Super Systems AC20 RS485 User Manual

TITLE: MODBUS/J-BUS Protocol for SSi’s - AC20 ENG. 824E

Rev. Date Description Written Verified Approved Prot.

0 04/30/98 First Issue
1 12/9/98

See shaded areas

98/144

MODBUS/J-BUS PROTOCOL FOR

SSi’s - AC20

All the information contained within this document are Company’s

confidential. Their content therefore cannot be divulged and/or

reproduced.

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TITLE: MODBUS/J-BUS Protocol for SSi’s- AC20 ENG. 824E REV. 1

MODBUS/J-BUS PROTOCOL FOR

SSi’s - AC20

This document complies with ENG824E, Rev. 1 dated December 9, 1998.

The first page of this document is for R&D use only.

Headquarters: Factory:
Super Systems Inc
4250 Creek Road
Cincinnati, OH 45241
513-772-0060
www.supersystems.com

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TITLE: MODBUS/J-BUS Protocol for SSi’s- AC20 ENG. 824E REV. 1

INDEX

Introduction Page 4
Function code 1 and 2: Bits reading Page 6
Function code 3 and 4: Words reading Page 7
Function code 5: Single bit writing Page 8
Function code 6: Single word writing Page 9
Function code 15: Multiple bits writing Page 10
Function code 16: Multiple words writing Page 11
Notes Page 12
Error reply Page 15
Words for device in control mode - Parameters Page 18
Words for device in control mode - Non parameters Page 26
Bits for device in control mode Page 31
Words for device in configuration mode - Parameters Page 37
Words for device in configuration mode - Non parameters Page 45
Words for device in security code mode Page 46
Index, divided in families and groups, of Modbus words Page 48
Index of Modbus bits Page 53
Index, in ascending order, of Modbus words Page 54
Index, in ascending order, of Modbus bits Page 58
Additional and specialized technical notes Page 59

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TITLE: MODBUS/J-BUS Protocol for SSi’s- AC20 ENG. 824E REV. 1

INTRODUCTION

This half duplex protocol accepts one master and one or more slaves.
The physical interface should be of the RS-485 type.

A single multidrop link can take up to 128 devices having the same “High input impedance”
as the transceiver used..

The computer should be programmed to serve as a master controlling which slave has
access to the link. All other slaves are in waiting state. Each slave has a unique address
ranging from 1 to 255.
Address “0” is a broadcast one. When the master sends a message with address 0, all
slaves receive it and no one replies.

TRANSMISSION FORMAT

The protocol uses the RTU (Remote terminal unit) mode of transmission.
RTU is a binary method with byte format composed as follows:

1 start bit, 8 data bit, 1 parity bit (optional), 1 stop bit.
The communication speed is selectable among 600, 1200, 2400, 4800, 9600 and 19200

baud.

COMMUNICATION PROCEDURE

The communication can be initiated only by the master unit; the slave units can transmit
only after a query has been received from the master.
The general format for the transmission from master to slave is the following:

RANGE BYTE

Slave address 1
Function code 1
Data n
Error check (CRC-16) (low byte) 1
Error check (CRC-16) (high byte) 1

The slave detects the start of a query frame when the delay time between two characters
is greater than 3.5 T.U. (Time Unit = Time necessary to transmit one character).

ERROR CHECK(CRC-16 Cyclical Redundancy Check)
The CRC-16 value is calculated by the transmitting device. This value is appended to the

message. The receiving device recalculates a CRC-16 and compares the calculated value
to the received value. The two values must be equal.

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TITLE: MODBUS/J-BUS Protocol for SSi’s- AC20 ENG. 824E REV. 1

The CRC-16 is started by first pre-loading a 16-bit register to all 1's. Then a process begins
of applying successive the bytes of the message to the current contents of the register.
Only the eight bits of data in each character are used for generating the CRC-16. Start and
stop bits, and the parity bit if one is used, do not apply to the CRC-16.
During generation of the CRC-16, each byte is exclusive ORed with the register contents.
Then the result is shifted to the right , with a zero filled into the most significant bit (MSB)
position. If the LSB was a 1, the register is then exclusive ORed with a preset, fixed value.
If the LSB was a 0, no exclusive OR takes place.
This process is repeated until eight shifts have been performed. After the last shift, the
next byte is exclusive ORed with the register's current value, and the process repeats for
eight more shifts as described above. The final contents of the register, after all the
characters of the message have been applied, is the CRC-16 value.

