CONTROL CIRCUITS
TMS7 SERIES
ME00070B
15
CAUTION
NOTE:
If no TMS7 starter is configured to the specific
slave address, no response will be received by the
host. The host software timeout should be set to a
minimum of 250 ms.
CAUTION
NOTE:
Slave address must be two digit, addresses less
than 10 must have a leading zero (0).
Master command to slave.
ASCII STX
[command]
LRC
ETX
or
02h
[c1]h [c2]h [c3]h
[LRC1]h [LRC2]h
03h
[command] = 3 byte ASCII command (or request) selected from
the tables below.
LRC = Longitudinal Redundancy Check.
Slave response if Command and LRC correct
ASCII ACK
or
06h
Slave response if Command and LRC incorrect
ASCII NAK
or
15h
Slave response of Read request correct and LRC correct.
ASCII STX
[data]
LRC
ETX
or
02h
[d3]h [d2]h [d1]h [d0]h [LRC1]h [LRC2]h
03h
Slave response if Read request or LRC invalid.
ASCII NAK
or
15h
Each command, status or data request is a 3 byte string as
detailed below. Invalid command/request strings cause the
TMS7 to respond with a NAK (15h).
Command
ASCII
Comment
Start
B10
Initiates a start.
Stop
B12
Initiates a stop
Reset
B14
Resets a trip state
Coast to
stop
B16
Initiates an immediate removal of
voltage from the motor. Any soft
settings are ignored.
Status
Read
ASCII
Comment
Status
C10
Requests the configuration status of the
TMS7.
Status_1
C12
Requests the operational status of the
TMS7.
Trip
C14
Requests the trip status of the TMS7.
Version
C16
RS485 protocol version number.
Trip Code
C18
255 = No trip
0 =
Shorted SCR
1 =
Reserved
2 =
Motor Thermal model trip
3 =
Motor thermistor
4 =
Current imbalance trip
5 =
Supply frequency trip
Status
Read
ASCII
Comment
6 =
Phase rotation trip
7 =
Stall trip
8 =
Power circuit fault
9 =
Undercurrent trip
10 =
Starter heatsink
overtemperature
11 =
Invalid motor connection
Data Read
ASCII
Comment
Current
D10
Requests motor current. The data is 4
byte decimal ASCII. Minimum value
0000, Maximum value 9999 Amps.
Temp
D12
Requests the calculated value of the
motor thermal model as a % of Motor
Thermal Capacity. The data is 4 byte
decimal ASCII. Minimum value 0000%.
Trip point 0105%.
Each command string sent to and from the TMS7 includes a
check sum. The form used is the Longitudinal Redundancy
Check (LRC) in ASCII hex. This is an 8-bit binary number
represented and transmitted as two ASCII hexadecimal
characters.
To calculate LRC:
1.
Sum all ASCII bytes
2.
Mod 256
3.
2's complement
4.
ASCII convert
For example Command String (Start);
ASCII
STX
B
1
0
or
02h
42h
31h
30h
ASCII
Hex
Binary
STX
02h
0000 0010
B
42h
0100 0010
1
31h
0011 0001
0
30h
0011 0000
A5h
1010 0101 SUM (1)
A5h
1010 0101 MOD 256 (2)
5Ah
0101 1010 1's COMPLEMENT
01h
0101 1011 + 1 =
5Bh
0101 1011 2's COMPLEMENT (3)
ASCII 5
B
ASCII CONVERT (4)
or
35h
42h
LRC CHECKSUM
The complete command string becomes
ASCII STX
B
1
0
5
B
ETX
or
02h
42h
31h
30h
35h
42h
03h
To verify a received message containing an LRC;
1.
Convert the last two bytes of message from ASCII to
binary.
2.
Left shift 2
nd
to last byte 4 bits.
3.
Add this result to the last byte to get the binary LRC.
4.
Add up all the bytes of the message, except the last two.
5.
Add the binary LRC.
6.
The least significant byte should be zero.
For example:
ASCII
STX
B
1
0
5
B
ETX