Kromschroder FCU 500, FCU 505 Technical Information

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Page 1

Protective system controls FCU 500, FCU 505

Technical Information · GB

6 Edition 02. 17

• For monitoring and controlling central safety functions in multiple burner systems on industrial furnaces

• Valve proving system for a valve system leak tightness check (optional)

• Safety temperature monitor (STM) or safety temperature limiter (STL) (optional)

• Long service life due to replaceable power module for fail-safe outputs

• Visualization and adaptation to the speciﬁc application via the PC programming and diagnostic software BCSoft to simplify logistics management

Page 2

Protective system controls FCU 500, FCU 505 ......1

Contents ............................................2

1 Application ........................................5

1.1 Application examples ..............................8

1.1.1 ON/OFF rotary impulse control .......................8

1.1.2 Modulating burner control ..........................10

1.1.3 Safety limits (LDS) for modulating burner control ...11

1.1.4 Flame control using the temperature ...............12

1.1.5 Furnace and zone control ...........................13

2 Certiﬁcation ......................................14

3 Function ..........................................15

3.1 Connection diagram ..............................15

3.1.1 FCU 500 .............................................15

3.1.2 FCU 505 .............................................16

3.1.3 Assignment of connection terminals ................17

3.2 Program sequence................................19

3.2.1 FCU 50 0..F0.........................................19

3.2.2 FCU 500..F1, FCU 50 0..F2..........................20

3.2.3 FCU 505..F1, FCU 505..F2 ...........................21

3.3 Animation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

4 Temperature monitoring......................... 23

4.1 High temperature operation with safety

temperature monitor function (STM function) .......24

4.1.1 With integrated STM ................................ 24

4.1.2 With external STM ...................................25

4.1.3 With integrated and external STM .................. 25

4.2 Maximum temperature monitoring with (ﬂue gas) safety temperature limiter (STL /FSTL

function) ..............................................26

4.2.1 With integrated STL/FSTL ..........................26

4.2.2 With external STL/FSTL ............................26

5 Air control ........................................27

5.1 Controlled air ﬂow ................................28

5.2 Capacity control ..................................29

6 Furnace zone control .............................31

7 Valve proving system ............................ 33

7.1 Tightness control..................................34

7.1.1 Test instant...........................................35

7.1.2 One test volume bet ween 2 gas solenoid valves ....36

7.1.3 One test volume for system tightness...............39

7.1.4 Two test volumes for system tightness .............. 42

7.1.5 Large test volumes with reduced testing time ......46

7.2 Test period tP ..................................... 48

7.2.1 For one test volume Vp1 between 2 gas solenoid

valves ......................................................48

7.2.2 For one test volume V

7.2.3 For two test volumes for system tightness (V V

) ........................................................49

7.2.4 Extended valve opening time 1 t

7.2.5 Measurement time t

for system tightness .......48

..................50

...............................53

7.3 Proof of closure function ..........................57

8 BCSoft........................................... 58

9 Fieldbus communication via Ethernet . . . . . . . . . . . 59

9.1 FCU and bus module BCM ...................... 60

9.2 Conﬁguration, planning ..........................61

9.2.1 Proﬁnet/Device master data ﬁle (GSD)..............61

9.2.2 Modbus TCP..........................................61

9.2.3 Modules/Registers for process data................62

9.2.4 Device parameters and statistics . . . . . . . . . . . . . . . . . . . 68

10 Program step/status ........................... 69

11 Fault signalling ................................. 70

12 Parameters ......................................74

12.1 Scanning the parameters........................79

12.2 Safety limits .....................................79

12.2.1 Emergency stop....................................79

12.2.2 High gas pressure protection ......................80

12.2.3 Low gas pressure protection.......................80

12.2.4 Low air pressure protection.........................81

FCU 500, FCU 505 · Edition 02.17 2

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12.2.5 Safet y time during operation tSB ...................81