A procedure for generating a CRC-16 is:

1) Load a 16-bit register (CRC-16 register) with FFFFh (all 1's).

2) Exclusive OR the first byte of the message with the low byte of the CRC-16

register. Put the result in the CRC-16 register.

3) Shift the CRC-16 register one bit to the right (toward the LSB), zero-filling the

MSB. Extract and examine the LSB.

4) (If the LSB was 0): Repeat Step 3 (another shift).
(If the LSB was 1): Exclusive OR the CRC-16 register with the polynomial
value A001h (1010 0000 0000 0001b).

5) Repeat Steps 3 and 4 until 8 shifts have been performed. When this is done,

a complete byte will have been processed.

6) Repeat Steps 2 through 5 for the next byte of the message.
Continue doing this until all bytes have been processed.

7) The final contents of the CRC-16 register is the CRC-16 value.

When the CRC-16 (16 bytes) is transmitted in the message, the low byte
will be transmitted first, followed by the high byte

N.B. : the numerical value present in this text are expressed as:

binary value if they are followed by b
decimal value if they are not followed by any letter
hexadecimal value if they are followed by h

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Function code 1 and 2: Bits reading

These function codes are used by the master unit to request the value of a consecutive
group of bits (max 24) which are representing the status of the slave unit.

Request from master to slave Reply from slave to master

Range Byte Range Byte
Slave address (1-255) 1 Slave address (1-255) 1
Function code (01-02) 1 Function code (01-02) 1
Bit starting address (high byte) 1 Byte count (n) 1
Bit starting address (low byte) 1 Data n
Number of bits (high byte) 1 Error check (CRC-16) (low byte) 1
Number of bits (low byte) 1 Error check (CRC-16) (high byte) 1
Error check (CRC-16) (low byte) 1
Error check (CRC-16) (high byte) 1

The “Data” field indicates the bits requested: the bit with lower address is in the bit 0 of the
first byte, the next is in the bit 1, and so on.
The eventual don’t care bits necessary to complete the last byte are equal to 0.

Example:
Ask to slave at address 100 (64h) the status of 14 (Eh) bits starting from bit 201 (C9h).

Request from master to slave Reply from slave to master

Range Byte Range Byte
Slave address 64h Slave address 64h
Function code 01h Function code 01h
Bit starting address (high byte) 00h Byte count 02h
Bit starting address (low byte) C9h Data A7h
Number of bits (high byte) 00h Data 04h
Number of bits (low byte) 0Eh Error check (CRC-16) (low byte) 8Eh
Error check (CRC-16) (low byte) 64h Error check (CRC-16) (high byte) 07h
Error check (CRC-16) (high byte) 05h

The 2 bytes in “Data“ field (A7h=10100111b, 04h=00000100b) mean:
bit 201 status = 1 bit 209 status = 0

bit 202 status = 1 bit 210 status = 0
bit 203 status = 1 bit 211 status = 1
bit 204 status = 0 bit 212 status = 0
bit 205 status = 0 bit 213 status = 0
bit 206 status = 1 bit 214 status = 0
bit 207 status = 0 Don’t care = 0
bit 208 status = 1 Don’t care = 0

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Function code 3 and 4: Words reading

These function codes are used by the master unit to read a consecutive group of words
(16 bit) which contain the value of the variable of the slave unit.
The master can require a maximum of 20 words at a time.

