Krom Schroder BCU 560 Manual

6 Edition 02.16
Technical Information · GB
Burner control units BCU 560, BCU 565
• For monitoring and controlling modulating or staged burners for multiple
burner applications with a central air supply
• For directly ignited burners of unlimited capacity in intermittent or
continuous operation
• Optionally with valve proving system
• Optionally with menox®operating mode to reduce the formation of
thermal NOx
• Flexible range of applications due to parameterization possibilities
• PROFINET fieldbus connection using optional bus module
• Assume safety functions pursuant to EN746-2
• EU certified
• Certified for systems up to SIL 3 and PL e

BCU 560, BCU 565 · Edition 02.16 2
▼= To be continued
Contents
Burner control units BCU 560, BCU 565 ............... 1
Contents........................................2
1 Application.....................................5
1.1 Examples of application..........................7
1.1.1 Single-stage-controlled burner........................7
1.1.2 Two-stage-controlled burner ........................ 8
1.1.3 Modulating-controlled burner ........................9
1.1.4 Flame control using the temperature .................10
1.1.5 menox®mode to reduce NOxformation ..............11
1.1.6 PROFINET connection using bus module BCM ..........12
1.1.7 ON/OFF rotary impulse control for burners up to 360kW . 13
1.1.8 Modulating burner control . . . . . . . . . . . . . . . . . . . . . . . . . .14
2 Certification ................................... 15
3 Function...................................... 16
3.1 Connection diagram ...........................16
3.1.1 BCU560..F3 with ionization control in double-electrode
operation ............................................16
3.1.2 BCU560..F1......................................17
3.1.3 BCU560..F2 .....................................18
3.1.4 BCU565..F3 with ionization control in double-electrode
operation ............................................19
3.1.5 BCU565..F1..................................... 20
3.1.6 BCU565..F2 .....................................21
3.1.7 Flame control ................................... 22
3.2 BCU 560 program sequence ....................23
3.3 BCU 565 program sequence ....................24
4 Air control ....................................25
4.1 Capacity control ...............................26
4.1.1 BCU..F1/F2 ...................................... 26
4.1.2 BCU..F3 .........................................27
5 menox®low NOxmode .........................28
5.1 System structure and function....................28
5.2 BCU..D2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
6 Valve proving system ........................... 31
6.1 Tightness control ..............................31
6.1.1 Test instant...................................... 32
6.1.2 Program sequence............................... 33
6.1.3 Test period tP................................... 35
6.1.4 Opening time tL................................. 35
6.1.5 Measurement time tM............................ 35
6.2 Proof of closure function........................38
6.2.1 Program sequence............................... 38
7 BCSoft .......................................39
8 Profinet ......................................40
8.1 BCU and bus module BCM......................41
8.2 GSD file for PLC configuration....................42
8.2.1 Modules for cyclic data exchange .................. 43
8.2.2 Indexes for acyclic communication ................. 48
9 Program step/status............................49
10 Fault signalling................................50
11 Parameters...................................53
11.1 Scanning the parameters.......................58
11.2 Flame control ................................58
11.2.1 Burner 1 FS1 flame signal switch-off threshold......... 58
11.2.2 Flame control................................... 59
11.2.3 High temperature operation ...................... 60
11.3 Behaviour during start-up ......................62
11.3.1 Burner 1 start-up attempts......................... 62
11.3.2 Burner application............................... 63
11.3.3 Safety time 1 tSA1 ............................................71
11.3.4 Flame proving period 1 tFS1 ........................71
11.4 Behaviour during operation.....................72
11.4.1 Restart..........................................72
11.4.2 Minimum operating time tB........................73
11.5 Safety limits ..................................74
11.5.1 Low air pressure protection ....................... 74
11.5.2 Air pressure cut-out delay ........................ 74
11.5.3 Safety time during operation .......................75
11.6 Air control ...................................76