12.3 High temperature operation.....................82

12.3.1 Temperature monitoring mode ....................82

12.3.2 Thermocouple......................................83

12.3.3 Temperature difference limit value ................83

12.3.4 STM limit value (high temperature operation).....84

12.3.5 STL /FSTL limit value (system protection).........84

12.3.6 Temperature hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

12.3.7 Pre-purge during high temperature operation ....86

12.4 Air control........................................87

12.4.1 Fan in the event of fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87

12.4.2 Fan run-up time t

12.4.3 Fan ready for operation .............................87

12.4.4 Air monitoring during controlled air ﬂow...........88

12.4.5 Pre-purge time t

12.4.6 Air ﬂow monitoring during pre-purge ..............89

12.4.7 Post-purge time t

12.4.8 Air ﬂow monitoring during post-purge.............90

12.4.9 Capacit y control.....................................91

12.4.10 Running time selection ..........................10 0

12.4.11 Running time ....................................100

12.4.12 Controller enable signal delay time t

12.4.13 Minimum enable time ...........................101

12.4.14 Burner operating signal..........................101

12.4.15 Controller enable time limit......................102

12.4.16 Capacity control (bus) ...........................103

................................87

.................................88

...............................89

.........101

12.5 Valve check ....................................108

12.5.1 Valve proving system..............................108

12.5.2 Relief valve (VPS) .................................108

12.5.3 Tightness control test volume ....................109

12.5.4 Pressure reduction V

12.5.5 Opening time relief valve V3 ......................110

12.5.6 Measurement time V

12.5.7 Measurement time V

12.5.8 Valve opening time 1 t

12.5.9 Valve opening time 2 t

...........................110

and Vp2 ..................110

..........................112

12.6 Behaviour during start-up .....................113

12.6.1 Minimum pause time tMP .........................113

12.6.2 Switch-on delay time t

12.6.3 Filling time before start-up .......................113

..........................113

12.7 Manual mode .................................. 114

12.7.1 Operating time in Manual mode ..................114

12.8 Functions of terminals 51, 65, 66, 67 and 68 . 115

12.8.1 Function of terminal 51 ...........................115

12.8.2 Function of terminal 65 ...........................116

12.8.3 Function of terminal 66 ...........................116

12.8.4 Function of terminal 67 ...........................117

12.8.5 Function of terminal 68 ...........................117

12.9 Password ......................................118

12.10 Fieldbus communication ....................118

13 Selection ......................................119

13.1 Type code ......................................119

14 Project planning information ..................120

14.1 Installation.....................................120

14.2 Commissioning ................................120

14.3 Electrical connection .......................... 121

14.3.1 OCU ...............................................121

14.3.2 Safety current inputs..............................122

14.4 High temperature operation...................123

14.4.1 Safety temperature monitor (STM) ...............123

14.4.2 Safety temperature limiter (STL)..................124

14.4.3 Temperature sensors (double thermocouples) . . .124

14.4.4 Thermocouples....................................124

14.4.5 PFH

and thermocouple........................................126

value for STM/STL temperature module

14.5 Safety interlock output ........................ 127

14.5.1 Safety interlock output in the case of higher

power requirement .......................................127

14.5.2 BCU with power supply for valves and ignition

transformer via safety interlocks.........................128

14.6 Actuators ......................................129

14.6.1 IC 20...............................................129

14.7 Air control ......................................129

14.8 Parameter chip card ...........................130

14.9 System leak tightness check ..................130

15 Accessories.................................... 131

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15.1 BCSoft ..........................................131

15.1.1 Opto-adapter PCO 200 ...........................131

15.1.2 Bluetooth adapter PCO 300 ......................131

15.2 OCU.............................................131

15.3 Connection plug set ...........................132

15.4 Stickers for labelling ...........................132

15.5 “Changed parameters” stickers................132

16 OCU ...........................................133

16.1 Application.....................................133

16. 2 Function .......................................134

16.2.1 Manual mode......................................135

16.3 Electrical connection ..........................135

16.4 Installation.....................................136

16.5 Selection.......................................136

16.6 Technical data for OCU . . . . . . . . . . . . . . . . . . . . . . . . 136

17 BCM 500 ...................................... 137

17.1 Application ......................................137

17. 2 F unction ........................................137

17.3 Electrical connection ...........................137

17.4 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

17. 5 S e l e c t ion .......................................138

17.6 Technical data..................................138

18 Technical data .................................139

18.1 Electrical data .................................139

18.2 Mechanical data...............................140

18.3 Environment ...................................140

18.4 FCU..H1........................................140

18.5 Dimensions ....................................140

18.6 Safety-speciﬁc characteristic values...........141

18.7 Converting units ...............................142

19 Maintenance ..................................143

20 Legend ........................................144

21 Glossary.......................................145

21.1 Safety shut-down.............................. 145

21.2 Fault lock-out..................................145

21.3 Warning signal.................................145

21.4 Timeout ........................................146

21.5 Lifting .........................................146

21.6 Diagnostic coverage DC.......................146

21.7 Operating mode ...............................146

21.8 Safe failure fraction SFF........................147

21.9 Probability of dangerous failure PFH

21.10 Mean time to dangerous failure MTTF

........147

.....147

Feedback .........................................148

Contact...........................................148

FCU 500, FCU 505 · Edition 02.17 4

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Application

▼

1 Application

FCU with plug-in connection terminals

Protective system control FCU 500 is designed to mon-

itor and control central safety functions, e.g. gas gas

max.

, air

, pre-purge, tightness test, high tempera-

min.

ture operation or start enable for burner control units, in multiple burner systems on industrial furnaces. In a furnace and zone control system, the FCU 500 assumes central functions. The FCU 505 is used to monitor local safety functions and to control the zone capacity. If the centrally checked safety requirements, e.g. pre-purge,

ﬂow detector and pressure switch check, have been

met, the FCUs issue the start enable signal to the burner control units.