Request from master to slave Reply from slave to master

Range Byte Range Byte
Slave address (1-255) 1 Slave address (1-255) 1
Function code (03-04) 1 Function code (03-04) 1
Word starting address (high

1 Byte count (n) 1
byte)
Word starting address (low byte) 1 Data n
Number of word (high byte) 1 Error check (CRC-16) (low byte) 1
Number of word (low byte) 1 Error check (CRC-16) (high byte) 1
Error check (CRC-16) (low byte) 1
Error check (CRC-16) (high byte) 1

The “Data” field contains the requested words in the following format: high bytes of the first
word, low byte of the first word, high byte of the second word, and so on.
The “data” field contains 8000h for not implemented addresses or for information not
relevant in the actual device configuration.

Example:
Ask to slave at address 29 (1Dh) the value of 3 words (3h) starting from word 178 (B2h)

Request from master to slave Reply from slave to master

Range Byte Range Byte
Slave address 1Dh Slave address 1Dh
Function code 03h Function code 03h
Word starting address (high byte) 00h Byte count 06h
Word starting address (low byte) B2h Data FFh
Number of words (high byte) 00h Data 9Ch
Number of words (low byte) 03h Data 80h
Error check (CRC-16) (low byte) A7h Data 00h
Error check (CRC-16) (high byte) B0h Data 05h

Data 5Ah
Error check (CRC-16) (low byte) D7h
Error check (CRC-16) (high byte) 0Dh

The 6 bytes in “Data” field (FFh, 9Ch, 80h, 00h, 05h, 5Ah) are 3 words whose meaning is:
word 178 value = -100 (FF9Ch)

word 179 value = not implemented or not relevant (8000h)
word 180 value = 1370 (55Ah)

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Function code 5: Single bit writing

By using this command, the master unit can change the state of one bit of the slave unit.

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address (0*-255) 1 Slave address (1-255) 1
Function code (05) 1 Function code (05) 1
Bit address (high byte) 1 Bit address (high byte) 1
Bit address (low byte) 1 Bit address (low byte) 1
Data 2 Data 2
Error check (CRC-16) (low byte) 1 Error check (CRC-16) (low byte) 1
Error check (CRC-16) (high byte) 1 Error check (CRC-16) (high byte) 1

* To use the address 0, see note 1 at page 12: “Broadcast address”.
“Data” field = 0h to reset the bit

= FF00h to set the bit

Example:
Set bit 219 (DBh) of slave at address 35 (23h)

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address 23h Slave address 23h
Function code 05h Function code 05h
Bit address (high byte) 00h Bit address (high byte) 00h
Bit address (low byte) DBh Bit address (low byte) DBh
Data FFh Data FFh
Data 00h Data 00h
Error check (CRC-16) (low byte) FAh Error check (CRC-16) (low byte) FAh
Error check (CRC-16) (high byte) 83h Error check (CRC-16) (high byte) 83h

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Function code 6: Single word writing

By using this command, the master unit can change the value of one word (16 bit) of the
slave unit.

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address (0*-255) 1 Slave address (1-255) 1
Function code (06) 1 Function code (06) 1
Word address (high byte) 1 Word address (high byte) 1
Word address (low byte) 1 Word address (low byte) n
Data 2 Data 2
Error check (CRC-16) (low byte) 1 Error check (CRC-16) (low byte) 1
Error check (CRC-16) (high byte) 1 Error check (CRC-16) (high byte) 1

* To use the address 0, see note 1 at page 12: “Broadcast address”.
The 8000h value, present in the “data” field, should be considered as a don’t care value,

that is, the value present in the device at this address will not be modified.

Example:
Set word 2006 (7D6h) of slave at address 5 (5h) with value 1250 (4E2h)

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address 05h Slave address 05h
Function code 06h Function code 06h
Word address (high byte) 07h Word address (high byte) 07h
Word address (low byte) D6h Word address (low byte) D6h
Data 04h Data 04h
Data E2h Data E2h
Error check (CRC-16) (low byte) EAh Error check(CRC-16) (low byte) EAh
Error check (CRC-16) (high byte) 4Bh Error check (CRC-16) (high byte) 4Bh

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Function code 15: Multiple bits writing

This function code is used by master unit to set/reset a consecutive group of bits (max 24).

