AZL...

Modbus

User Documentation

CC1A7550en
Building Technologies
01.02.2007 HVAC Products
 Supplementary documentation
User Documentation: Basic diagram for LMV5...
with 2 types of gases ........................................................................................... A7550.1
User Documentation: Basic diagram for LMV5...
with 2 types of liquefied fuels ............................................................................... A7550.3
Operating Instructions ACS450 PC Software for LMV5...........................................J7550
Setting Lists ..............................................................................................................I7550
Installation Basics LMV5… ...................................................................................J7550.1
Data Sheet LMV5.................................................................................................... N7550
Basic Documentation LMV5… ................................................................................ P7550
Range Overview LMV5… .......................................................................................Q7550
Operating Instructions AZL5… (U7550.2) for the heating engineer level ...74 319 0306 0
Operating Instructions AZL5… (U7550.3) for the enduser level .................74 319 0307 0

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 Contents
General ............................................................................................................................4
Master-slave principle ..............................................................................................4
Data transmission ............................................................................................................5
Transmission mode (RTU) .......................................................................................5
Structure of data blocks............................................................................................5
Checksum (CRC16) .................................................................................................5
Mapping words .........................................................................................................6
Mapping long values ................................................................................................6
Communication process ...........................................................................................6
Data query process ..................................................................................................7
Communication during the slave’s internal handling time ........................................7
Communication during the slave’s reply time ...........................................................7
Number of messages ...............................................................................................7
Reply time of AZL... to a message from the master .................................................7
Modbus functions .........................................................................................................8
Table of addresses ..........................................................................................................9
Legend to address table .........................................................................................14
Data types ..............................................................................................................14
Starting adaption via Modbus .................................................................................15
Updating rate of AZL... ..................................................................................................16
Error handling ................................................................................................................17
Selection menus in the AZL...........................................................................................18
Activation of Modbus operation ..............................................................................18
Slave address.........................................................................................................18
Transmission parameters .......................................................................................18
Timeout communication failure ..............................................................................18
Local «-» Remote mode .........................................................................................18
Remote mode .........................................................................................................18
AZL5... interface ............................................................................................................19
General...................................................................................................................19
Converter RS-232 – RS-485 .........................................................................................20
Technical requirements ..........................................................................................20
Commercially available converters.........................................................................20
Addendum 1: Overview of «Operating mode changeover of controller» .......................21
Notes on operating modes .........................................................................................22
Modbus downtime ..................................................................................................22
Changeover of operating mode via parameter 43 ..................................................22
Addendum 2: Default parameter settings ......................................................................23

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General
LMV5... LMV5... is a microprocessor-based burner management system with matching system
components for the control and supervision of forced draft burners of medium to high
capacity.

AZL... The burner management system is operated and programmed with the help of the
AZL5... display and operating unit or a PC tool.
The Modbus functionality of the AZL... display and operating unit serves for integrating
the LMV5... burner management system into a Modbus-based data network.
This makes possible the following applications:

- Visualization of plant operating states

- Plant control
- Logging

Master-slave principle

Communication between Modbus users takes place according to the master-slave

principle.

The AZL... always works as a slave.

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Data transmission

Transmission mode (RTU)

– The transmission mode used is RTU (Remote Terminal Unit)

– Data are transmitted in binary format (hexadecimal) with 8 bits
– The LSB (least significant bit) is transmitted first
– ASCII operating mode is not supported

Structure of data blocks

All data blocks use the same structure:

Data structure Slave address Function code Data field Checksum CRC16
1 byte 1 byte x byte 2 bytes

Every data block contains 4 fields:

Slave address Device address of a certain slave

Function code Function selection (reading / writing words)

Data field Contains the following information:

- Word address
- Number of words
- Word value

Checksum Identification of transmission errors

Checksum (CRC16)

The checksum (CRC16) is used to detect transmission errors. If, during evaluation, an
error is detected, the relevant device will not respond.

Calculation scheme CRC = 0xFFFF

CRC = CRC XOR ByteOfMessage
For (1 through 8)
CRC = SHR (CRC)
if (flag shifted at right = 1)
then else
CRC = CRC XOR
0xA001
while (not all ByteOfMessage handled)

& The low-byte of the checksum is transmitted first.