The FCU is optionally available with integrated safety

temperature monitor or safety temperature limiter, integrated tightness control and with an interface for

min.

controlling the capacity of actuators or a frequency converter interface.

The program status and device parameters can be read

directly from the unit. The FCU can be activated manually using the integrated Manual mode for setting and diagnostic purposes.

Thanks to the optionally integrated valve proving sys-

tem, 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 the FCU 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 FCU to transfer the parameters, for example when replacing the unit.

FCU 500, FCU 505 · Edition 02.17 5

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Application

The monitored outputs for the actuator and valves are

accommodated in a plug-in power module. This can simply be replaced if necessary.

Once the plug-in power module has been removed, the param-

eter chip card and fuses are accessible.

The FCU can be installed on a DIN rail in the control

cabinet. Plug-in connection terminal strips on the FCU make it easier to install and remove.

The external operator-control unit OCU is available as

an option for the protective system controls. The OCU can be installed in the control cabinet door instead of standard control units. The program status, statistics, parameter values 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.

Thanks to the operator-control unit OCU, display functions and

operation of the FCU can be relocated to the control cabinet door.

The optional bus module BCM 500 makes it possible

to connect the FCU to a ﬁeldbus interface in a Proﬁnet or Modbus TCP network. Networking via the ﬁeldbus enables multiple FCUs to be controlled and monitored by an automation system (e.g. PLC). The bus module is prepared for DIN rail installation. It is pushed on to the FCU from the side.

The address for the ﬁeldbus communication is set using three

code switches.

FCU 500, FCU 505 · Edition 02.17 6

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Application

Roller hearth kiln in the ceramics industry

Shaft melting furnace Smelting and holding furnace

FCU 500, FCU 505 · Edition 02.17 7

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Application

PZL PZH PZ

DG DG DG

min

49 15 131450

FCU 500..F0

max

µC

STM

VAS

pu/2

>750°

47 4858

minDLPurge

PZL PDZ

DG DG

VAS

BCU 460..L

VCG

VR..L

VCG

VR..L

1.1 Application examples

1.1.1

ON/OFF ro tar y impul se contr ol

For processes which require a turndown of more than 10:1 and/or those which require heavy circula-

tion of the furnace atmosphere to ensure a uniform temperature, e.g. heat treatment furnaces operating at low and medium temperatures 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 operating time to the pause time. In this type of control, the burner output pulse frequency always maintains full momentum and results in maximum convection in the furnace chamber, even with regulated heating.

The pneumatic ratio control sys-

tem controls the gas pressure on the burner 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.

▼

FCU 500, FCU 505 · Edition 02.17 8

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Application

PZL PZH PZ

VAS

BCU 460..L

The ignition and monitoring of the

individual burners is ensured by burner control unit BCU 460..L.

The centrally checked safety func-

tions such as pre-purge, tightness

test, ﬂow detector and pressure switch check (gas air

) are provided by the FCU 500.

min.

, gas

max.

>750°

VAS

pu/2

VAS

VCG

VR..L

BCU 460..L

DG DG DG

min

49 15 131450

max

µC

FCU 500..F0

47 4858

STM

minDLPurge

PZL PDZ

DG DG

FCU 500, FCU 505 · Edition 02.17 9

VCG

VR..L

Page 10

Application

PZL PZH PZ

DG DG DG

min

49 15 131450

FCU 500..F1

µC

STM

minDLPurge

VAS

max

>750°

0°➔90°

90°➔0°

54 55

47 4858

PZL PDZ

DGDG

pu/2

1.1.2 Modulating burner control

For processes that do not require heavy circulation in the furnace, e.g. aluminium smelting furnaces.

This system is suitable for process-

VAS

BCU 460..L

es in which inﬁltrated air may ﬂow into the furnace through switched off burners. The capacity can be adjusted continuously by activating the air control valve (analogue or

VAS

VCG

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

BCU 460..L

time, it acts as a low air pressure protection device.

One burner control unit per burner is required for ignition and monitor-

VCG

ing.

The centrally checked safety func-

tions such as pre-purge, setting the

valve to ignition position via a butterﬂy valve control system, tightness test, ﬂow detector and pressure switch check (gas air

) are provided by the FCU 500.

min.

, gas

max.

FCU 500, FCU 505 · Edition 02.17 10

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Application

PZL PZH PZ

DG DG DG

min

49 15 131450

FCU 500..F1

µC

STM

minDLPurge

VAS

max

>750°

0°➔90°

90°➔0°

47 4858

PZL PDZ

DGDG

pu/2

1.1.3 Safety limits (LDS) for modulating burner control

The centrally checked safety func-

tions such as pre-purge, setting the valve to ignition position via a but-

VAS

BCU 560..F0

terﬂy valve control system, tightness test, ﬂow detector and pressure switch check (gas air

) are provided by the FCU 500.

min.

, gas

max.