BCU 560, BCU 565 · Edition 02.16 3
Contents
11.6.1 Pre-purge time tPV ................................76
11.6.2 Air flow monitoring during pre-purge ................76
11.6.3 Pre-ventilation time tVL..................................... 77
11.6.4 Post-ventilation time tNL ................................... 77
11.6.5 Capacity control..................................78
11.6.6 Running time selection ........................... 85
11.6.7 Running time ................................... 85
11.6.8 Low fire over-run ................................ 86
11.6.9 Controller enable signal delay time tRF .............. 86
11.6.10 Air actuator control ..............................87
11.6.11 Air actuator can be activated externally on start-up ... 89
11.6.12 Air actuator in the event of fault ................... 89
11.6.13 Capacity control (bus) ........................... 90
11.7 menox®................................................95
11.7.1 menox pre-ventilation time tVLM .................... 95
11.7.2 Switchover to menox®operating mode ............. 95
11.8 Valve check..................................96
11.8.1 Valve proving system ............................ 96
11.8.2 Relief valve (VPS) ................................ 96
11.8.3 Measurement time Vp1 ...........................97
11.8.4 Valve opening time tL1 ............................97
11.9 Behaviour during start-up ......................98
11.9.1 Minimum pause time tBP ......................... 98
11.10 Manual mode ...............................99
11.10.1 Operating time in Manual mode .................. 99
11.11 Functions of terminals 50, 51, 65, 66, 67 and 68 ..100
11.11.1 Function of terminal 50 ...........................100
11.11.2 Function of terminal 51 ...........................100
11.11.3 Function of terminal 65 ..........................100
11.11.4 Function of terminal 66 ..........................101
11.11.5 Function of terminal 67...........................102
11.11.6 Function of terminal 68 ..........................103
11.12 Password..................................104
11.13 Fieldbus communication .....................104
12 Selection.................................... 105
12.1 Type code ..................................105
13 Project planning information.................... 106
13.1 Installation..................................106
13.2 Commissioning .............................106
13.3 Electrical connection ......................... 107
13.3.1 OCU ..........................................107
13.3.2 Safety current inputs.............................108
13.3.3 UVD control....................................109
13.4 Actuators .................................. 110
13.4.1 IC20..........................................110
13.5 Parameter chip card ......................... 110
13.6 Overload protection.......................... 110
13.7 Calculating the safety time tSA.........................111
13.8 Fourth or switchable gas valve on BCU..F3 ........112
14 Accessories ..................................113
14.1 BCSoft ..................................... 113
14.1.1 Opto-adapter PCO 200 ...........................113
14.1.2 Bluetooth adapter PCO 300 .......................113
14.2 OCU ...................................... 113
14.3 Connection plug set.......................... 113
14.4 Stickers for labelling.......................... 114
14.5 “Changed parameters” stickers ................ 114
15 OCU ........................................115
15.1 Application ................................. 115
15.2 Function ....................................116
15.2.1 Manual mode ..................................116
15.3 Electrical connection ..........................117
15.4 Installation ..................................117
15.5 Selection ....................................117
15.6 Technical data for OCU ....................... 118
16 BCM 500 ....................................119
16.1 Application ................................. 119
16.2 Function ................................... 119
16.3 Electrical connection ......................... 119
16.4 Installation ................................. 119
16.5 Selection ...................................120
16.6 Technical data ..............................120

BCU 560, BCU 565 · Edition 02.16 4
Contents
17 Technical data ................................121
17.1 Electrical data ............................... 121
17.2 Mechanical data ............................122
17.3 Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
17.4 Dimensions.................................122
17.5 Safety-specific characteristic values .............123
17.6 Converting units .............................124
18 Maintenance ................................ 125
19 Legend ..................................... 126
20 Glossary ................................... 127
20.1 Safety time on start-up tSA1 .................... 127
20.2 Ignition time tZ............................. 127
20.3 Safety time during operation tSB ..................... 127
20.4 Safety interlocks ............................ 127
20.5 Safety shut-down ........................... 127
20.6 Safety shut-down with subsequent fault lock-out
(fault lock-out) .................................. 127
20.7 Warning signal .............................128
20.8 Timeout ...................................128
20.9 Lifting .....................................128
20.10 Air valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
20.11 Diagnostic coverage DC .....................128
20.12 Operating mode ...........................128
20.13 Safe failure fraction SFF ......................129
20.14 Probability of dangerous failure PFHD.........129
20.15 Mean time to dangerous failure MTTFd........129
Feedback .....................................130
Contact.......................................130

