Gs2 PDF

GS2 MODBUS CHAPTER
COMMUNICATIONS
5
In This Chapter...
Communication Parameters Summary . . . . . . . . .5–2
GS2 Status Addresses . . . . . . . . . . . . . . . . . . . . .5–4
Communicating with DirectLogic PLCs . . . . . . . .5–5
Communicating with Third-party Devices . . . . .5–16
Chapter 5: GS2 MODBUS Communications
Communication Parameters Summary

A summary of the GS2 Communications Parameters is listed below. For a
complete listing of the GS2 Parameter, refer to CHAPTER 4.
Communications
GS2
Description Range Default
Parameter
P 9.00 Communication Address 01 to 254 01
00: 4800 baud
01: 9600 baud
P 9.01 Transmission Speed
02: 19200 baud
01
03: 38400 baud
00: MODBUS ASCII mode

7 data bits,no parity,2 stop bits
7 data bits,even parity,1 stop bit
7 data bits,odd parity,1 stop bit
P 9.02 Communication Protocol
03: MODBUS RTU mode
00
8 data bits,no parity,2 stop bits
04: MODBUS RTU mode
8 data bits,even parity,1 stop bit
05: MODBUS RTU mode
8 data bits,odd parity,1 stop bit
00: Display fault and continue operating

01: Display fault and RAMP to stop
P 9.03 Transmission Fault Treatment 02: Display fault and COAST to stop 00
03: No fault displayed and continue
operating
00: Disable
P 9.04 Time Out Detection
01: Enable
00
P 9.05 Time Out Duration 0.1 to 60.0 seconds 0.5

00: All parameters can be
쏆 P 9.07 Parameter Lock set and read 00
01: All parameters are read-only
99: Restores all parameters to factory
P 9.08 Restore to Default
defaults
00
쏆 P 9.11 Block Transfer Parameter 1 P 0.00 to P 8.01 P 9.99

5–2 GS2 Series AC Drive User Manual

Communication Parameters Summary (cont.)

Communications
GS2
Description Range Default
Parameter
쏆 P 9.26 RS485 Speed Reference 0.0 to 400.0 Hz 60.0
쏆 P 9.27 RUN Command 00: Stop 01:Run 00
쏆 P 9.28 Direction Command 00: Forward 01:Reverse 00
쏆 P 9.29 External Fault 00: No fault 01:External fault 00
쏆 P 9.30 Fault Reset 00: No action 01:Fault Reset 00
쏆 P 9.31 JOG Command 00: Stop 01:Jog 00
01: GS1
02: GS2
P 9.41 GS Series Number ##
03: GS3
04: GS4
00: GS2-20P5
(230V 1ph/3ph 0.5HP)
01: GS2-21P0
(230V 1ph/3ph 1.0HP)
02: GS2-22P0
(230V 1ph/3ph 2.0HP)
03: GS2-23P0
(230V 1ph/3ph 3.0HP)
04: GS2-25P0
(230V 3ph 5.0HP)
05: GS2-27P5
(230V 3ph 7.5HP)
P 9.42 Manufacturer Model Information 06: Reserved ##
07: GS2-41P0
(460V 3ph 1.0HP)
08: GS2-42P0
(460V 3ph 2.0HP)
09: GS2-43P0
(460V 3ph 3.0HP)
10: GS2-45P0
(460V 3ph 5.0HP)
11: GS2-47P5
(460V 3ph 7.5HP)
12: GS2-4010
(460V 3ph 10HP)
쏆 Parameter can be set during RUN Mode.
GS2 Series AC Drive User Manual 5–3

GS2 Status Addresses

The GS2 Series AC drive has status memory addresses that are used to monitor the
AC drive. The status addresses and value definitions are listed below.
Status Addresses (Read Only)

Status Monitor Memory Address 2100H
Error Codes:
00: No fault occurred
01: Over-current(oc)
02: Over-voltage(ov)
03: Overhear (oH)
04: Overload (oL)
05: Overload 1 (oL1)
06: Overload 2 (oL2)
07: External Fault (EF)
08: CPU failure 1 (CF1)
11: Hardware Protection Failure (HPF)
12: Over-current during accel (OCA)
13: Over-current during decel (Ocd)
14: Over-current during steady state (Ocd)
15: Ground fault or fuse failure (GFF)
16: Low voltage (Lv)
17: Input power 3-phase loss
18: External Base-Block (bb)
19: Auto adjust accel/decel failure (cFA)
20: Software protection code (codE)
Frequency Command F (XXX.X) Memory Address 2102H
Output Frequency H (XXX.X) Memory Address 2103H
Output Current A (XXX.X) Memory Address 2104H
DC-BUS Voltage d (XXX.X) Memory Address 2105H
Output Voltage U (XXX.X) Memory Address 2106H
Power Factor Angle Memory Address 210AH
Software Version Memory Address 2110H