Example Data query: Reading 2 words from address 6 (CRC16 = 0x24A0)

0B 03 00 06 00 02 A0 24
CRC16

Reply: (CRC16 = 0x0561)

0B 03 04 00 00 42 C8 61 05
Word 1 Word 2 CRC16

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Mapping words

B0 B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 B12 B13 B14 B15

Byte High Byte Low

Transmission mode: The LSB (least significant bit) is transmitted first.

Mapping long values

Byte High Byte Low Byte High Byte Low

Word Low Word High

Communication process

Start and end of a data block are characterized by transmission pauses. The maximum
permissible time between 2 successive characters is 3.5 times the time required for the
transmission of once character.
The character transmission time is dependent on the Baud rate and the data format
used.

Having a data format of 8 data bits, no parity bit and one stop, the character transmis-
sion time is calculated as follows:

Character transmission time [ms] = 1000 * 9 bits / Baud rate

And with other data formats:

Character transmission time [ms] = 1000 * 10 bits / Baud rate

Process Data query from the master

Transmission time = n characters * 1000 * x bits / Baud rate

Marking for end of data query

3.5 characters * 1000 * x bits / Baud rate

Data query handling by the slave

Reply of slave
Transmission time = n characters * 1000 * x bits / Baud rate

Marking for end of reply

3.5 characters * 1000 * x bits / Baud rate

Example Marking for data query or end of reply with data format 10 / 9 bits

Waiting time = 3.5 characters * 1000 * x bits / Baud rate

Baud rate [Baud] Data format [bit] Waiting time [ms]

9600 10 3.125
9 2.813

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Data query process
Time diagram A data query is made according to the following time diagram:

Master Data query Data query

Slave Reply

7550z08e/0703 t0 t1 t0 t2
where:
t0 Marking for end = 3.5 characters (time is dependent on the Baud rate)
t1 This time is dependent on internal handling; the maximum handling time is de-
pendent on the data type (internal and external data) and on the number of data;
for more detailed information, see below!
t2 t2 ≥ 20 ms
This time is required by the device to switch from transmitting back to receiving;
this time must be observed by the master before a new data query is made; it
must always be observed, even if a new data query to some other device is made

Communication during the slave’s internal handling time

During the slave’s internal handling time, the master is not allowed to make any data
queries. The slave ignores data queries made during this period of time.

Communication during the slave’s reply time

During the slave’s reply time, the master is not allowed to make any data queries. Data
queries made during this period of time cause all data on the bus at this instant to be
deleted.

Number of messages
The number of addresses per message are limited:
• 20 addresses of the size of one word when reading
• 6 addresses of the size of one word when writing

Reply time of AZL... to a message from the master

1. Reading data from the LMV5... system:

1...3 addresses 25...75 ms

4...9 addresses 75...125 ms
10...15 addresses 125...175 ms
16...20 addresses 175...225 ms

Note These periods of time are defined from the complete writing of the message from the
master to sending the first byte by the AZL...

2. Writing data to the LMV5... system:

1 address 25...75 ms
2...3 addresses 75...125 ms
4...5 addresses 125...175 ms
6 addresses 175...225 ms

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Modbus functions
The following Modbus functions are supported:

Function number Function

03 / 04 Reading n words
06 Writing 1 word
16 Writing n words

For more information about the Modbus protocol, refer to www.modbus.org.

