Elster BCU 480 User manual

6.1.2.8 Edition 06.07
Technical Information · GB
www.kromschroeder.com
For pilot and main burners of unlimited capacity in intermittent or continuous•
operation pursuant to EN 746-2
Automatic burner control unit, ignition transformer, indicators and operating•
controls in a space-saving metal housing which replaces the local burner
control cabinet
Flame control by UV, ionisation or a further option of using the furnace•
chamber temperature
Display of the program status, unit parameters and flame signal; Manual•
mode for burner adjustment and for diagnostic purposes
Visualisation and adaptation to the specific application via the PC•
programming and diagnostic software BCSoft to simplify logistics
management
Spacious connection chamber with plug-in terminal blocks and plug-in cable•
glands for quick installation and servicing
Air valve control relieves the furnace control•
Optional PROFIBUS-DP interface•
EC type-tested and certified•
Burner control units BCU 480

BCU 480 · Edition 06.07
2
t= To be continued
Contents
Burner control units BCU 480 ....................... 1
Contents........................................2
1 Application.....................................4
2 Examples of application ..........................6
2.1 Stage-controlled main burner with alternating
pilot burner ......................................6
2.2 Stage-controlled main burner with permanent
pilot burner ......................................7
2.3 Two-stage-controlled main burner with permanent
pilot burner ......................................8
2.4 Modulating-controlled burner ....................9
2.5 BCU 480..B1 for PROFIBUS-DP ...................10
2.6 BCU 480..D:High temperature equipment .........10
3 Certification ....................................11
3.1 EC type-tested and certified ......................11
3.2 AGA .........................................11
3.3 FM ..........................................11
3.4 Profibus User Organisation ......................11
4 Function...................................... 12
4.1 Connection diagrams ..........................12
4.1.1 BCU 480.........................................12
4.1.2 BCU 480..B1 with Profibus ..........................13
4.1.3 BCU 480..P with 16-pin industrial plug connector .......14
4.2 BCU 480 program sequence ....................16
4.3 Program status and fault messages ..............19
5 Parameters ...................................20
5.1 Scanning the parameters . . . . . . . . . . . . . . . . . . . . . . . 21
5.2 Flame control.................................22
5.2.1 Flame signal, pilot burner ......................... 22
5.2.2 Flame signal, main burner ........................ 22
5.2.3 Program status when the most recent fault occurred .. 22
5.2.4 Switch-off threshold of the flame amplifier ........... 22
5.2.5 High temperature operation in the case of BCU..D2 or
BCU..D3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.2.6 UVS check...................................... 26
5.3 Pilot and main burner monitoring ................27
5.3.1 Permanent pilot burner ........................... 28
5.3.2 Interrupted pilot burner ........................... 28
5.4 Behaviour in start-up position/standby............29
5.4.1 Flame simulation check in start-up position/standby ... 29
5.4.2 Minimum burner pause time tBP ................... 30
5.5 Behaviour during start-up ......................31
5.5.1 Safety time on start-up tSA ..........................31
5.5.2 Flame proving period tFS ......................... 32
5.5.3 Minimum combustion time tB..................... 32
5.5.4 Burner start-up attempts.......................... 33
5.6 Behaviour during operation .....................35
5.6.1 Safety time during operation tSB for pilot and
main burners........................................ 35
5.6.2 Fault lock-out or restart, pilot burner ................ 35
5.6.3 Immediate fault lock-out following flame failure....... 35
5.6.4 Fault lock-out or restart, main burner.................37
5.7 Air valve control on BCU..L ......................39
5.7.1 Purge .......................................... 39
5.7.2 Cooling in start-up position/standby ................ 39
5.7.3 Burner start..................................... 39
5.7.4 Air valve opens in the case of external activation
(not during start-up) .................................. 40
5.7.5 Air valve opens in the case of external activation
(even during start-up) ..................................41
5.7.6 Air valve opens with valve V2 ...................... 42
5.7.7 Air valve opens with operating signal ............... 43
5.7.8 Low fire over run time tKN after a normal shut-down ... 44
5.7.9 Behaviour of the air valve in the event of a
fault lock-out ........................................ 45
5.8 Manual mode ................................46
5.8.1 Manual mode limited to 5 minutes.................. 46