The capacity can be adjusted con-

VAS

VCG

tinuously by activating the control element (analogue or 3-point step signal).

To ensure that the correct air vol-

ume is available for ignition (start

BCU 560..F0

fuel ﬂow rate) when starting the burners, the FCU sends the burner start enable signal to the BCUs via the “LDS (limits during start-up)” output.

VCG

The circuit design of the safety

interlock and LDS outputs on the FCU and the corresponding in-

puts on the BCUs ensures that the burners can only start if the safety interlocks and the LDS output have enabled burner start-up.

FCU 500, FCU 505 · Edition 02.17 11

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Application

1.1.4 Flame control using the temperature

FCU 500..H1

5-8

STM

BCU 56x..D

µC

BCU 56x..D

µC

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 temperature mode (HT). When the HT input is activated, the burner control units switch to High temperature mode. They operate without evaluation of the ﬂame signal and their internal ﬂame control system 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 active signal at the HT inputs of the burner control units. The ﬂame signals are monitored once again by the UV sensor or ﬂame rod.

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.

FCU 500, FCU 505 · Edition 02.17 12

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Application

PZL PZH PZ

FCU 505..F1

+24V

49 15 131450

FCU 500..F0

µC

4758 48

PZL PDZ

1.1.5 Furnace and zone control

The FCU 500 (furnace FCU) performs central tasks

such as checking the safety interlocks, fan control, system leak tightness check and pre-purge.

It signals to the FCU 505 in the zones that the butterﬂy valves can be moved to the purge position. Signals are

µC

54 55

BCU

+24V

BCU

FCU 505..F1

µC

54 55

sent to the butterﬂy valves by the FCU 505. The butterﬂy valves move into position. A signal is sent to the FCU 505 via their safety interlock input that the central FCU 500 has issued the enable signal for the burners.

FCU 500, FCU 505 · Edition 02.17 13

Page 14

Certiﬁcation

2 Certiﬁcation

Certiﬁcates – see Docuthek.

Certiﬁed pursuant to SIL

For systems up to SIL 3 pursuant to EN 61508.

Pursuant to EN ISO 138491:2006, Table 4, the FCU

can be used up to PL e.

EU certiﬁed pursuant to

– Gas Appliances Directive (2009/142/EC) in conjunc-

tion with EN 298, EN 1643

Meets the requirements of the

– Low Voltage Directive (2006/95/EC),

– EMC Directive (2004/108/EC).

FM approved

ANSI/CSA approved

American National Standards Institute/Canadian

Standards Association –ANSI Z21.20/CSA C22.2, No. 199 www.csagroup.org –Class number: 333501 (natural gas, propane), 333581 (natural gas, LPG).

Eurasian Customs Union

The product FCU 500 meets the technical speciﬁca-

tions of the Eurasian Customs Union.

Factory Mutual Research Class: 7610 “Combustion Safe-

guards and Flame Sensing Systems”. Suitable for applications pursuant to NFPA 86. www.approvalguide.com

FCU 500, FCU 505 · Edition 02.17 14

Page 15

Function

3 Function

3.1 Connection diagram

3.1.1 FCU 500

Detailed connection diagrams for actuators and fre-

quency converters, see from page 91 (Capacity control)

PZL

Air

min

PZL

GZL

PZH

Gas

Air

PDZ

Gas

P72

PDZ

min

PZL

max

Electrical connection, see page 120 (Project planning information)

Explanation of symbols, see page 144 (Legend)

1 2 3 46 47 48 49 50 4 67 52 45 51 65 66 68

62 61 5 6 7 8 11

STM/

STL

+ - + -

24V

3,15AT

41 4216

17 18 57

13 14 1553

× 0.6

LDS

k11 k21

µC

FCU 505

FCU 500

5AT

54 55 56

0 V

+24 V

0.6 × I

P69

P70

P71

P73

FCU 500, FCU 505 · Edition 02.17 15

Page 16

Function

3.1.2 FCU 505

Detailed connection diagrams for actuators and fre-

quency converters, see from page 91 (Capacity control)

Electrical connection, see page 120 (Project planning

information)

Explanation of symbols, see page 144 (Legend)

+24 V

PZH

0.6 × I

Gas

STM/

STL

1 2 3 46 47 48 49 50 4 67 52 45 51 65 66 68

62 61 5 6 7 8 11

PZL

Air

PDZ

Gas

P72

PDZ

min

PZL

max

min

+ - + -

24V

3,15AT

41 4216

17 18 57

13 14 1553

PZL

GZL

P69

P70

P71

P73

µC

FCU 505

54 55 56

× 0.6

LDS

k11 k21

0 V

FCU 500, FCU 505 · Edition 02.17 16

Page 17

Function

3.1.3 Assignment of connection terminals

Terminal Type Designation Function

2 Controlled air ﬂow

24 V DC input

3 Remote reset Input for ex ternal signal (button) to reset the unit after a fault lock-out

4 Operating signal

5, 6 and 7, 8

11, 12 V AC input Supply voltage

13 14 Gas valve V2 Connection of phase for gas valve V2

15 Gas valve V3 Connection of phase for gas valve V3

57 Safety interlocks (limits) Safety enable signal to the burner control units

16 Safety limits (limits during start-up)

17 Purge Signal to FCU 505 or burner control units to inform them that purge is in process 18 High temperature operation Enable signal from the FCU indicating that the furnace system is in High temperature mode 41 42 Operating signal Operation signalling output, 24 V DC, max. 0.1 A 44 24 V DC input Fan ready for operation Feedback signal from fan indicating readiness for operation, see Parameter 31