Communicating with DirectLOGIC PLCs

The following steps explain how to connect and communicate with the GS2
Series AC drives using DirectLOGIC PLCs.
Step 1: Choose the Appropriate CPU.

The GS2 Series AC drives will communicate with the following DirectLOGIC
CPUs using MODBUS communications.
• DL05 • DL06 • DL250
• DL260 • DL350 • DL450
Step 2: Make the Connections

First you must decide what type of interface will work best for your application.
The GS2 Comm Port can accomidate an RS232C or an RS 485 connection.
RS-232C
An RS-232C connection is somewhat limited. The maximum network cable length for
an RS-232C connection is 15 meters (50 feet). In addtion, using the RS-232C interface
will allow you to connect only one AC drive to one PLC. For and RS-232C
connection, set the GS2 DIP switches SW2 and SW3 to RS232.
RJ-11 Serial Comm Port RS485
RS-232C Interface Switches SW2 and SW3
2: GND must be set to RS232 for
3: RXD
6 1 an RS-232C connection.
4: TXD SW3 SW2
5: +5V RS232
Use the following wiring diagrams to connect your DirectLOGIC PLC to a GS2
Series AC drive with an RS-232C interface.
DL05: RS-232C Connection Wiring
DL05 GS2
PORT 2 Comm Port
1 0V 2 GND
3 RXD 4 TXD
DL250: RS-232C Connection Wiring
4 TXD 3 RXD
DL350/DL450
PORT 1 GS2
1
Comm Port
DL250: RS-232C Connection Wiring 2 TXD 3 RXD

3 RXD 4 TXD
DL250 GS2 5 CTS 2 GND
PORT 2 Comm Port 4 RTS
6 2 TXD 3 RXD 7 GND
1
3 RXD 4 TXD
25
5 CTS 2 GND
4 RTS
15 7 GND

RS-485
An RS-485 network cable can span up to 1000 meters (4000 feet). However, most
DirectLOGIC PLCs require an FA-ISONET (RS 232C to RS422/485 network adapter)
in order to make this type of connection. For an RS-485 connection, set the GS2 DIP
switches SW2 and SW3 to RS485.
RS-485 Interface Switches SW2 and SW3
3: SG-
6 1 an RS-485 connection.
4: SG+ SW3 SW2
5: +5V RS232
Use the following wiring diagrams to connect your DirectLOGIC PLC to a GS2
Series AC drive with an RS-485 interface.
Note: If an FA-ISONET module is used in your connection, make sure the jumpers are
set for RS485 communications.
DL05: RS-485 Connection Wiring GS2

DL05 Comm Port
2 GND
PORT 2 1 0V 1 0V GND
4 SG +
3 RXD 4 TXD TXD+
3 SG –
4 TXD 3 RXD TXD -
5 RTS 2 CTS RXD -
RXD+
FA-ISONET
DL250: RS-485 Connection Wiring GS2

DL250 Comm Port
PORT 2 2 GND
2 TXD 3 RXD GND
6 4 SG +
1
3 RXD 4 TXD TXD+
3 SG –
5 CTS TXD -
4 RTS 2 CTS RXD -
15 7 GND 6 GND RXD+
FA-ISONET
DL350/DL450 DL350/DL450: RS-485 Connection Wiring

GS2
PORT 1
1
Comm Port
2 GND
2 TXD 3 RXD GND
4 SG +
3 RXD 4 TXD TXD+
3 SG –
5 CTS TXD -
4 RTS 2 CTS RXD -
7 GND 6 GND RXD+
25 FA-ISONET

