- 2 -
Front and Rear view
Side view
1. RS-232 Serial port (DB9F)
2. Power input terminal block
3. CAN-Bus Link/ACT LED
4. Serial port transmits and receives data LED
5. Power indicator
6. Wallmount screw hole
7. Equipment information
8. CAN-Bus port terminal block
9. DIP switch
【
Dimension
】
Unit (mm)
【
Power supply input
】
CAN232 interface converter provide DC power input, voltage
input is the two terminal form, plug type 2 core spacing of
5.08mm terminals, wherein the power input range of 9 ~ 48VDC.
The power support is not polarity that the device can still work
normally after the reverse.
【
DIP switch
】
The converter front panel provide 4 bit DIP switch to set function
(ON is effective). 1 and 4 keep for future function. 2 is for
configuration mode settings. 3 is recovery default factory. Please
power off and power on when you change the status of DIP
switch.
【
Communication connector
】
CAN-Bus interface
NO.
Name
Define
1
GND
Protective Ground
2
CANL
CANL Signal Line
3
CANH
CANH Signal Line
4
RES+
External Terminal Resistor (
+
)
5
RES-
External Terminal Resistor (
-
)
CAN terminals
While CAN232 device connects with the CAN-Bus network via
twisted pair, CANL connects with CANL, CANH connects with
CANH. According to the ISO11898 standard, to reduce signal
reflections on the CAN-Bus and enhance the reliability of
communication, terminal matching resistor is usually added to 2
endpoints of the bus. The size of terminal matching resistor is
decided by the characteristic impedance of cable transmission,
such as twisted pair’s characteristic impedance is 120
Ω, the 2
endpoints on the bus should be connected 120
Ω terminating
resistor. CAN232 can set external terminating resistor, when the
device is connected with the CAN-Bus network via a twisted pair,
only use resistor to short circuit between the twisted pair ports
RES+ and RES- to achieve terminal resistor accession, as shown
below.