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address (0*-255) 1 Slave address (1-255) 1
Function code (15) 1 Function code (15) 1
Bit starting address (high byte) 1 Bit starting address (high byte) 1
Bit starting address (low byte) 1 Bit starting address (low byte) 1
Number of bits (high byte) 1 Number of bits (high byte) 1
Number of bits (low byte) 1 Number of bits (low byte) 1
Byte counter (n) 1 Error check (CRC-16) (low byte) 1
Data n Error check (CRC-16) (high byte) 1
Error check (CRC-16) (low byte) 1
Error check (CRC-16) (high byte) 1

* To use the address 0, see note 1 at page 12: “Broadcast address”.
The desired status of each bit is packed in the DATA field (1 = ON, 0 = OFF).
The status imposed for read only bits will be ignored.
The command will be processed starting from the first bit and it will be executed or not
executed depending on the actual device status.
At the first error found, the command will be aborted and the slave will answer with an
error.

Example:
Send to slave, at address 2 (2h), the following set of 9 bits:
bit 224 status = 0 (bit 0) bit 232 status = 1 (bit 0)
bit 225 status = 1 (bit 1) Don’t care = 0 (bit 1)
bit 226 status = 1 (bit 2) Don’t care = 0 (bit 2)
bit 227 status = 0 (bit 3) Don’t care = 0 (bit 3)
bit 228 status = 1 (bit 4) Don’t care = 0 (bit 4)
bit 229 status = 0 (bit 5) Don’t care = 0 (bit 5)
bit 230 status = 1 (bit 6) Don’t care = 0 (bit 6)
bit 231 status = 1 (bit 7) Don’t care = 0 (bit 7)

NOTE: 2 bytes with 9 bits and 7 don’t care bits must be sent

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address 02h Slave address 02h
Function code 0Fh Function code 0Fh
Bit starting address (high byte) 00h Bit starting address (high byte) 00h
Bit starting address (low byte) E0h Bit starting address (low byte) E0h
Number of bits (high byte) 00h Number of bits (high byte) 00h
Number of bits (low byte) 09h Number of bits (low byte) 09h
Byte counter 02h Error check (CRC-16) (low byte) 94h
Data D6h Error check (CRC-16) (high byte) 08h
Data 01h
Error check (CRC-16) (low byte) 78h
Error check (CRC-16) (high byte) 4Ch

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Function code 16: Multiple words writing

This function code is used by the master unit to write a consecutive group of words .
The master unit can change a maximum of 20 words at a time.

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address (0*-255) 1 Slave address (1-255) 1
Function code (16) 1 Function code (16) 1
Word starting address (high

1 Word starting address (high byte) 1
byte)
Word starting address (low byte) 1 Word starting address (low byte) 1
Number of words (high byte) 1 Number of words (high byte) 1
Number of words (low byte) 1 Number of words (low byte) 1
Byte counter (n) 1 Error check (CRC-16) (low byte) 1
Data n Error check (CRC-16) (high byte) 1
Error check (CRC-16) (low byte) 1
Error check (CRC-16) (high byte) 1

* To use the address 0, see note 1 at page 12: “Broadcast address”.
The data imposed for read only words will be ignored.
The command will be processed starting from the first word and it will be executed or not
executed depending on the actual device status.
At the first error found, the command will be aborted and the slave will answer with an
error.
The 8000h value, present in the “data” field, should be considered as a don’t care value,
this is, the value present in the device at this address will not be modified.

Example:
Set words 139 (8Bh), 140 (8Ch), 141 (8Dh) of slave at address 10 (Ah) with 300 (12Ch),
don’t care (8000h) and 700 (2BCh) values.