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 Table of addresses
Function Address Number Data designation Access Data Data type / Range Updating
of format coding rate
words
03/04 0 1 Phase R U16 0...255 Fast
03/04 1 1 Position of currently active fuel actuator R S16 PT_WINKEL -3... 93° Fast
03/04 2 1 Position of gas actuator R S16 PT_WINKEL -3...93° Fast
03/04 3 1 Position of oil actuator R S16 PT_WINKEL -3...93° Fast
03/04 4 1 Position of air actuator R S16 PT_WINKEL -3...93° Fast
03/04 5 1 Position of auxiliary actuator 1 R S16 PT_WINKEL -3...93° Fast
03/04 6 1 Position of auxiliary actuator 2 R S16 PT_WINKEL -3...93° Fast
03/04 7 1 Position of auxiliary actuator 3 R S16 PT_WINKEL -3...93° Fast
03/04 8 1 Manipulated variable for variable speed R S16 PT_PROZENTFU 0…100 % Fast
drive
03/04 9 1 Current type of fuel R U16 0= Gas 0...1 Fast
1= Oil
03/04 10 1 Current output R U16 PT_LEISTUNG 0…100 % Fast
03/04 11 1 Current setpoint / temperature / pressure R U16 PT_TEMP_ Medium
DRUCK
03/04 12 1 Actual value / temperature / pressure R U16 PT_TEMP_ 0…2000 °C Medium
Unit: See address 18 / 19 DRUCK 0…100 bar
03/04 13 1 Flame signal R U16 PT_PROZENT01 0…100 % Medium
03/04 14 1 Current fuel throughput R U16 0..65534 Fast
03/04 15 1 Current O2 value (LMV52...) R U16 PT_PROZENT01 0…100 % Fast
03/04 16 1 Volume unit of gas R U16 0= m³ 0…1 Slow
1= ft³
03/04 17 1 Volume unit of oil R U16 0= l 0…1 Slow
1= gal
03/04 18 1 Unit of temperature R U16 0= °C 0…1 Slow
1= °F
03/04 19 1 Unit of pressure R U16 0= bar 0…1 Slow
1= psi
03/04 20 1 Sensor selection R U16 0=Pt100 0…7 Slow
1=Pt1000
2=Ni1000
3=temp. sensor
4=press. sensor
5=Pt100Pt1000
6=Pt100Ni1000
7=no sensor
03/04 21 2 Startup counter total R S32 0…999999 Slow
03/04 23 2 Hours run counter R S32 0…999999 Slow
03/04 25 1 Current error: Error code R U16 0...0x FF Fast
03/04 26 1 Current error: Diagnostic code R U16 0…0x FF Fast
03/04 27 1 Current error: Error class R U16 0...5 Fast
03/04 28 1 Current error: Error phase R U16 0...255 Fast
03/04 29 1 Temperature limiter OFF threshold, in de- R U16 0…2000 °C Slow
grees Celsius / Fahrenheit 32…3632 °F
(in address 129: Temperature limiter switch-
ing differential ON)
03/04 30 1 Supply air temperature, in degrees Celsius / R U16 -100…+923 °C Slow
Fahrenheit (LMV52...) -148..+1693 °F
03/04 31 1 Flue gas temperature, in degrees Celsius / R U16 -100...+923 °C Slow
Fahrenheit (LMV52...) -148...+1693 °F
03/04 32 1 Combustion efficiency (LMV52...) R U16 PT_Prozent01 0...200 % Slow

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Function Address Number Data designation Ac- Data type / Range Updating
of cess coding rate
words
03/04 35 1 Inputs R U16 - Medium

Coding: 0 → inactive 1 → active

B15 B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0

B8 Safety loop B0 Controller ON/OFF

B9 B1 Fan contactor contact
B10 Pressure switch-min-gas B2 Fuel selection oil
B11 Pressure switch-max-gas B3 Fuel selection gas
B12 B4
B13 LP B5 Pressure switch-max-oil
B14 Start release oil B6 Pressure switch-min-oil
B15 Heavy oil immediate start B7 Pressure switch – valve proving

Function Address Number Data designation Ac- Data type / Range Updating
of cess coding rate
words
03/04 37 1 Outputs R U16 - Medium

Coding: 0 → inactive 1 → active

B15 B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0

B8 Fuel valve SV oil B0 Alarm

B9 Fuel valve V1 oil B1
B10 Fuel valve V2 oil B2
B11 Fuel valve V3 oil B3
B12 Fuel valve SV gas B4 Ignition
B13 Fuel valve V1 gas B5 Start signal / DW valve
B14 Fuel valve V2 gas B6 Fan
B15 Fuel valve PV gas B7 Oil pump / magnetic coupling