BCU 560, BCU 565 · Edition 02.16 5
1 Application
Burner control unit with plug-in spring force connection terminals
Burner control units BCU 560 or BCU 565 control, ignite and
monitor gas burners in intermittent or continuous operation.
They can be used for directly ignited industrial burners of
unlimited capacity. The burners may be modulating-controlled
or stage-controlled. Their fast reaction to various process
requirements makes the BCUs suitable for frequent cycling
operation.
On industrial furnaces, they reduce the load on the central
furnace control by taking over tasks that relate to the burner, for
example they ensure that the burner ignites in a safe condition
when it is restarted.
The air control on the BCU..F1, F2 or F3 assists the furnace
control for cooling, purging and capacity control tasks.
The burner control units have an interface via which an air
valve or actuator (IC20, IC40 or RBW) can be controlled for
staged or modulating burner capacity control.
The BCU 565..F3 is equipped with air flow monitoring and
pre- and post-ventilation for use on self recuperative burners.
The program status, the unit parameters and the level of the
flame signal can be read directly from the unit. The burner or a
connected control element can be activated manually using the
integrated Manual mode for setting and diagnostic purposes.
Thanks to the optionally integrated valve proving system, the
valves can be checked for leaks by querying an external gas
pressure switch or it can be checked whether the gas valve
on the inlet side is closed.
Using the BCSoft program, the parameters, analysis and
diagnostic information can be read from a BCU via the
optionally available opto-adapter. All valid parameters are
saved on an integrated parameter chip card. The parameter
chip card can be removed from the old unit and inserted into
a new BCU to transfer the parameters, for example when
replacing the unit.
▼

BCU 560, BCU 565 · Edition 02.16 6
Application
The monitored outputs for the actuator and valves are ac-
commodated in a plug-in power module. This can simply be
replaced if necessary.
Once the plug-in power module has been removed, the
parameter chip card and fuses are accessible.
The BCU can be installed on a DIN rail in the control cabinet.
Plug-in connection terminal strips on the BCU make it easier
to install and remove.
Thanks to the operator-control unitOCU, display functions and
operation of the BCU can be relocated to the control cabinet door.
The external operator-control unitOCU is available as an option
for the burner control units. The OCU can be installed in the
control cabinet door instead of standard control units. The
program status or fault messages can be read on the OCU. For
burner adjustment, the operating points can be approached
conveniently in Manual mode using the operator-control unit.
The address for the fieldbus communication is set using
three code switches.
The optional bus module BCM500 makes it possible to con-
nect the BCU to a fieldbus interface in a PROFINET network.
Networking via the fieldbus enables multiple BCUs to be con-
trolled and monitored by an automation system (e.g.PLC). The
bus module is prepared for DIN rail installation. It is pushed
on to the BCU from the side.

BCU 560, BCU 565 · Edition 02.16 7
Application
1.1 Examples of application
1.1.1 Single-stage-controlled burner
Control: ON/OFF.
The gas/air mixture is adjusted to the requirements of the
applications using the parameters of pre-ventilation and post-
ventilation. The pressure switch monitors the air flow in the air
supply line or in the flue gas exhaust.
PDZ
BCU 565..F3
µC
VG
VG..L
TZI/TGI
VR..R
V1 V2
14
13
9
10
47
38371817 1 2 3
46
49
50
41
42
ECOMAX
FCU 500
Process control (PCC)
ϑ
A
P
HT
VMV
DG
PLC

BCU 560, BCU 565 · Edition 02.16 8
1.1.2 Two-stage-controlled burner
Control:
ON/OFF or High/Low
The BCU provides the cooling and purg-
ing processes. The burner starts at low-
fire rate. When the operating state is
reached, the BCU advises the control
unit. Depending on the parameter set-
ting, the air valve is actuated to open
and close by the program or externally
via the input at terminal 2.
Application > Examples of application
BCU 560..C0F3
µC
VAS VAG
TZI/TGI
VR..L
V1 V2
14
13
9
7
10
UVS
38371817 1 2 3
FCU 500
Process control (PCC)
46
49
50
P
HT
ϑ
41
42
A
PLC

