GE Industrial Solutions DV-300 DC Drive Users Manual - Manual (Page 56)

GEI-100332Ga
——— WIRING PROCEDURES ———
4
12
4.5 SERIAL INTERFACE
4.5.1 Description
The RS 485 serial interface enables data transfer via a loop made of two symmetrical, spiral conductors with a
common shield. The maximum transmission distance is 3936 feet (1200 m) with a transfer rate of 38,400 KBaud.
The transmission is carried out via a differential signal.
RS 485 interfaces are bus-compatible in half-duplex mode, i.e. sending and receiving take place in succession.
Up to 31 devices (up to 128 address selectable) can be networked together via the RS 485 interface.
Address setting is carried out via the Device address parameter. Further information concerning the parameters to be
transfered, their type and value range is given in the table contained in section 10, “Parameter List” (RS485 column).
The RS 485 on the DV-300 series devices is located on the Regulation card in the form of a 9-pole SUB-D socket
connector (XS).The communication may be with or without galvanic isolation: by using galvanic isolation an
external power supply is necessary for +5V. The differential signal is transferred via PIN 3 (TxA/RxA) and PIN
7 (TxB/RxB). Bus terminating resistors must be connected at the physical beginning and end of an RS 485 bus
in order to prevent signal reflexion. The bus terminating resistors on DV-300 series devices are connected via
jumpers S12 and S13. This enables a direct point-to-point connection with a PLC or PC.
1 2 3 4 11 12 13 20 21 22 23 24 25 26 27 28
1 2 3 4 11 12 13 20 21 22 23 24 25 26 27 28
R-TPD32-GE
33 34
33 34
XS
1 2
3
4 5
9 8 7 6
150 R
TxA/RxA
TxB/RxB
0 V S
+5 V S
S12 S13
PE
RS485
100
R
470
R
470
R
+5 V
S19
S18
Figure 4.5.1.1: RS485 serial interface
n
ote
! Ensure that only the first and last drop of an RS 485 bus have a bus terminating resistor
(S12 and S13 mounted). In all other cases (within the line) jumpers S12 and S13 must not
be mounted. With S18 and S19 mounted the drive supply the serial line. This modality is
allowed on point-to-point connection without galvanic isolation only.