Function Address Number Data designation Access Data Data type / Range Updating
of format coding rate
words
R 03/04 38 1 Program stop R/W* U16 0=deactivated 0...7 Slow
W 06/16 1=24 PrePurgP
2=32 PrePFGR
3=36 IgnitPos
4=44 Interv 1
5=52 Interv 2
6=72 PostPPos
7=76 PostPFGR
R 03/04 39 1 Operating mode with load controller R/W* U16 0=ExtLR X5-03 0…5 Slow
W 06/16 1=IntLR
2=IntLR Bus
3=IntLR X62
4=ExtLR X62
5=ExtLR Bus
R 03/04 40 1 Selection of manual or automatic operation R U16 0=automatic 0…2 Fast
1=burner on
2=burner off
R 03/04 41 1 Modbus mode: Local / Remote R/W U16 0 = Local 0…1 Slow
W 06/16 1 = Remote

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Function Address Number Data designation Access Data Data type / Range Updating
of format coding rate
words
R 03/04 42 1 Modbus downtime: R/W* U16 0…7200 s Slow
W 06/16 Max. time with no communication. When this
time has elapsed, automatic changeover
from Remote to Local takes place
R 03/04 43 1 Operating mode in Remote mode. R/W U16 0 = Auto 0…2 Fast
W 06/16 Auto, Remote ON, Remote OFF 1 = ON
2 = OFF
R 03/04 44 1 External setpoint W3 R/W U16 PT_TEMP_ See ”Data Fast
W 06/16 Unit: See address 18 / 19 DRUCK types” on
page 15
R 03/04 45 1 Predefined output mod. / multistage R/W U16 PT_LEISTUNG See ”Data Fast
W 06/16 types” on
page 15
R 03/04 46 1 Fuel selection AZL... R/W* U16 0 = Gas 0…1 Slow
W 06/16 1 = Oil
R 03/04 47 1 Setpoint W1 R/W U16 PT_TEMP_ See ”Data Slow
W 06/16 DRUCK types” on
page 15
R 03/04 48 1 Setpoint W2 R/W U16 PT_TEMP_ See ”Data Slow
W 06/16 DRUCK types” on
page 15
R 03/04 49 1 Weekday R/W U16 0 = Sunday 0…6 Slow
W 06/16 1 = Monday
...
R 03/04 50 3 Date R/W U16[3] Data structure Slow
W 16 Date
R 03/04 53 3 Time of day R/W U16[3] Data structure Slow
W 16 Time of day
R 03/04 56 2 Hours run gas (adjustable) R/W* S32 0...999999 h Slow
W 16
R 03/04 58 2 Hours run oil stage 1 or modulating R/W* S32 0...999999 h Slow
W 16 (adjustable)
R 03/04 60 2 Hours run oil stage 2 or modulating R/W* S32 0...999999 h Slow
W 16 (adjustable)
R 03/04 62 2 Hours run oil stage 3 or modulating R/W* S32 0...999999 h Slow
W 16 (adjustable)
R 03/04 64 2 Hours run total (can be reset) R/W* S32 0...999999 h Slow
W 16
03/04 66 2 Hours run total (read only) R S32 0...999999 h Slow
03/04 68 2 Hours run device connected to power R S32 0...999999 h Slow
(read only
R 03/04 70 2 Startup counter gas (adjustable) R/W* S32 0...999999 Slow
W 16
R 03/04 72 2 Startup counter oil (adjustable) R/W* S32 0...999999 Slow
W 16
R 03/04 74 2 Startup counter total (can be reset) R/W* S32 0...999999 Slow
W 16
03/04 76 2 Startup counter total (read only) R S32 0...999999 Slow
03/04 78 2 Fuel volume gas (read only) R/W* S32 See ”Data Slow
(resettable from AZL5... version V4.10) types” on
0…199999999.9 m³ page 15
0…1999999999 ft³