BCU 560, BCU 565 · Edition 02.16 9
Application > Examples of application
1.1.3 Modulating-controlled burner
Control: continuous
The BCU provides the cooling and purg-
ing processes. The BCU moves the but-
terfly valve for air to ignition position. The
burner starts at low-fire rate, a three-
point step controller controls the burner
capacity via the butterfly valve for air after
the operating state has been signalled.
BCU 560..C0F1
µC
VAS VAG
TZI/TGI
V1 V2
V3
14
15
13
9
7
UVS
38371817 1 2 3
46
49
50
41
42
M
52 53 54 55 56
VAS 1
Process control (PCC)
ϑ
A
P
DI
FCU 500 PLC

BCU 560, BCU 565 · Edition 02.16 10
Application > Examples of application
1.1.4 Flame control using the temperature
FCU 500..H1
M
HT
18
HT
HT
BCU 56x..D
49
5
µC
BCU 56x..D
49
5
µC
5-8
STM
In high temperature systems (temperature >750°C), the flame
may be controlled indirectly via the temperature. As long as
the temperature in the furnace chamber is below 750°C, the
flame must be controlled by conventional methods.
If the temperature in the furnace chamber rises above the
spontaneous ignition temperature of the gas/air mixture
(>750°C), the FCU signals to the burner control units via the
fail-safe HT output that the furnace system is in High tempera-
ture mode (HT). When the HT input is activated, the burner
control units switch to High temperature mode. They operate
without evaluating the flame signal and their internal flame
control is non-functional.
If the furnace temperature falls below the spontaneous ignition
temperature (<750°C), the FCU disconnects the HToutput
from the electrical power supply. There is no longer an active
signal at the HT inputs of the burner control units. The flame
signals are monitored once again by the UV sensor or ioniza-
tion electrode.
In the event of a fault in a temperature monitoring component
(e.g. sensor discontinuity, sensor short-circuit) or in the event
of a mains failure, the flame control task is transferred to the
burner control units.

BCU 560, BCU 565 · Edition 02.16 11
Application > Examples of application
1.1.5 menox®mode to reduce NOxformation
VAD
BIC..M
IC 40 + BVH
M
VAS..L
VMV
DG
BCU 565..D2
PZL
Process Control (PCC)
AKT
TZI/
TGI
STM
The burner control unit BCU 565 switches the burner BIC..M
ON/OFF in cycles. Burner BIC..M is controlled without pneu-
matic air/gas ratio control system. The gas supply pressure
is controlled by the gas pressure regulatorVAD; the required
burner capacity is set using the fine-adjusting valveVMV. The
capacity is controlled by actuator IC40 and butterfly valveBVH.
An air pressure switch upstream of the burner monitors the
functioning of the butterfly valve. In addition, air/gas ratio
monitoring for the zone or the furnace is required.
As soon as the safety temperature monitor STM signals a
furnace temperature of ≥850°C(1562°F), the burner can be
switched to flameless combustion (menox®low NOxmode)
to significantly reduce NOxemissions.
Switching to menox®low NOxmode eliminates the counter-
pressure by the flame in the ceramic tubeTSC. At a constant
gas supply pressure, the gas volume increases by approxi-
mately15%. In menox®low NOxmode, the butterfly valve
moves to a smaller open position which has been adapted
to the pressure ratios.

BCU 560, BCU 565 · Edition 02.16 12
Application > Examples of application
1.1.6 PROFINET connection using bus module BCM
12 3
BCU 56x
BCM
BCU 56x
BCM
BCU 56x
BCM
PROFINET
L1
BUS
FCU P
HT
PLC
The bus system transfers the control signals from the auto-
mation system (PLC) to the BCU/BCM for starting, resetting,
controlling the air valve, purging the furnace or for cooling
and heating during operation. In the opposite direction, it
sends operating status, the level of the flame signal and the
current program status.
Control signals that are relevant for safety, such as the safety
interlocks, purge and HT input, are transferred independently
of the bus communication by separate cables.