BCU 480 · Edition 06.07
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t= To be continued
6 Selection .....................................47
6.1 Safety time ...................................47
6.1.1 Calculating the safety time tSA .......................47
6.2 Selection table................................48
7 Project planning information......................49
7.2.1 Cable selection .................................. 49
7.2.2 Ignition cable ................................... 49
7.2.3 Ionisation cable ................................. 49
7.2.4 UV cable ....................................... 49
7.1 Ignition electrode ..............................49
7.1.1 Electrode gap.................................... 49
7.1.2 Star electrodes .................................. 49
7.2 Minimum combustion time......................50
7.3 Safety interlocks (Limits).........................50
7.4 Emergency stop ...............................50
7.4.1 In the event of fire or electric shock .................. 50
7.4.2 Via the safety interlocks (limits) ..................... 50
7.5 Reset........................................51
7.5.1 Parallel reset .....................................51
7.5.2 Permanent remote reset ...........................51
7.5.3 Automatic remote reset (PLC) .......................51
7.5.4 Burner start ......................................51
7.5.5 Restart and start-up attempts .......................51
7.6 Fault signalling................................52
7.7 Protecting the pilot burner from overload ..........52
7.8 Installation ...................................53
7.9 Wiring .......................................53
7.10 BCU switched off .............................55
7.11 Furnace control ...............................55
7.12 Mains switch ................................55
7.13 Note on EC type-examination ...................55
7.14 Changing parameters .........................56
8 Flame control .................................57
8.1 With ionisation sensor ..........................57
8.2 With UV sensor ...............................57
8.3 Via the temperature in high temperature
equipment ......................................57
9 Accessories ...................................58
9.1 High-voltage cable ............................58
9.2 16-pin industrial plug connector .................58
9.3 BCSoft.......................................58
9.4 “Changed parameters” stickers..................58
9.5 External securing bar ..........................59
9.6 Fastening set .................................59
9.7 Radio interference suppressed electrode adapters..59
10 Technical data ................................60
10.1 Housing dimensions ..........................62
10.2 Operating controls............................62
11 Legend ......................................63
12 Glossary.....................................64
12.1 Waiting time tW..............................64
12.2 Safety time on start-up tSA .....................64
12.3 Ignition time tZ...............................64
12.4 Flame simulation/Flame simulation delay time tLV ..64
12.5 Safety time during operation tSB ................64
12.6 Flame signal.................................65
12.7 Fault lock-out ................................65
12.8 Safety interlocks (Limits) ........................65
12.9 Pilot gas valve V1 .............................65
12.10 Main gas valve V2 ...........................65
12.11 Continuous operation.........................65
12.12 Air valve ...................................65
Feedback ......................................66
Contact........................................66

BCU 480 · Edition 06.07
4
Application1
The burner control units BCU 480 control, ignite and monitor
gas burners for intermittent or continuous operation. As a re-
sult of their fully electronic design they react quickly to various
process requirements and are therefore suitable for frequent
cycling operation.
They can be used for industrial burners of unlimited capacity
which are ignited by pilot burners. Pilot and main burners may
be modulating or stage-controlled. The BCU 480 monitors pilot
and main burners independently. The pilot burner can burn
permanently or be switched off. The BCU is installed near to
the burner to be monitored.
On industrial furnaces, the BCU reduces the load on the cen-
tral furnace control by taking over tasks that only relate to the
burner, for example it ensures that the burner always ignites
in a safe condition when it is restarted.
The air valve control assists the furnace control for cooling,
purging and capacity control tasks.
The program status, the unit parameters and the level of the
flame signal can be read directly from the unit. The burner
can be controlled manually for commissioning and diagnostic
purposes.
If the local requirements on the burner control unit change, the
PC software “BCSoft” can be adjusted to the unit parameters
of the application by using the optical interface.
The service personnel is supported by a convenient visuali-
sation system of the input and output signals and the error
history.
The BCU unites the
functionally interre-
lated components
of automatic burner
control unit, igni-
tion transformer,
Manual/Automatic
mode and display
of operating and
fault statuses in
a compact metal
housing.
t

BCU 480 · Edition 06.07
5
To reduce the installation and wiring costs, Elster Kromschröder
offers an optional PROFIBUS-DP interface to transfer the ac-
tivation signals and feedbacks so as to expand the remote
servicing and diagnostics facilities.
Bogie hearth forg-
ing furnace in the
metallurgical in-
dustry
Intermittent shuttle
kiln in the ceramics
industry
Walking beam
furnace with over-
head firing
Application