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Function Address Number Data designation Access Data Data type / Range Updating
of format coding rate
words
03/04 80 2 Fuel volume oil (read only) R/W* S32 See ”Data Slow
(resettable from AZL5... version V4.10) types” on
0…199999999.9 l page 15
0…199999999.9 gal
03/04 82 1 Number of lockouts R U16 0…65535 Slow
03/04 83 1 Extra temperature sensor R U16 °C: *1 0..2000 °C Slow
(from AZL5... version V4.10) °F: *1 32..3632 °F

Parameters 84...137 are available from AZL5... version V4.20

03/04 84 8 AZL5... ASN R U8[16] String Constant

03/04 92 1 AZL5... parameter set code R U16 Constant
03/04 93 1 AZL5... parameter set version R U16 Constant
03/04 94 3 AZL5... identification date R U16[3] Date Constant
03/04 97 1 AZL5... identification number R U16 Constant
03/04 98 8 Burner control ASN R U8[16] String Constant
03/04 106 1 Burner control parameter set code R U16 Constant
03/04 107 1 Burner control parameter set version R U16 Constant
03/04 108 3 Burner control identification date R U16[3] Date Constant
03/04 111 1 Burner control identification number R U16 Constant
03/04 112 1 Software version AZL5... R U16 Hexadecimal Constant
03/04 113 1 Software version burner control R U16 Hexadecimal Constant
03/04 114 1 Software version load controller R U16 Hexadecimal Constant
03/04 115 8 Burner identification R U8[16] String Upon
reset
03/04 123 1 Min-output gas R U16 PT_LEISTUNG 0...100 % Slow
03/04 124 1 Max-output gas R U16 PT_LEISTUNG 0...100 % Slow
03/04 125 1 Min-output oil R U16 PT_LEISTUNG 0...100 % Slow
1001...1003
03/04 126 1 Max-output oil R U16 PT_LEISTUNG 0...100 % Slow
1001...1003
R 03/04 127 1 Load limitation enduser (modulating) R/W* U16 PT_LEISTUNG 0...100 % Slow
W 16
R 03/04 128 1 Load limitation enduser (multistage) R/W* U16 0: S1 0...2 Slow
W 16 1: S2
2: S3
03/04 129 1 Temperature limiter switching differential ON R S16 PT_Prozent1 -50...0 % Slow
(in address 29: Temperature limiter OFF
threshold, in degrees Celsius / Fahrenheit)
03/04 130 1 Measuring range temperature sensor R U16 0: 150°C / 302°F 0...2 Slow
1: 400°C / 752°F
2: 850°C / 1562F
03/04 131 1 Adaption active / inactive R U16 0: Inactive 0...1 Fast
1: Active
03/04 132 1 Adaption state R U16 PT_ADAPTION 0...12 Slow
R 03/04 133 1 Start adaption R/W U16 0: Reset value 0...2 Slow
W 16 1: Start
2: Abort
R 03/04 134 1 Adaption output R/W* U16 PT_Prozent1 40...100 % Slow
W 16 Permissible values: 40 %, 50 %, 60 %,
70 %, 80 %, 90 %, 100 %
R 03/04 135 1 P-value R/W* U16 PT_Prozent01 2...500 % Slow
W 16
R 03/04 136 1 I-value R/W* U16 Seconds 0...2000 s Slow
W 16

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Function Address Number Data designation Access Data Data type / Range Updating
of format coding rate
words
R 03/04 137 1 D-value R/W* U16 Seconds 0...1000 s Slow
W 16
03/04 400 16 Lockout history (current lockout) R U16/U32 [] Fast
03/04 416 16 Lockout history (current lockout -1) R U16/U32 [] Fast
03/04 432 16 Lockout history (current lockout -2) R U16/U32 [] Fast
: : : : : :
03/04 528 16 Lockout history (current lockout -8) R U16/U32 [] Fast
03/04 544 8 Error history (current error) R U16/U32 [] Fast
03/04 552 8 Error history (current error -1) R U16/U32 [] Fast
: : : : : :
03/04 704 8 Error history (current error -20) R U16/U32 [] Fast

* These parameters need not be continually written since they are stored in EEPROM,
which only permits a limited number of write accesses over its lifecycle (< 100,000)
Data structures
Date U16 Year
Month
Day