BCU 560, BCU 565 · Edition 02.16 13
Application > Examples of application
1.1.7 ON/OFF rotary impulse control for
burners up to 360kW
For processes which require a turndown
of more than 10:1 and/or those which
require heavy circulation of the furnace
atmosphere to ensure a uniform tem-
perature, e.g. heat treatment furnaces
operating at low and medium tempera-
tures in the metallurgical industry.
With ON/OFF cyclic control, the capacity
supplied to the process is controlled by
means of a variable ratio of the operat-
ing time to the pause time. In this type of
control, the burner output pulse frequen-
cy always maintains full momentum and
results in maximum convection in the
furnace chamber, even with regulated
heating.
The pneumatic ratio control system con-
trols the gas pressure on the burner pro-
portionally to the air pressure and thus
maintains a constant air/gas ratio. At the
same time, it acts as a low air pressure
protection device.
The ignition and monitoring of the in-
dividual burners is ensured by burner
control unit BCU560.
The centrally checked safety functions
such as pre-purge, tightness test, flow
detector and pressure switch check
(gas
min.
, gas
max.
, air
min.
) are provided
by the FCU500.
M
PZL PZH PZ
PZL PDZ
TE
M
FCU 500..F0
µC P
DG DG DG
VAS VAS
VAS
VCG
VCG
VR..L
VR..L
DG DG
DGmin DG max
49 15 131450
45
47 4858
>750°
pu/2
ϑ1
46
2
3
DLmin DLPurge
BCU 560..F3
BCU 560..F3
STM

BCU 560, BCU 565 · Edition 02.16 14
Application > Examples of application
1.1.8 Modulating burner control
For processes that do not require heavy
circulation in the furnace, e.g. aluminium
smelting furnaces.
This system is suitable for processes in
which infiltrated air may flow into the
furnace through switched off burners.
The capacity can be adjusted continu-
ously by activating the control element
(analogue or 3-point step signal). The
pneumatic ratio control system controls
the gas pressure proportionally to the air
pressure and thus maintains a constant
air/gas ratio. At the same time, it acts
as a low air pressure protection device.
One burner control unit per burner is
required for ignition and monitoring.
The centrally checked safety functions
such as pre-purge, setting the valve
to ignition position via a butterfly valve
control system, tightness test, flow detec-
tor and pressure switch check (gasmin.,
gasmax., airmin.) are provided by the
FCU500.
FCU 500..F1
µC
P
DG DG DG
VAS VAS
VCG
VCG
DGmin DG max
49 15 131450
53
45
47 4858
pu/2
M
PZL PZH PZ
PZL PDZ
TE
BCU 560..F0
M
M
TC
90°➔0°
0°➔90°
54
55
VAS
DGDG
>750°
ϑ1
2
3
DLmin DLPurge
66
BCU 560..F0
66
16
57
STM

BCU 560, BCU 565 · Edition 02.16 15
2 Certification
Certified to SIL and PL
For systems up to SIL 3 pursuant to EN 61508 and PL e pursu-
ant to ISO 13849
EU certified pursuant to
– Gas Appliances Directive (2009/142/EC)
Meets the requirements of the
– Low Voltage Directive (2006/95/EC),
– EMC Directive (2004/108/EC).
FM approved
Factory Mutual Research Class: 7400 Process Control Valves.
Designed for applications pursuant to NFPA 85 and NFPA 86.
www.approvalguide.com
Eurasian Customs Union
The products BCU 560 and BCU 565 meet the technical speci-
fications of the Eurasian Customs Union.