Step 3: Set AC Drive Parameters

The following parameters need to be set as shown in order to communicate
properly.
P 3.00: 03 or 04 – Operation Determined by RS232C/RS485 interface. Keypad STOP
is enabled (03) or disabled (04).
P 4.00: 05 – Frequency determined by RS232/RS485 communication interface
P 9.00: xx – Communication address 1-254 (unique for each device, see P 9.00)
P 9.01: 01 – 9600 baud data transmission speed
P 9.02: 05 – MODBUS RTU mode <8 data bits, odd parity, 1 stop bit>
Note: The previous list of parameter settings are the minimum required to communicate
with a DirectLOGIC PLC. There may be other parameters that need to be set to meet
the needs of your application.
Step 4: Configure the DirectLOGIC CPUs

The DirectLOGIC CPUs must be configured to communicate with the GS2 Series
AC drives. This set up includes setting up the communication port and adding
instructions to your logic program.
The set up for all of the DirectLOGIC CPUs is very similar. However, there may
be some subtle differences between CPUs. Refer to the appropriate CPU User
Manual for the specifics on your DirectLOGIC CPU.
Note: For instructions on MODBUS Configuration for your specific CPU, refer to the
appropriate CPU User Manual.

DirectLOGIC MODBUS Port Configuration

The following configuration example is specific to the DL250 CPU. Refer to the
appropriate CPU User Manual for the specifics on your DirectLOGIC CPU.
• In DirectSOFT, choose the PLC menu, then Setup, then “Secondary Comm Port”.
• From the Port list box, choose “Port 2”.
• For the protocol, select “MODBUS”.
• In the Timeout list box, select “800 mS”.

• Response Delay Time should be “0 mS”.
• The Station Number should be set to “1” to make the DL250 CPU a MODBUS master.
Note: The DL250 network instructions used in Master mode will access only slaves
1 to 90. Each slave must have a unique number.
• The Baud Rate should be set at “9600”.

• In the Stop Bits list box, choose “1”.
• In the Parity list box, choose “Odd”.

DirectLOGIC MODBUS Ladder Programming

The set up for all of the DirectLOGIC CPUs is very similar. However, there may
be some subtle differences between CPUs. Refer to the appropriate CPU User
Manual for the specifics on your DirectLOGIC CPU.
The following ladder program shows some examples of how to control the GS2
AC drive through MODBUS RTU. The drive should be setup and tested for
communications before it is connected to a load.
WARNING: A drive should never be connected to a load until any applicable
communication programs have been proven.
Note:This program is for illustration purposes only and not intended for a true application.
In many drive applications, electromagnetic interference can at times cause

frequent, short duration communication errors. Unless the application
environment is perfect, an occasional communication error will occur. In order to
distinguish between these non-fatal transients and a genuine communication
failure, you may want to use the instructions as shown in Rungs 1 through 4.
Rung 1 monitors the number of times that the PLC attemts to communicate with the
AC drive. When the PLC’s communication attempts are successful, SP116 will count
up and SP117 will not count. Once the count reaches 9999, the counter will reset
and resume counting.
DirectSOFT
SP116 CNT
1 Comm transaction count
CT0
_FirstScan
SP0 K9999
Comm transaction count

CT0
Note: SP116 and SP117 are special relays in the DirectLOGIC CPUs that monitor the
PLC’s commnunications. SP116 is on when Port 2 is communicating with another
device. SP117 is on when Port 2 has encountered a communication error.
(Cont. next page)

DirectLOGIC MODBUS Ladder Programming (cont.)

Rungs 2 through 4 monitor the number of times the PLC fails in communicating with
the AC drive. These instructions set the C50 bit (to be used for alarm or shut-down)
based on the number of times the SP117 bit is active in one minute. In this example
the C50 bit will be set if the number of errors exceed 20 in one minute.
SP117 CNT
2 Comm error count
CT1
_FirstScan
SP0 K20
_1Minute
SP3
Comm error count Drive comm error

