices that can be connected on the network depends on the protocol used.
3
It is necessary to install the USB driver on the CD-ROM supplied with the product. The COM port number created depends on the availability
in the operating system and, once connected, consult the hardware resources of the system to identify this port.
Table 2.2: Configuration of the switches to configure the RS485
Switch Setting
S1.1 = OFF and S1.2 = OFF
S1.1 = ON and S1.2 = ON
S1.1 = OFF and S1.2 = ON
S1.1 = ON and S1.2 = OFF
Figure 2.2: Module with USB connection
Option
RS485 Termination off
RS485 Termination on
This combination is not allowed
3
INTERFACE DESCRIPTION
. Thus communication is made
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