Double

thermocouple

Safety circuit output

24 V DC output

Start-up signal Signal applied: FCU start; no signal: FCU stop

Signal applied: fan is started to supply air to the combustion chamber for cooling, for example. Only functional in standby. The function is deactivated as soon as a signal is received at terminal 1 (FCU start).

Signal from the burner control units to inform the FCU that a sufﬁcient number of burners is available for temperature control

Safety temperature monitor and/or safety temperature limiter

Gas valve V1 Connection of phase for gas valve V1

Fault Fault signalling output, 24 V DC, max. 0.1 A

Monitor the spontaneous ignition temperature of the gas/air mixture in High temperature mode and/or the maximum furnace or ﬂue gas temperature using the integrated temperature module of the FCU..H1

Voltage to operate the FCU, 11 = phase (L1), 12 = neutral conductor (N)

To ensure that the correct air volume is available for ignition (start fuel ﬂow rate) when starting the burners, the FCU sends the burner start enable signal to the burner control units via this output.

▼

FCU 500, FCU 505 · Edition 02.17 17

Page 18

Function

Terminal Type Designation Function

46 Controller enable/emergency stop

47 Minimum air pressure

48 Minimum air ﬂow

49 Minimum gas pressure Connection for pressure switch to monitor the minimum gas pres sure, see Parameter 13 50 Maximum gas pressure Connection for pressure switch to monitor the maximum gas pressure, see Parameter 12 51, 65,

66, 67, 68

53, 54, 55, 56

58 Fan

Safety circuit input

V AC output

Valve proving system

Programmable inputs

Feedback from actuator/frequency converter

Capacity control

Connection for the sensor of the valve proving system (tightness control pressure switch or POC switch for checking the closed position).

Connection for higher-level safety devices and interlocks (e.g. emergency stop, safety temperature monitor), see Parameter 10

Connection for pressure switch to monitor the minimum air pressure, see Parameter 15

Connection for a sensor to monitor the minimum air ﬂow during pre-purge or post-purge, see Parameters 35, 38

The terminals can be assigned a function using parameters. To do so, logical AND gatings with terminals 46, 47, 48, 49 or 50 are possible.

Connection for the position feedback signal from the actuator/frequency converter

Connection for capacity control using an actuator or frequency converter, see Parameter 40 to 47

Connection for fan control. Alternatively, this output can be used to activate a valve to check the function of the air pres sure switch.

FCU 500, FCU 505 · Edition 02.17 18

Page 19

Function

3.2 Program sequence

3.2.1 FCU 500..F0

Example of application, see page 8 (ON/OFF rotary

impulse control)

Switch on the FCU

▼

In the event of fault signal: reset

▼

Switch-on delay time t

Enable signal to burner control units for the burner start via the “safety

Start-up position/standby

▼

Start-up with ϑ signal

▼

running (parameter 63)

Safety interlocks check

Fan run-up time tGV running (parameter 30)

Pre-purge time tPV running (parameter 34)

Tightne ss test (if equipped with TC)

Gas enable via valves V1 and V2

▼

Pre-purge starts

▼

Air ﬂow monitoring

▼

interlock” output

▼

Operation

FCU 500, FCU 505 · Edition 02.17 19

Page 20

Function

3.2.2 FCU 500..F1, FCU 500..F2

Example of application, see page 10 (Modulating

burner control)

Switch on the FCU

▼

In the event of fault signal: reset

▼

Switch-on delay time t

Actuator moves to the position for maximum capacity

Actuator moves to the position for ignition capacity

Enable signal to burner control units for the burner start via the

Controller enabler signal delay time t

Start-up position/standby

▼

Start-up with ϑ signal

▼

running (parameter 63)

Safety interlocks check

▼

Fan run-up time t

running (parameter 30)

Pre-purge starts

▼

Air ﬂow monitoring

▼

Pre-purge time t

Tightne ss test (if equipped with TC)

running (parameter 34)

▼

Gas enable via valves V1 and V2

“safety interlock” output

▼

Operation/controller enable

running

FCU 500, FCU 505 · Edition 02.17 20

Page 21

Function

3.2.3 FCU 505..F1, FCU 505..F2

Example of application, see page 13 (Furnace and zone control)

Switch on the FCU

▼

In the event of fault signal: reset

▼

Switch-on delay time t

Actuator moves to the position for maximum capacity

Actuator moves to the position for ignition capacity

Controller enabler signal delay time t

Start-up position/standby

▼

Start-up with ϑ signal

▼

running (parameter 63)

Safety interlocks check

▼

Fan run-up time t

running (parameter 30)

Pre-purge starts

▼

FCU 500 pre-purge time t

Tightne ss test (if equipped with TC)

▼

Operation/controller enable

running

FCU 500, FCU 505 · Edition 02.17 21

Page 22

Function

3.3 Animation

The interactive animation shows the function of the

protective system control FCU 500.