CT1 C50
3 ( SET )
Clear errors Drive comm error
X5 C50
4 ( RST )
Block Transfer
There is a group of block transfer parameters available in the GS2 AC drive (P 9.11 to
P 9.25). This contiguous block of parameters can be used to "group" miscellaneous
parameters throughout the drive. This will allow you to update these miscellaneous
parameters in one block instead of having to use multiple WX or RX commands.
For example: If you need to change the PID setpoint (P 7.11), accel time (P 1.01),
decel time (P 1.02), and multi-speed 1 (P 5.01), this would typically take three
different WX commands because the parameters are non-contiguous. If you set
P 9.11 to P 7.11, P 9.12 to P 1.01, P 9.13 to P 1.02, and P 9.14 to P 5.01, then all of
these parameters could be controlled using one WX command.
Rung 5 writes the values from V2000 to V2023 to the drive parameters P 9.11 to
P 9.25. In the WX box, the value is V4413. 4413 is an octal number like all addresses
in the DirectLOGIC PLCs. If you convert 4413 octal to hex, you get 90B. 90B is the
address for parameter P 9.11.
Note: Refer to your PLC User Manual for more specifics on MODBUS addressing and
address conversions.
(Cont. next page)


If you only want to control the start/stop and speed reference of the drive, simply
change the second LD command of this rung to K4 and WX command to V4432.
Then V2000 would be your speed reference location and V2001 would be your
start/stop location.
SP116 C100 LD
5 Kf101
LD
K40
LDA
O2000
WX
V4413
C100
( SET )
Rung 6 is used to read the status of the GS2 AC drive. These instructions read the
values from the GS2 status addresses, 2100 to 2105, and places the values into
the PLC memory addresses, V3000 to V3005.
Notice the number in the RX box - V20400. 20400 is an octal number as are all
address references in the DirectLOGIC PLCs. 20400 octal converted to hex gives
you 2100 - the first status address for the GS2 AC drive.
SP116 C100 LD
6 Kf101
LD
K12
LDA
O3000
RX
V20400
C100
( RST )

Alternate MODBUS Ladder Programming

The Read and Write commands for the DL260 and DL06 CPUs are different from
other DirectLOGIC CPUs. Rungs 5 and 6 are shown below as they relate to
DL260 and DL06 CPUs.
Rung 5 writes the values from V2000 to V2023 to the drive parameters P 9.11 to
P 9.30. In the MWX box, the Start Slave Memory Address value is 42316. 42316 is a
MODBUS decimal number. To convert 42316 decimal to hex, you first subtract 40001,
and then convert the remainder to hex (90B). 90B is the address for parameter P 9.11.
If you only want to control the start/stop and speed reference of the drive, simply change
the number of elements to K2 and the slave memory address to 42331. Then V2000
would be your speed reference location and V2001 would be your start/stop location.
SP116 C100
5 MWX
Port Number: K2
Slave Address: K1
Function Code: 16 - Preset Multiple Registers
Start Slave Memory Address: 42316
Start Master Memory Address: V2000
Number of Elements: K20
Modbus Data type: 584/984 Mode
Exception Response Buffer: V5000
C100
( SET )
Rung 6 is used to read the status of the GS2 AC drive. These instructions read the
values from the GS2 status addresses, 2100 to 2105, and places the values into
the PLC memory addresses, V3000 to V3005.
The Start Slave Memory Address in the MRX box is 48449. 48449 is a MODBUS
decimal number. To convert 48449 decimal to hex, you first subtract 40001, and then
convert the remainder to hex (2100). 2100 is the address for the GS2 Status Monitor.
SP116 C100
6 MRX
Port Number: K2
Slave Address: K1
Function Code: 03 - Read Holding Registers
Start Slave Memory Address: 48449
Start Master Memory Address: V3000
Number of Elements: K6
Modbus Data type: 584/984 Mode
Exception Response Buffer: V5005
C100
(Cont. next page) ( RST )


Rung 7 is used to set bit C55 if the AC drive has an error. Rung 8 will reset bit C55.
Error code word 2100

in the drive Drive error
V3000 C55
K1
7 욷 ( SET )
Clear errors Drive error
X5 C55
8 ( RST )
Rung 9 is used to set bit C51 if the AC drive has a specific error. In this example
C51 will be set if the AC drive has an overcurrent error. Rung 10 will reset bit C51.
Error code word 2100
in the drive Overcurrent
V3000 C51
K1
9 = ( SET )
Clear errors Overcurrent
X5 C51
10 ( RST )
Rung 11 loads a value of 1 into drive parameter P 9.27. This is the signal to run.
V2020 is the 17th V-memory register in the block of 20 that is being written to in
the WX instruction in Rung 5.
X0 LD
11 K1
OUT
V2020
Rung 12 loads a value of 0 into drive parameter P 9.27. This is the signal to stop.
V2020 is the 17th V-memory register in the block of 20 that is being written to in
the WX instruction in Rung 5.
X0 LD
12 K0
OUT
V2020
(Cont. next page)