BCU 560, BCU 565 · Edition 02.16 16
1 2 3 4645 65 66 67 6849 50 51
17 18 37 38
13 14 15
NL1
V1
V2
V3
max. 1 A;
24
V DC,
250 V AC
BCU 560..F3
3,15AT
µC
88
P70
P69
P70
P73
P72P72
c
ϑ
0 V+24 V
41 42
24V
DC
HT
pu
2GZL
PZL
P
5 6 9 11 1210762 61
A
P72P71
c
230V
2AT
53 54
IZ
0,6 × IN
3 Function
3.1 Connection diagram
3.1.1 BCU560..F3 with ionization control in double-
electrode operation
Alternative flame control, see page22 (Flame control).
Electrical connection, see page106 (Project planning infor-
mation)
Explanation of symbols, see page126 (Legend)

BCU 560, BCU 565 · Edition 02.16 17
1 2 3 4645 65 66 67 6849 50 51
17 18 37 38
13 14 15
NL1
V1
V2
V3
max. 1 A;
24
V DC,
250 V AC
BCU 560..F1
3,15AT
µC
88
P70
P69
P70
P73
P72P72
c
c
0 V+24 V
41 42
24V
DC
HT
pu
2GZL
PZL
5 6 9 11 1210762 61
ϑ
A
P72P71
230V
mA
(P40 = 2/3) => 51
52
53 54 55 56
P
IZ
0,6 × IN
Function > Connection diagram
3.1.2 BCU560..F1
Alternative flame control, see page22 (Flame control).
Detailed connection diagrams for actuators and frequency
converters, see from page78 (Capacity control)
Electrical connection, see page106 (Project planning infor-
mation)
Explanation of symbols, see page126 (Legend)

BCU 560, BCU 565 · Edition 02.16 18
1 2 3 4645 65 66 67 6849 50 51
17 18 37 38
13 14 15
NL1
V1
V2
V3
max. 1 A;
24 V DC,
250 V AC
BCU 560..F2
3,15AT
µC
88
P70P70
P73
P72P72
c
c
ϑ
0 V+24 V
41 42
24V
DC
HT
pu
2GZL
PZL
5 6 9 11 1210762 61
A
P72P71
230V
mA
(P69 = 13)
52
53 54 55 56
COM
HI
LO
AUTO
P
IZ
0,6 × IN
Function > Connection diagram
3.1.3 BCU560..F2
Alternative flame control, see page22 (Flame control).
Detailed connection diagrams for actuators and frequency
converters, see from page78 (Capacity control)
Electrical connection, see page106 (Project planning infor-
mation)
Explanation of symbols, see page126 (Legend)

BCU 560, BCU 565 · Edition 02.16 19
3.1.4 BCU565..F3 with ionization control in double-
electrode operation
Alternative flame control, see page22 (Flame control)
Electrical connection, see page106 (Project planning infor-
mation)
Explanation of symbols, see page126 (Legend)
Function > Connection diagram
1 2 3
17 18 37 38
13 14 15
5 6 9 11 1210
N
L1
V1
V2
V3
max. 1 A;
24 V DC,
250 V AC
BCU 565..F3
7
3,15AT
µC
88
c
62 61
0 V+24 V
41 42
24V
DC
53 54
ϑ
A
4645 4847 65 66 67 6849 50 51
P70P70
P73
P72P72
44
HT
pu
2GZL
PZL
P
PZL
PDZ
PZL
PDZ
P72P71
52
P69
2AT
c
IZ
Airmin Air
0.6 × IN

BCU 560, BCU 565 · Edition 02.16 20
3.1.5 BCU565..F1
Alternative flame control, see page22 (Flame control).
Detailed connection diagrams for actuators and frequency
converters, see from page78 (Capacity control)
Electrical connection, see page106 (Project planning infor-
mation)
Explanation of symbols, see page126 (Legend)
Function > Connection diagram
1 2 3 4645 4847 65 66 67 6849 50 51
17 18 37 38
13 14 15
5 6 9 11 1210
N
L1
V1
V2
V3
max. 1 A;
24 V DC,
250 V AC
BCU 565..F1
7
3,15AT
µC
88
P70P70
P73
P72P72
c
62 61
ϑ
0 V+24 V
41 42
24V
DC
44
HT
pu
2GZL
PZL
P
c
A
PZL
PDZ
PZL
PDZ
P72P71
mA
52
P69
(P40 = 2/3) => 51
53 54 55 56
IZ
Airmin Air
0.6 × IN