Click on the picture. The animation can be controlled using the control bar at the bottom of the window (as on a DVD player).

To play the animation, you will need Adobe Reader 9 or a

FCU 500, FCU 505 · Edition 02.17 22

newer version. If you do not have Adobe Reader on your system, you can download it from the Internet. Go to ww w.adobe.com, click on “Adobe Reader” at the bottom of the page and follow the instructions.

If the animation does not start to play, you can download it from the document library (www.docuthek.com) as an independent application.

Page 23

Temperature monitoring

4 Temperature monitoring

The FCU..H1 is ﬁtted with an integrated temperature

module.

This module can be used as a safety temperature moni-

tor (STM) to monitor the spontaneous ignition temperature of the gas/air mixture or as a safety temperature limiter (STL) to monitor the maximum furnace/ﬂue gas temperature. Double thermocouples are connected to the temperature module to measure the temperature.

The functions STM and STL can also be combined. In

this case, the connected double thermocouple must reliably detect whether the spontaneous ignition temperature (> 750°C) has been exceeded and also whether the maximum permitted furnace temperature has been exceeded.

The safety temperature monitor and safety temperature

limiter functions can be adjusted to the requirements of the system using parameters 20, 22, 23, 24 and 25, see page 82 (High temperature operation).

FCU 500, FCU 505 · Edition 02.17 23

Page 24

Temperature monitoring

4.1 High temperature operation with safety

temperature monitor function (STM function)

As soon as the temperature in the furnace chamber

is above the spontaneous ignition temperature of the gas/air mixture (> 750°C), the FCU signals to the downstream burner control units via the fail-safe HT output that the furnace system is in High temperature 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. As soon as the signal to the HT inputs of the burner control units is no longer present, the ﬂame signals are once again monitored by a UV sensor or ﬂame rod.

Either the temperature module integrated in the FCU.. H1 or an external safety temperature monitor (STM)

can be used for High temperature mode. Pre-purge can be disabled for both versions in High temperature mode, see page 86 (Pre-purge during high temperature operation).

4.1.1 With integrated STM

The integrated temperature module (STM) can be used

for high temperature operation. Pre-purge can be disabled in High temperature mode, see page 86 (Prepurge during high temperature operation).

FCU 50x..H1

5-8

STM

BCU 4xx..D

µC

BCU 4xx..D

µC

FCU 500, FCU 505 · Edition 02.17 24

Page 25

Temperature monitoring

BCU 4xx..D

µC

BCU 4xx..D

µC

4.1.2 With external STM

An external safety temperature monitor (STM) can be

used for high temperature operation. Pre-purge can be disabled in High temperature mode, see page 86 (Pre-purge during high temperature operation).

FCU 50x..H0

FCU 50x..H1

BCU 4xx..D

µC

BCU 4xx..D

µC

STM

4.1.3 With integrated and external STM

The integrated temperature module can also be used in

conjunction with an external safety temperature monitor (STM). The spontaneous ignition temperature can then be monitored at two different points in the furnace.

FCU 50x..H1

5-8

STM

FCU 500, FCU 505 · Edition 02.17 25

Page 26

Temperature monitoring

4.2 Maximum temperature monitoring with (ﬂue gas) safety temperature limiter (STL/FSTL

function)

As soon as the maximum permitted temperature limit

is reached in the furnace or in the ﬂue gas or an error occurs on the monitoring equipment within the permitted temperature range (e.g. sensor discontinuity, sensor short-circuit), the FCU will perform a fault lock-out. The safety interlock output will no longer be set.

The temperature module integrated in the FCU..H1 or

an external safety temperature limiter (STL) can be used for this function.

4.2.1 With integrated STL/FSTL

FCU 50x..H1

5-8

STL

BCU 4xx..D

4.2.2 With external STL/FSTL

FCU 50x..H0 FCU 50x..H1

BCU 4xx..D

STL

BCU 4xx..D

FCU 500, FCU 505 · Edition 02.17 26

Page 27

Air control

PZL PZH PZ

PZL PDZ

BCU 580..F3

FCU 500..F0

µC

DG DG DG

VAS

VAGVAS

VAS

VR..L

DG DG

minDGmax

49 15 131450

47 4858

>750°

pu/2

minDLPurge

BCU 580..F3

VAGVAS

VAS

5 Air control

Acting as the furnace protective system, the FCU 500

assumes the task of central air control on a furnace. It controls and monitors the required air volume for startup, during operation and after the furnace has been shut down. The fan is activated by the FCU for this purpose. The static air pressure and the air volume for prepurge can be monitored by pressure switches.

