Rs485 Serial Communication - Toshiba ME00070B Manual

CONTROL CIRCUITS
Start signal
Output voltage
RELAY FUNCTIONS
Main contactor
Start/Run
Run
Motor Thermistors
Motor thermistors (if installed in the motor) may be connected
directly to the TMS7. A trip will occur when the resistance of the
thermistor circuit exceeds approximately 2.8k . The TMS7 can
be reset once the thermistor circuit resistance falls below
approximately 2.8k
No motor thermistors
Motor thermistors
NOTE:
The thermistor circuit must be closed before the
TMS7 will run.
The thermistor circuit should be run in screened
CAUTION
cable and must be electrically isolated from earth
and all other power and control circuits.
If no motor thermistors are connected to the TMS7
thermistor input there must be a link across the
thermistor input terminals C1 & C2.

6.4 RS485 Serial Communication

The TMS7 has a non-isolated RS485 serial communication link.
RS485
GND
NOTE:
Power cabling should be kept at least 300mm away
from communications cabling. Where this cannot
be avoided magnetic shielding should be provided
CAUTION
to reduce induced common mode voltages.
Data transmitted to and from the TMS7 must be in 8 bit ASCII,
no parity, 1 stop bit.
Baud rate is set by Function. 61 RS485 Baud Rate.
The TMS7 can be programmed to trip if the RS485 link fails by
setting Function 60. RS485 Timeout.
The starter address is assigned using Function 62. RS485
Satellite Address.
The flow charts below show typical form of communication
between an TMS7 and host controller.
14
Pre-start Tests
C1
Thermistor Input
C2
C1
Thermistor Input
C2
C3
-
C4
+
C5
Host controller to TMS7
SE ND REQUEST
TI MEOUT
RE CE IVE DA TA
N DATA
RECI EVE D
N
LRC
VALID
Y
LRC
ERROR
TMS7 to host controller
DETECT
RECEIVE
ADDRESS
ADDRESS
SEND ACK
RECEIVE DATA
SEND DATA
The following code sequences are used in the communications
between the host and the TMS7 (network).
Address slave unit.
ASCII EOT [nn]
ENQ
or 04h [n1]h [n2]h
05h
Slave response.
ASCII ACK
or 06h
ME00070B
START
SEND TMS7
S LAV E ADDRES S
N
ACK
N
RECEIV ED TIMEOUT
Y
D C
DATA/
COMMA ND
SEND COMM AND
Y Y
TIME OUT
N
N
ACK
RECEIV ED
Y
Y
TIME OUT
E ND
ERROR
START
N
EOT
Y
N
N Y
EOT
ENQ
Y
N
L RC
VALI D
Y
N
VALI D
Y
N
N Y
STX EOT
Y
N
N Y
EOT
ETX
Y
N
L RC
SEND NAK
VALI D
Y
N
SEND
CONTROL TMS7
DATA
Y
SEND ACK
LRC
[LRC1]h [LRC2]h
Y
N
TMS7 SERIES