Command from master to slave Reply from slave to master

Range Byte Range Byte
Slave address 0Ah Slave address 0Ah
Function code 10h Function code 10h
Word starting address(high byte) 00h Word starting address (high byte) 00h
Word starting address (low byte) 8Bh Word starting address (low byte) 8Bh
Number of words (high byte) 00h Number of words (high byte) 00h
Number of words (low byte) 03h Number of words (low byte) 03h
Byte counter 06h Error check (CRC-16) (low byte) F1h
Data 01h Error check (CRC-16) (high byte) 59h
Data 2Ch
Data 80h
Data 00h
Data 02h
Data BCh
Error check (CRC-16) (low byte) 33h
Error check (CRC-16) (high byte) 00h

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NOTES:

1. “Broadcast” address

When using the writing codes (5, 6, 15 and 16) the slave address 0 is permitted: in this

case all the slaves connected accept the command but do not give any reply.

2. Words format

Every time the information transfer is performed by using 2 bytes (1 word of 16 bits), the

first byte transmitted is the most significant one. For the negative numbers the “two
complement” format is used.

3. Reply time

The slave will start to send a reply from 2 ms to 250 ms after the end of the request
detected by counting the received bytes

4. Decimal digits

The decimal point that may be present in the value is ignored.
Example:

The value 204.6 is transmitted as 2046 (07FEh)
The value -12.50 is transmitted as -1250 (FB1Eh)

5. Local/remote status

At power up, the slave will be in local mode if it was in control mode at power off. In the
other cases, it will maintain the condition it was at the power off.

In order to enable a slave to be controlled from the master, it is necessary to set the
local/remote status bit (ModBus bit 218).

For a slave to remain in remote status, it is sufficient to detect line activity.
If there is no line activity for more than 3 sec. every slave will automatically return to

local mode.
Local mode: the communication between master and slave is limited to

transferring data from slave to master without possibility of modifying
any parameter from the master itself (with the exception of the
local/remote status bit). Therefore from the local keyboard,
parameters can be displayed and modified.

Remote mode: the instrument parameters can be modified by the master. Therefore,

from the local keyboard the parameters can be only displayed but not
modified.

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6. Control mode

“Control mode” indicates the normal functioning status of the device
(indicator/controller).

In control mode they are parameters (menu groups), variables and status.
The parameters (Menu groups) are represented by words only.
Bits and words represent the variables and the status.

Reading:
The parameters (menu groups) are available only if they are meaningful in the present
contest.
The variables and the status are available only if the device is in control mode and if
they are meaningful in the present contest

Writing:
All the addresses are available only if the device is in control mode, in remote mode, in
unlock condition (see note 9) and if they are meaningful in the present contest

7. Configuration mode

The configuration parameters (Menu conf.) are represented by words only.
They are available as read only if they are meaningful in the present contest
They are available as writing only if the device is in configuration mode, and they are
meaningful in the present contest

At the end of the parameters programming of a configuration menu it is opportune to
send the “end of configuration menu” command (ModBus words 3000 ÷ 3005). The
congruence of the programmed data compared with the data of the other configuration
menus is checked. In case of non compatibility, the reply will include a 1xx error
message where xx represents the number of the menus whose closure has caused the
error.

The end of the group programming is anyway automatically sent if data of a different
menu are programmed or read and if the output of the configuration mode is imposed.

To modify the configuration parameters via serial link, it is necessary to set the slave in
remote (ModBus bit 218). Then, set the slave in configuration mode (send the safety
lock combination value for configuration mode to ModBus word 347 *).
The display will show:

SEr
COnF

To return in control mode condition, send 1 to Modbus word 3051. The slave will reset
and restart in control mode condition.

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8. Security code mode

The security code parameters are represented by words only.
They are always available as read.
They are available as writing only if the device is in security code mode.

To modify the security code parameters via serial link, it is necessary to set the slave in
remote (ModBus bit 218). Then, set the slave in security code mode (send the safety
lock combination value for configuration mode to ModBus word 348 *).
The display will show:

Scrt
COnF

To return in control mode condition, send 1 to ModBus word 3051. The slave will reset
and restart in control mode condition.

* If the value of safety lock combination for configuration mode is 0, all values will be

accepted. If the value is 1, no value will be accepted.

The safety lock combination is the value set at ModBus word 4000.