VAS

BCU 580..F3

49 15 131450

FCU 500..F0

µC

>750°

47 4858

STM

minDLPurge

PZL PDZ

DG DG

VR..L

BCU 580..F3

VR..L

The capacity control function provided by the FCU 500..

F1/F2 and FCU 505..F1/F2 allows an additional central actuator or a frequency-controlled fan to be controlled and monitored. While the furnace is starting up, the capacity control system controls and monitors the required air volumes for purging and for starting the burners. During operation, the FCU enables the external temperature control system for capacity control.

FCU 500, FCU 505 · Edition 02.17 27

Page 28

Air control

PZL

Air

min

PZL

GZL

P71

P73

+24 V

PZH

0.6 × I

Gas

Air

PDZ

Gas

P69

P72

PDZ

min

P70

PZL

max

5.1 Controlled air ﬂow

On FCU 500, actuation of the input at terminal 2 acti-

vates the controlled air ﬂow function. The fan (terminal 58) is started in standby (with no start-up signal).

Air is fed to the combustion chamber, e.g. for cooling.

1 2 3 46 47 48 49 50 4 67 52 45 51 65 66 68

62 61 5 6 7 8 11

STM/

STL

+ - + -

24V DC

µC

FCU 505

FCU 500

5AT

3,15AT

41 4216

17 18 57

13 14 1553

54 55 56

× 0.6

LDS

k11 k21

The FCU starts the fan depending on the functions

deﬁned using parameters, see also page 81 (Low air pressure protection), page 88 (Air monitoring during controlled air ﬂow) and page 89 (Air ﬂow monitoring during pre-purge).

The controlled air ﬂow function is no longer performed

once the start-up signal has been received at terminal 1.

0 V

FCU 500, FCU 505 · Edition 02.17 28

Page 29

Air control

µC

5455

(

)

▼

5.2 Capacity control

As soon as a start-up signal has been received by the FCU..F1/F2 (terminal 1), the fan of an FCU 500..F1/F2

is started via terminal 58 after the switch-on delay time has elapsed. The air volume for pre-purge is requested via the outputs for central capacity control (terminals 53 to 56). Air ﬂow monitoring (terminal 48) starts. The pre-purge time starts if there is adequate air ﬂow.

After the elapse of the pre-purge time, the air volume for ignition is requested. After the program has ended

(limits during start-up, pre-purge and also tightness test for FCU..C1), the gas enable signal is issued via the valve outputs V1 (terminal 13) and V2 (terminal 14) and the burner start enable signal is issued to the burner control units via the “safety interlock” output (terminal 57).

The correct air volume for ignition (start fuel ﬂow rate)

must be available for each burner start, restart or startup attempt. To this end, the FCU sends the burner start enable signal to the BCUs via the “LDS (limits during start-up)” output.

A corresponding circuit design between the FCU and

the BCUs ensures that the burners can only start if the safety interlocks and the LDS output are active.

BCU..F0

+24

FCU 500..F1

FCU 500, FCU 505 · Edition 02.17 29

Page 30

Air control

µC

5455

(

)

After the burner operating signal from the burner con-

trol units has been received, the FCU enables the control system for operation. For pertinent parameter settings, see page 101 (Burner operating signal).

BCU..F0

+24

+24V

FCU 500..F1

54 55

Depending on parameter 40, actuators IC 20 and IC 40,

an actuator with an RBW interface or a fan controlled by a frequency converter can be actuated via the outputs for central capacity control, see page 91 (Capacity control).

FCU 500, FCU 505 · Edition 02.17 30

Page 31

Furnace zone control

▼

PZL PZH PZ

FCU 505..F1

+24V

49 15 131450

FCU 500..F0

µC

4758 48

PZL PDZ

6 Furnace zone control

For furnace zone control, one FCU 500 is used to

control the furnace and several FCU 505 are used to control the individual modulating zones (FCU 505..F1 or FCU 505..F2). When connecting several FCUs in a circuit, a hierarchical operating structure is applied.

µC

54 55

BCU

FCU 505..F1

µC

54 55

BCU

+24V

BCU

The furnace FCU (FCU 500) performs central tasks

such as checking the central safety functions, fan control, system leak tightness check and pre-purge.

FCU 500, FCU 505 · Edition 02.17 31

Page 32

Furnace zone control

The zone FCUs (FCU 505) control the zone capacity.