Rung 13 loads a decimal value of 150 into drive parameter P 9.26. The BIN
instruction converts BCD/HEX to decimal. This tells the drive to run at 15.0Hz.
X1 LD
13 K150
BIN
OUT
V2017
X2 LD
14 K300
BIN
OUT
V2017
X3 LD
15 K450
BIN
OUT
V2017
(Cont. next page)


X4 LD
16 K600
BIN
OUT
V2017
Rung 17 sets the motion of the drive to forward by loading a value of 0 into
parameter P 9.28. V2021 is the 18th V-memory register in the block of 20 that is
being written to in the WX instruction in Rung 5.
X6 LD
17 K0
OUT
V2021
Rung 18 sets the motion of the drive to reverse by loading a value of 1 into parameter
P 9.28. V2021 is the 18th V-memory register in the block of 20 that is being
written to in the WX instruction in Rung 5.
X7 LD
18 K1
OUT
V2021
19 ( END )
20 ( NOP )

Communicating with Third-party Devices

First you must decide what type of interface will work best for your application. The
GS2 RJ-11 Serial Comm Port can accomidate an RS232C or an RS 485 connection.
RS-232C
An RS-232C connection is somewhat limited. The maximum network cable length for
an RS-232C connection is 15 meters (50 feet). In addtion, using the RS-232C interface
will allow you to connect only one AC drive to one MODBUS device. For and RS-
232C connection, set the GS2 DIP switches SW2 and SW3 to RS232.

RS-232C Interface Switches SW2 and SW3
3: RXD
6 1 an RS-232C connection.
4: TXD SW3 SW2
5: +5V RS232
RS-485
An RS-485 network cable can span up to 1000 meters (4000 feet). For an RS-485
connection, set the GS2 DIP switches SW2 and SW3 to RS485.

RS-485 Interface Switches SW2 and SW3
3: SG-
6 1 an RS-485 connection.
4: SG+ SW3 SW2
5: +5V RS232
The GS2 Series AC drive communication address is specified by P 9.00. The third
party device then controls each AC drive according to its communication address.
The GS2 Series AC drive can be setup to communicate on standard MODBUS
networks using the following transmission modes: ASCII or RTU. Using the
Communication Protocol parameter (P 9.02), you can select the desired mode,
data bits, parity, and stop bits. The mode and serial parameters must be the same
for all devices on a MODBUS network.

Data Format
ASCII Mode: 10-bit character frame (For 7-bit character):
P 9.02 = 00 (7 data bits, no parity, 2 stop bits)
Start 0 1 2 3 4 5 6 Stop Stop

bit bit bit
7-bit character
10-bit character frame
P 9.02 = 01 (7 data bits, even parity, 1 stop bit)
Start 0 1 2 3 4 5 6 Even Stop

bit parity bit
7-bit character
P 9.02 = 02 (7 data bits, odd parity, 1 stop bit)
Start 0 1 2 3 4 5 6 Odd Stop

bit parity bit
7-bit character
RTU Mode: 11-bit character frame (For 8-bit character):

P 9.02 = 03 (8 data bits, no parity, 2 stop bit)
Start 0 1 2 3 4 5 6 7 Stop Stop

bit bit bit
8-bit character
P 9.02 = 04 (8 data bits, even parity, 1 stop bit)
Start 0 1 2 3 4 5 6 7 Eve Stop

bit parity bit
8-bit character

P 9.02 = 05 (8 data bits, odd parity, 1 stop bit)
Start 0 1 2 3 4 5 6 7 Odd Stop

bit parity bit
8-bit character
Communication Protocol
ASCII Mode:
STX Start Character: (3AH)
ADR 1
ADR 0
Communication Address: 8-bit address consists of 2 ASCII codes
CMD 1
CMD 0
DATA (n-1)
Contents of data: n x 8-bit data consists of 2n ASCII codes. n[]25
.......
maximum of 50 ASCII codes
DATA 0
LRC CHK 1
LRC check sum: 8-bit check sum consists of 2 ASCII codes
LRC CHK 0
END 1
END characters: END 1=CR (0DH), END 0 =LF (0AH)
END-0
RTU Mode:
START A silent interval of more than 10 ms
ADR
Communication Address: 8-bit address
CMD
DATA (n-1)
....... Contents of data: n x 8-bit data,n<=25
DATA 0
CRC CHK Low
CRC check sum: 16-bit check sum consists of 2 8-bit characters
CRC CHK High
END A silent interval of more than 10 ms
ADR (Communication Address)