Time of day U16 Hour

Minute
Second

Lockout history U16 Error code

Error diagnostics
Error class
Error phase
Fuel
Output
Date: Year
Date: Month
Date: Day
Time of day: Hours
Time of day: Minutes
Time of day: Seconds

U32 Startup counter total

Hours run total

Error history U16 Error code

Error diagnostics
Error class
Error phase
Fuel
Dummy
Output

U32 Startup counter total

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Legend to address table

Access R Value can only be read

R/W Value can be read and written

Data format U16 16 bit integer, not subject to sign

S32 32 bit integer, subject to sign
Note:
In the AZL..., this data type is also used to
mark an invalid or non-available value by
using the value of «-1»

[] Data array

¹) Refer to section «Data structures»

* These parameters need not be continually written since they are stored in EEPROM,
which only permits a limited number of write accesses over its lifecycle (< 100,000)

Data types

TYPE Phys. Int. range Resolution Conversion int. / phys.

PT_PROZENT01 0...100 % 0...1000 0.1 % / 10
PT_PROZENTFU 0...110 % 0...1100 0.1 % / 10
PT_WINKEL -3.0...93.0° -30...930 0.1° / 10
PT_TEMP_ 0...2000° 0...2000 1 °C 1
DRUCK 32...3632 °F 32...3632 1 °F 1
0...100 bar 0...1000 0.1 bar / 10
0...1449 psi 0...1449 1 psi 1
PT_LEISTUNG Modulating opera- 0...1003 Modulating Modulating operation:
tion: 0...100 % operation: / 10
Multistage opera- 0.1 %
tion: Multistage operation:
1001 = stage 1 Multistage - 1000
1002 = stage 2 operation:
1003 = stage 3 1
PT_ADAPTION 0: Undefined
1: Identification completed, parameter determined
2: Undefined
3: Adaption aborted by user
4: Temperature differential too small, temperature will be lowered with low-fire
5: Monitoring time running
6: Delivery of identification load set
7: Error during identification (path)
8: Error during identification (internally)
9: Monitoring time running
10: Changeover from modulating to multistage during an identification
11: Timeout monitoring time
12: Timeout heating output on path with monitoring

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Starting adaption via Modbus

The routine used for identifying the path in the integrated load controller (termed “adap-
tion“ here) of the LMV5... system can be controlled and monitored via Modbus.

In principle, the general conditions are the same as those used when making adaptions
with the AZL52... (refer to subsection 6.4.2 Self-setting of control parameters (adap-
tion)) in the Basic Documentation of the LMV5... system (P7550).

The terms Start adaption, Adaption active / inactive and Adaption state indicate the
respective Modbus addresses (refer to ”Table of addresses”).

Start the adaption via Start adaption and change the value from ≠ 1 to = 1.
Starting the adaption has no impact on adaption processes already under way
(Adaption active / inactive = 1).

If Adaption active / inactive = 1, the process can be monitored via Adaption state (refer
to data type PT_ADAPTION).
When Adaption active / inactive = 0, the adaption process is completed.
On completion of the process, the result can be read out via Adaption state.

To complete the adaption process prematurely, the value at Start adaption must be
changed from ≠ 2 to = 2.

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Updating rate of AZL...
Fast System data that have already been updated automatically by the system process are
available on request, at a typical repetition rate of 200 ms.

Medium These data are cyclically queried in the system by the AZL... The typical updating rate
here is 5 seconds, depending on system load.

Slow These data are cyclically queried in the system by the AZL... The typical updating rate
that can be expected here is 25 seconds, depending on system load.

Constant These data are updated in the system by the AZL5... upon each Power On or reset.
When making a query, the updated data will be available after 25 seconds.
Data that cannot be changed (e.g. the production date, etc.) – neither with the AZL5...
nor via the ACS450 – can be identified by the value of 0 in the first Byte of the strings.

Upon reset Same as constant data, but these data can be changed in the system.

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Error handling
Error codes When there are faulty telegrams (CRC errors, etc.), the AZL… does not send any ex-
ception code. It does not respond to this kind of message.