9. Software key for lock/unlock

Software keys can protect the modification of the parameters.
There is a key to protect the access to configuration mode and security code mode.
There is a second key to protect the modification of control mode parameters.
Once the control mode key is programmed, it is possible to decide which menus will be
protected and which menus will not be protected.

Keys management via serial link
Set the slave in remote (ModBus bit 218).

Set the slave in security code mode (send the present safety lock combination value for
configuration mode at ModBus word 348).
Set the new safety lock combination value for configuration mode at ModBus word

4000.
Set the new safety lock combination value for control mode at ModBus word 4001.

To protect control mode menus with the key, write 1 (key protected) in Modbus words
4002÷4011. Write 0 (free) if no key protection is needed.

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N.B.:

Safety lock combination = 0: No security code (all parameters can always be

modified)
If safety lock combination is for control mode, ModBus
word 4002÷4011 are forced to 0.

Safety lock combination = 1: No security code (all parameters cannot be modified).

If safety lock combination is for control mode, ModBus
word 4002÷4011 are forced to 1.

Safety lock combination=2÷250: Security code for parameter protection.

In order to remove the protection for the control mode
parameters, it is necessary to write the safety lock
combination value for control mode at ModBus word

349. It is sufficient to do this once only.
In order to protect the control mode parameters, it is
necessary to write a value different from the safety
lock combination value for control mode at ModBus
word 349.

In order to modify the configuration parameters, it is
necessary to set the configuration mode by writing the
safety lock combination value for configuration mode
at ModBus word 347.
In order to modify the security code parameters, it is
necessary to set security code mode by writing the
safety lock combination value for configuration mode
at ModBus word 348.

ERROR REPLY

If the “error check” is wrong or the function code is not implemented or a buffer over flows
has been received, the slave does not send any reply to the master.
If other errors are detected in the request or command frame, or the slave cannot reply
with the requested values or it cannot accept the requested sets because it is in error
condition, the slave replies by forcing at “1” the bit 7 of the “Function code” byte followed
by an error code.

Error reply (from slave to master)

RANGE BYTE

Slave address 1
Function code (+80h) 1
Error code 1
Error check (CRC-16) 2

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List of error codes

ERROR Nr. DESCRIPTION

2 Illegal data address
3 Illegal data value
9 Illegal number of data required

10 The bit or word indicated cannot be modified
50 The procedure cannot be initiated because another procedure is in pro-

gress

51 The procedure cannot be initiated because the first part of SMART

algorithm (TUNE) is in progress

52 The procedure cannot be initiated because it is not elapsed 5 minutes

from power on or from end of another procedure

53 The procedure cannot be initiated because the probe temperature is less

than 1000°F/538°

54 The procedure cannot be initiated because the probe output is less than

1000 mV

55 The procedure cannot be initiated because the probe output is unstable

(drift > 10 mV/minute)

101 Error on configuration group 1
102 Error on configuration group 2
103 Error on configuration group 3
104 Error on configuration group 4
105 Error on configuration group 5
106 Error on configuration group 6

151 Error on control mode group 1
152 Error on control mode group 2
153 Error on control mode group 3
154 Error on control mode group 4
155 Error on control mode group 5
156 Error on control mode group 6
157 Error on control mode group 7
158 Error on control mode group 8
159 Error on control mode group 9
160 Error on control mode group Hidden

200
201
202

Error on main probe input calibration (0÷1.5 V)
Error on main probe input calibration (1÷1.3 V)

Error on TC input calibration (0÷60 mV)
203 Error on CJ calibration
204
205
206
207
208

Error on auxiliary input current (0÷20 mA) calibration

Error on auxiliary input voltage (0÷5 V) calibration

Error on auxiliary input voltage (0÷10 V) calibration

Error on Out 6 (0÷20 mA output) calibration

Error on Out 7 (0÷20 mA output) calibration

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On configuration error condition (101÷106), the device will replace the error message with
the requested value in the following cases:

• request of configuration mode menu addresses

• request of control mode menu addresses

• request of security code mode addresses

It will accept the following sets:

• set in remote (ModBus bit 218)

• set in configuration mode (ModBus word 347)