Valid communication addresses are in the range of 0 to 254. Communication
address equals to 0 means broadcast to all AC drives (AMD), in this case, the
AMD will not reply any message to the master device.
For example, communication to AMD with address 16 decimal:
ASCII mode: (ADR 1, ADR 0)='1','0' => '1'=31H, '0'=30H
RTU mode: (ADR)=10H

CMD (Command code) and DATA (data characters)

The format of data characters depends on the command code. The available
command codes are described as followed: Command code: 03H, read N words.
The maximum value of N is 12. For example, reading continuous 2 words from
starting address 2102H of AMD with address 01H.
ASCII mode:
Command Message Response Message
STX ':' STX ':'
ADR 1 '0' ADR 1 '0'
ADR 0 '1' ADR 0 '1'
CMD 1 '0' CMD 1 '0'
CMD 0 '3' CMD 0 '3'
'2' Number of data '0'
Starting data '1' (Count by byte) '4'
address '0' '1'
'2' Content of starting '7'
data address
'0' 2102H '7'
Number of data '0' '0'
(Count by word) '0' '0'
'2' Content data '0'
LRC CHK 1 'D' address 2103H '0'
LRC CHK 0 '7' '0'
END 1 CR LRC CHK 1 '7'
END 0 LF LRC CHK 0 '1'
END 1 CR
END 0 LF
RTU mode:
ADR 01H ADR 01H
CMD 03H CMD 03H
Starting data 21H Number of data 04H
address 02H (Count by byte)
Number of data 00H Content of data 17H

(Count by word) 02H address 2102H 70H
CRC CHK Low 6FH Content of data 00H
CRC CHK High F7H address 2103H 02H
CRC CHK Low FEH
CRC CHK High 5CH

Command code: 06H, write 1 word

For example, writing 6000(1770H) to address 0100H of AMD with address 01H.
ASCII mode:
STX ':' STX ':'
ADR 1 '0' ADR 1 '0'

ADR 0 '1' ADR 0 '1'
CMD 1 '0' CMD 1 '0'

CMD 0 '6' CMD 0 '6'
'0' '0'
'1' '1'
Data Address
'0' '0'
'0' '0'
Data Address
'1' '1'
'7' '7'
Data Content
'7' '7'
'0' '0'
LRC CHK 1 '7' LRC CHK 1 '7'

LRC CHK 0 '1' LRC CHK 0 '1'
END 1 CR END 1 CR
END 0 LF END 0 LF
RTU mode:
This is an example of using function code 16 for writing to multiple registers.

ADR 01H ADR 01H
CMD 10H CMD 10H
Starting data 20H Starting data 20H
address 00H address 00H
Number of data 04H Number of data 00H
(Count by byte) (Count by word) 02H
Content of data 00H CRC CHK Low 4AH
address 2000H 02H CRC CHK High 08H
Content of data 02H
address 2001H 58H
CRC CHK Low CBH
CRC CHK High 34H

CHK (check sum)

ASCII Mode:
LRC (Longitudinal Redundancy Check) is calculated by summing up, module 256,
the values of the bytes from ADR1 to last data character then calculating the
hexadecimal representation of the 2's-complement negation of the sum.
For example, reading 1 word from address 0401H of the AC drive with address 01H.
Command Message
STX ':'
ADR 1 '0'
ADR 0 '1'
CMD 1 '0'
CMD 0 '3'
'0'
Starting data '4'
address '0'
'1'
'0'
01H+03H+04H+01H+00H+01H=0AH,
Number of data '0'
the 2's complement negation of 0AH is F6H.
(Count by word) '0'
'1'
LRC CHK 1 'F'
LRC CHK 0 '6'
END 1 CR
END 0 LF
RTU Mode:
Response Message
ADR 01H
CMD 03H
Starting data 21H
address 02H
Number of data 00H
(Count by word) 02H
CRC CHK Low 6FH
CRC CHK High F7H

CRC (Cyclical Redundancy Check) is calculated by the following steps:

Step 1: Load a 16-bit register (called CRC register) with FFFFH.
Step 2: Exclusive OR the first 8-bit byte of the command message with the low order
byte of the 16-bit CRC register, putting the result in the CRC register.
Step 3: Shift the CRC register one bit to the right with MSB zero filling. Extract and
examine the LSB.
Step 4: If the LSB of CRC register is 0, repeat step 3, else Exclusive or the CRC
register with the polynomial value A001H.
Step 5: Repeat step 3 and 4 until eight shifts have been performed. When this is
done, a complete 8-bit byte will have been processed.
Step 6: Repeat steps 2 to 5 for the next 8-bit byte of the command message.
Continue doing this until all bytes have been processed. The final contents of the
CRC register are the CRC value.
Note: When transmitting the CRC value in the message, the upper and lower bytes of
the CRC value must be swapped, i.e. the lower order byte will be transmitted first.
The following is an example of CRC generation using C language. The function

takes two arguments:
Unsigned char* data 씯 a pointer to the message buffer
Unsigned char length 씯 the quantity of bytes in the message buffer
The function returns the CRC value as a type of unsigned integer.
Unsigned int crc_chk(unsigned char* data, unsigned char length){
int j;
unsigned int reg_crc=0xFFFF;
while(length--){
reg_crc ^= *data++;
for(j=0;j<8;j++){
if(reg_crc & 0x01){ /* LSB(b0)=1 */
reg_crc=(reg_crc>>1) ^ 0xA001;
}else{
reg_crc=reg_crc >>1;
}
}
}
return reg_crc;
}

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GS2 MODBUS CHAPTER

Communication Parameters Summary

00: MODBUS ASCII mode

00: Display fault and continue operating

P 9.05 Time Out Duration 0.1 to 60.0 seconds 0.5

쏆 P 9.11 Block Transfer Parameter 1 P 0.00 to P 8.01 P 9.99

5–2 GS2 Series AC Drive User Manual

Communication Parameters Summary (cont.)

GS2 Series AC Drive User Manual 5–3

GS2 Status Addresses

Status Addresses (Read Only)

Frequency Command F (XXX.X) Memory Address 2102H

Output Frequency H (XXX.X) Memory Address 2103H

Output Current A (XXX.X) Memory Address 2104H

DC-BUS Voltage d (XXX.X) Memory Address 2105H

Output Voltage U (XXX.X) Memory Address 2106H

Power Factor Angle Memory Address 210AH

Software Version Memory Address 2110H

5–4 GS2 Series AC Drive User Manual

Communicating with DirectLOGIC PLCs

Step 1: Choose the Appropriate CPU.

Step 2: Make the Connections

DL250: RS-232C Connection Wiring 2 TXD 3 RXD

GS2 Series AC Drive User Manual 5–5

DL05: RS-485 Connection Wiring GS2

DL250: RS-485 Connection Wiring GS2

DL350/DL450 DL350/DL450: RS-485 Connection Wiring

5–6 GS2 Series AC Drive User Manual

Step 3: Set AC Drive Parameters

Step 4: Configure the DirectLOGIC CPUs

GS2 Series AC Drive User Manual 5–7

DirectLOGIC MODBUS Port Configuration

• In the Timeout list box, select “800 mS”.

• The Baud Rate should be set at “9600”.

5–8 GS2 Series AC Drive User Manual

DirectLOGIC MODBUS Ladder Programming

In many drive applications, electromagnetic interference can at times cause

Comm transaction count

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GS2 Series AC Drive User Manual 5–9

DirectLOGIC MODBUS Ladder Programming (cont.)

Comm error count Drive comm error

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5–10 GS2 Series AC Drive User Manual

DirectLOGIC MODBUS Ladder Programming (cont.)

GS2 Series AC Drive User Manual 5–11

Alternate MODBUS Ladder Programming

5–12 GS2 Series AC Drive User Manual

DirectLOGIC MODBUS Ladder Programming (cont.)

Error code word 2100

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GS2 Series AC Drive User Manual 5–13

DirectLOGIC MODBUS Ladder Programming (cont.)

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5–14 GS2 Series AC Drive User Manual

DirectLOGIC MODBUS Ladder Programming (cont.)

GS2 Series AC Drive User Manual 5–15

Communicating with Third-party Devices

RJ-11 Serial Comm Port RS485