Reason: Usually, the commercially available Modbus drivers do not respond to excep-
tion codes.

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Selection menus in the AZL...

Activation of Modbus operation

Activation takes place via menu

«Operation» → «OptgModeSelect» → «GatewayDDCon».

Having made the selection, the menu item can be quit via ESC. The setting is retained
until «Operation» → «OptgModeSelect» → «GatewayDDCoff» is selected via the
AZL… menu.

When «GatewayDDCon» is activated, plant operation and diagnostics via the AZL...
are still possible.

Deactivation takes place via menu

«Operation» → «OptgModeSelect» → «GatewayDDCoff».

Slave address

Selection is made via menu

«Params & Display» → «AZL» → «Modbus» →«Address».

According to Modicon specifications, addresses between 1...247 can be selected. The

slave address is filed in nonvolatile memory of the AZL...

Transmission parameters

Transmission rate The setting is made via menu

«Params & Display» → «AZL» → «Modbus» → «Baud Rate»
There is a choice of 9600 bit/s or 19200 bit/s.

Parity Using the AZL... menu

«Params & Display» → «AZL» → «Modbus» → «Parity», parity can be set to «none»,
«even» or «odd».

Timeout communication failure

When there is no Modbus communication, this timeout defines the period of time on
completion of which the AZL… changes automatically from Remote to Local.

The setting is made via menu

«Params & Display» → «AZL» → «Modbus» → «Downtime».

Local «-» Remote mode

This setting defines whether the AZL… shall work in Local or Remote mode.

Remote mode

Display of «Remote Auto», «Remote On», «Remote Off» mode. A change can only be
made via Modbus.

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AZL5... interface

General

The AZL... serves the Modbus via its COM2 port (8-pole Western jack RJ45). The port
is assigned to the functional low-voltage range.

Assignment of RJ45 pins:

PIN
1 TXD (RS-232 level or V28)
2 Not used
3 RXD (RS-232 level or V28)
4 GND
5 U1 (typically +8.2V)
6 GND
7 U2 (typically -8.2V)
8 Not used

When preparing and fitting a connecting cable between the AZL... and a converter, it is
to be noted that PIN 5 and PIN 7 can deliver a current of 5 mA each. Adequate insula-
tion against other potentials must be ensured.

The maximum permissible data line length between COM2 and a converter is 3 m. In
exceptional cases, this data line length can be exceeded, depending on environmental
conditions (electrical interference) and the type of cable used – without Siemens as-
suming responsibility.

To ensure protection against electric shock hazard, it must be made certain that AC
230 V / AC 120 V lines are strictly separated from the functional low-voltage area.

CAN X70 COM2 X72

PIN PIN
2 CAN L COM 2 1 TXD
CAN
3 GND 3 RXD
8 7
4 VAC 2 9 6
8 1
4, 6 GND
5 1
7 CAN H 4 3 2
5 U1
8 VAC 1 7 U2
X70 X72

COM 1
COM1 X71

PIN 6
7 8
9 X71
7550z09/0703

1 5
2 RXD 2 3 4

3 TXD
5 GND

Note COM1 (PC port) ad COM2 cannot be active at the same time!

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Converter RS-232 – RS-485
This converter converts a V.24 / RS-232 port into an RS-485 port.

Technical requirements

– Code transparency, that is, data must remain unchanged

– When using the RS-485 interface as a bus, control of the transmitting section on the
RS-485 side must be ensured by the transmitter power of the AZL...
– The interfaces must be galvanically separated to improve EMC

Commercially available converters

The technical specification provided by the suppliers of the converters must be ob-
served when doing planning work. Some of them do not meet the specifications of the
LMV5... system (e.g. operating temperatures). If required, technical measures must be
taken (e.g. suitable location).
The following types of converters have been tested by us with respect to function and
immunity (voltage surges):

• Supplier: Hedin Tex

Type reference: H-4

Contact address in Germany:

Hedin Tex GmbH
Am Herrkamp 14
D-24226 Heikendorf
www.hedintex.de

• Supplier: IPC CON

Type reference: I-7520

Contact address in Germany:

Spectra Computersysteme GmbH, Humboldtstraße 36
D-70771 Leinfelden-Echterdingen
*www.spectra.de

Connection example: Connecting cable for interface converter type Hedin Tex H4/M4

Hedin Tex
AZL COM2 Cable interface converter
8-pole Western X1 RS-232
H4 M4
1 TxD 21 2
2 __ __ __

3 RxD 22 3
4 GND 16 7
5 U1 (only for eBus adapter)
6 GND __ __

7 U2 (only for eBus adapter)

8 __ __ __
7550t05e/0703

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Addendum 1: Overview of «Operating mode
changeover of controller»

7550d37e/0504
For Remote mode, load controller operating
mode:
AZL...
"IntLRBus" must be selected via the AZL... menu
or Modbus parameter no. 39

Selection of manual
or automatic operation
Manually Manually Modbus parameter no. 40 (read only)
"off" (2) "Auto" (0) (storage location: EEPROM AZL...)

Manually
"on" (1)

Modbus parameter no. 45 Preselected

(storage location: output
RAM AZL...)

Timeout behavior
Timeout Modbus parameter no. 42
(storage location: EEPROM AZL...)

Local (0) Remote (1) Modbus parameter no. 41

(storage location: RAM AZL...)

Modbus parameter no. 47

W1
(storage location: EEPROM LR)

Operating mode selection

in Remote mode Remote Modbus parameter no. 43
Remote "Auto" (0) (storage location:
"off" (2) RAM AZL...)

Remote
"on" (1)

Modbus parameter no.45

Preselected
(storage location:
output W3
RAM AZL...)

Modbus parameter no. 44

(storage location: RAM AZL...)

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Notes on operating modes

Modbus downtime

When there is no more communication between DDC and AZL..., the Modbus down-
time is used to switch over from Remote mode to the preselected setpoint in Local
mode. The timer will be activated when changing from Local to Remote. With every
permissible Modbus communication to this slave (AZL...), the timer will be reloaded.
Should the timer lapse, the DDC must again set the Remote mode, if required. The
timer value will be retained in EEPROM and will also be retained after power off.

Note When deactivating the «Gateway DDC» mode (menu item «OptgModeSelect» →
«GatewayDDCoff»), automatic changeover to Local takes place, that is, preselected
output «W1» will apply.

Changeover of operating mode via parameter 43

This changeover was introduced primarily because of the requirements of boiler se-
quence control.
In that case, the individual boiler can be operated at low output via manually «On».
When switching to «Auto» via sequence control, preselected output «W3» will be used.

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Addendum 2: Default parameter settings
Parameter Address Storage location Preselection Choices for making
changes
Setpoint W1 47 EEPROM See Basic Documenta- • On the AZL...
tion «Menu and pa- (menu)
rameter lists» • Preselection via
Modbus
Setpoint W2 48 EEPROM See Basic Documenta- • On the AZL...
tion «Menu and pa- (menu)
rameter lists» • Preselection via
Modbus
External setpoint W3 44 RAM «0» will be reinitialized • On the AZL...
when resetting the (menu)
AZL... • Preselection via
Modbus
Set target load mod / 45 RAM «0» will be reinitialized • On the AZL...
multistage when resetting the (menu)
AZL... • Preselection via
Modbus
Local / Remote 41 RAM «Local» • Via Modbus
• On the AZL...
(menu)
• Via lapse of timer
«Communication
failure» from Re-
mote to Local
Selection of manual 40 EEPROM See Basic Documenta- • On the AZL...
or automatic opera- tion «Menu and pa- (menu)
tion rameter lists»
Operating mode: 43 RAM «Auto» will be reinitial- • Preselection via
Remote ”off” / re- ized when resetting the Modbus
mote “on” / W3 AZL...
Operating mode with 39 EEPROM See Basic Documenta-
load controller tion «Menu and pa-
rameter lists»

Note An AZL… reset will be triggered when switching power on, or in the event of severe
system errors.

©2007 Siemens Building Technologies HVAC Products GmbH

Subject to change! 23/23

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