BCU 480 · Edition 06.07
6
BCU 480
14 12
23
26
SPS
PLC
API
DI
L1, N, PE
P
22 4 21 18
19
16
17
28
29
24
2
1
t
1
2
A
P
5
3
DI
6
02–0402–04 06–08 06–08
ϑ 2
ϑ 1
ϑ 1
ϑ 2
µC
VR..L
VAG
UV
VBY
2
1
Examples of application2
Stage-controlled main burner2.1
with alternating pilot burner
Control:
Main burner ON/OFF.
The main burner can be started with re-
duced capacity after the operating signal
from the pilot burner has been detected.
The pilot burner is switched off automati-
cally after the main burner has started
up. When the main burner is switched off,
the pilot burner automatically switches
on again. This reduces the main burner
start-up time.
A UV sensor monitors the flame signal
from pilot and main burners. UV sensor
UVD 1 is used for continuous operation,
UV sensor UVS for intermittent opera-
tion.
The BCU provides the cooling and purg-
ing processes.

BCU 480 · Edition 06.07
7
t
1
2
BCU 480
14 12
23
26
SPS
PLC
API
DI
L1, N, PE
P
22 4 21 18
19
16
17
28
29
24
2
1
A
P
5
3
DI
6
0402–04 06–08 06–08 04
µC
ϑ 1 ϑ 2
ϑ 1
ϑ 2
VR..R
VAG
VBY
2
1
Stage-controlled main burner 2.2
with permanent pilot burner
Control:
Main burner ON/OFF.
The main burner can be started with
reduced capacity after the operating
signal from the pilot burner has been
detected. Pilot and main burners can be
operated simultaneously. This reduces
the time required by the main burner
for starting up.
The BCU provides the cooling and purg-
ing processes.
Examples of application

BCU 480 · Edition 06.07
8
BCU 480
12
23
SPS
PLC
API
DI
L1, N, PE
P
22 4 21 18
19
16
17
28
29
24
2
1
A
P
5
3
DI
6
VBY
µC
ϑ 1 ϑ 2
t
1
2
0402–04 06–08 06–08 04
ϑ 1
ϑ 2
2
1
BV
IC 40
4
7
M
14
26
50 51
VAG
VAS
Two-stage-controlled main2.3
burner with permanent pilot
burner
Control:
Main burner ON/OFF with ignition via
bypass.
The main burner can be started at low-
fire rate after the operating signal from
the pilot burner has been detected. When
the operating state is reached, the BCU
issues the Enable signal for the maxi-
mum burner capacity. Pilot and main
burners can be operated simultaneously.
This reduces the time required by the
main burner for starting up.
The BCU provides the cooling and purg-
ing processes.
Examples of application

BCU 480 · Edition 06.07
9
BCU 480
14 12
SPS
PLC
API
DI
L1, N, PE
4 21 18
19
16
17
28
29
24
2
1
P
5
3
DI
6
mA
µC
ϑ 1
ϑ 2
VAG
VBY
BV+IC
M
2
1
Modulating-controlled burner 2.4
Control:
Main burner continuous
The butterfly valve for air is moved to ig-
nition position in order to start the main
burner. The main burner can be started
at low-fire rate after the operating signal
from the pilot burner has been detected.
The control system controls the burner
capacity via the butterfly valve for air
after the operating state has been sig-
nalled. Pilot and main burners can be
operated simultaneously. This reduces
the time required by the main burner
for starting up.
Examples of application

BCU 480 · Edition 06.07
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PROFIBUS-DP
BCU 480..B
BUS
1–6
BCU 480..B
BUS
BCU 480..B
BUS
1–61–6
SPS
PLC
API
DI
L1, N, PE
P
BUS
STW
L1
DI
BCU 480..D
DI
>750 °C
6
924
BCU 480..D
6
924
µC µC
BCU 480..B1 for PROFIBUS-DP2.5
The bus system transfers the control
signals for starting, resetting and for
controlling the air valve from the control
system to the BCU 480..B1. In the oppo-
site direction it sends operating status,
the level of the flame signals and the
current program status.
Control signals that are relevant for safety,
such as the safety interlocks, purge (op-
tional) and digital input, are transferred
independently of the bus communication
by separate cables.
BCU 480..D:2.6
High temperature equipment
Indirect flame control using the tempera-
ture. During the start-up process, as long
as the wall temperature is below auto
ignition temperature the flame must be
controlled by conventional methods.
When the working temperature has ex-
ceeded 750°C, the safety temperature
monitor (STW) takes over the indirect
flame control.
Examples of application