• set in security code mode (ModBus word 348)

• set of all of configuration addresses

• set of all of security code mode addresses

On control mode error condition (151÷160), the device will replace the error message with
the requested value in the following cases:

• request of configuration mode menu addresses

• request of control mode menu addresses

• request of security code mode addresses

It will accept the following sets:

• set in remote (ModBus bit 218)

• set in configuration mode (ModBus word 347)

• set in security code mode (ModBus word 348)

• set of all of configuration addresses

• set of all of control mode menu addresses

• load of control mode default parameters (ModBus bits 223÷232)

• set of all of security code mode addresses

On calibration error condition (200÷208), the device will replace the error message with the
requested value in the following cases:

• request of configuration mode menu addresses

• request of control mode menu addresses

• request of security code mode menu addresses

It will accept the following sets:

• set in remote (ModBus bit 218)

• set in configuration mode (ModBus word 347)

• set in security code mode (ModBus word 348)

• set of all of configuration mode addresses

• set of all of security code mode addresses

If a configuration or control mode or calibration error occurs at start up and no action is
taken, the device will reset after a 30 second time-out.
In configuration mode, the time-out will be disable.

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WORDS FOR DEVICE IN CONTROL MODE - PARAMETERS

“St.Pn” - Menu group 1 - SET POINT VALUES

ADDRESS

(decimal) DEC. Display R

DESCRIPTION FIGU-

JBus Mod

Bus

139 138 Main set point
140 139 Auxiliary set point 2
141 140 Auxiliary set point 3
142 141 Auxiliary set point 4

RES

See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300

MNEM
CODE

E
A
D

(“SP”) x x
(“SP2”) x x
(“SP3”) x x
(“SP4”) x x

143 142 Carbon monoxide factor 0 (“COF”) x x
144 143 Hydrogen factor 0 (“H2F”) x x

“Alrñ” - Menu group 3 - ALARM THRESHOLD AND HYSTERESIS VALUE

ADDRESS

(decimal) DEC. Display R

DESCRIPTION FIGU-

JBus Mod

Bus

178 177 Alarm 1 threshold
179 178 Alarm 2 threshold
180 179 Alarm 3 threshold
182 181 Band alarm 1 threshold low
183 182 Band alarm 1 threshold high
184 183 Band alarm 2 threshold low
185 184 Band alarm 2 threshold high
186 185 Band alarm 3 threshold low
187 186 Band alarm 3 threshold high
192 191 Alarm 1 hysteresis
193 192 Alarm 2 hysteresis
194 193 Alarm 3 hysteresis

RES

See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300
See Mbus
Word 300

MNEM
CODE

E
A
D

(“AL1”) x x
(“AL2”) x x
(“AL3”) x x

(“bA1.L”) x x
(“bA1.h”) x x
(“bA2.L”) x x
(“bA2.h”) x x
(“bA3.L”) x x
(“bA3.h”) x x
(“HSA1”) x x
(“HSA2”) x x
(“HSA3”) x x

W

R

I
T
E

W

R

I
T
E

Page 19/59

TITLE: MODBUS/J-BUS Protocol for SSi’s- AC20 ENG. 824E REV. 1

WORDS FOR DEVICE IN CONTROL MODE - PARAMETERS

“Cntr” - Menu group 4 - CONTROL PARAMETERS

ADDRESS

(decimal) DEC. Display RWR

JBus Mod

Bus

DESCRIPTION FIGU-

RES

MNEM
CODE

E
A
D

149 148 Proportional band 1 (“Pb”) x x
150 149 Hysteresis for on/off control mode 1 (“HYS”) x x
151 150 Integral time (in seconds)

Note:

The value 7FFFh means that the integral
action is excluded

0 (“ti”) x x

152 151 Derivative time (in seconds) 0 (“td”) x x
153 152 Integral pre-load 1 (“IP”) x x
154 153 Relative secondary output gain 2 (“r.Gn”) x x
155 154 Dead band/overlap between main/secon-

0 (“OLAP”) x x

dary output

I
T
E