After checking the safety interlocks (after expiry of the

switch-on delay time) and when the fan run-up time is started, the furnace FCU signals to the zone FCUs via the input at terminal 66 that they should move the actuators to purge position. After the purge (and the tightness test if applicable) has been ended, the

furnace FCU signals to the zone FCUs via the input at

terminal 46 that burner start is enabled. When they receive this signal, the zone FCUs move the valves to ignition position for starting the burners and then issue the enable signal to the burner control units to start the burners.

FCU 500, FCU 505 · Edition 02.17 32

Page 33

Valve proving system

7 Valve proving system

The FCU..C1 is ﬁtted with an integrated valve proving

system. This allows the tightness of two or more gas solenoid valves and the pipework to be checked, see page 34 (Tightness control). Alternatively, the closed position of a gas solenoid valve can be checked using a

POC switch, see page 57 (Proof of closure function).

Once the test has been carried out successfully, the furnace is enabled for start-up.

The tightness control function satisﬁes the require-

ments of EN 1643 (Valve proving systems for automatic shut-off valves for gas burners and gas appliances).

By checking the closed position using the proof of clo-

sure function, the FCU complies with the requirements of NFPA 85 (Boiler and Combustion Systems Hazards

Code) and NFPA 86 (Standard for Ovens and Furnaces).

FCU 500, FCU 505 · Edition 02.17 33

Page 34

Valve proving system

7.1 Tightness control

The aim of the tightness control is to identify an in-

admissible leak on one of the gas solenoid valves and to prevent burner start. European standards

EN 7462 and EN 676 stipulate tightness controls for

capacities over 1200 kW (NFPA 86: from 117 kW or

400,000 Btu/h).

The FCU offers several ways of testing tightness:

1. Between 2 gas solenoid valves with one test volume (parameter 53 = 1):

2. The system tightness of a complete gas inlet section with one test volume and pressure reduction using a relief valve (parameter 53 = 2):

3. The system tightness of a complete gas inlet section with two test volumes and pressure reduction using a relief valve (parameter 53 = 3):

The valves and the pipework between the valves are

tested.

FCU 500, FCU 505 · Edition 02.17 34

Page 35

Valve proving system

7.1.1 Test instant

Depending on the parameter setting, the tightness

control checks the tightness of the pipework and the gas solenoid valves before each start-up and/or after each shut-down of a furnace system, see page 108 (Valve proving system).

The gas line is always safeguarded by a gas solenoid

valve during this check.

Before furnace start-up

P1HO00 H7 H8

TC Test

57 42

PVtRF

The FCU starts testing the tightness of the gas solenoid

valves and pipework between the valves parallel to the pre-purge time. The gas line is always safeguarded by a gas solenoid valve during this check. When pre-purge is ﬁnished and the tightness has been checked successfully, the safety valves for operating the system are opened after the safety interlocks have been enabled.

After furnace shut-down

08 00

TC Test

57 42

After the furnace has been shut down, the FCU starts

testing the tightness of the gas solenoid valves and pipework between the valves. After the tightness has been checked successfully, the next furnace start is enabled as regards the tightness criteria.

Each time the FCU is reset or connected to mains voltage, a tightness test is performed immediately. The testing time can be reduced for large volumes, see page 111 (Large test volumes).

FCU 500, FCU 505 · Edition 02.17 35

Page 36

Valve proving system

PZL

PZH

4913

▼

7.1.2 One test volume between 2 gas solenoid valves

V1 V2

450

pu/2

The tightness control checks the tightness of the test

volume Vp1 between gas solenoid valves V1 and V2.

FCU 500, FCU 505 · Edition 02.17 36

Page 37

Valve proving system

▼

Program A Program B

tL = P59

tM = P56

pZ >

tL = P59

tM = P56

pZ >

–

V1 V2

START

pZ >

pu/2

Program sequence

The tightness test starts by checking the external pres-

sure switch. If pressure pZ > pu/2, program A starts.

–

tL = P59

tM = P56

If pressure p (Program B).

Program A

Valve V1 opens for the opening time t

eter 59. V1 closes again. During the measurement time tM, the tightness control checks the pressure pZ between the valves.

If pressure p

< pu/2, program B starts, see page 38

set in param-

is less than half the inlet pressure pu/2,

valve V2 is leaking.

pZ >

tL = P59

–

If pressure p

is greater than half the inlet

pressure pu/2, valve V2 is tight. Valve V2 is opened for the set opening time tL. V2 closes again.

During the measurement time t

, the tightness control

checks the pressure pZ between the valves.

If pressure p

is greater than half the inlet

pressure pu/2, valve V1 is leaking.

tM = P56

–

pZ >

If pressure p

is less than half the inlet pressure pu/2,

valve V1 is tight.

The tightness test can only be performed if pressure p

downstream of V2 is around atmospheric pressure.

FCU 500, FCU 505 · Edition 02.17 37

Page 38

Valve proving system

Program A Program B

tL = P59

tM = P56

pZ >

–

V1 V2

START

pZ >

pu/2

Program B

Valve V2 opens for the set opening time tL. V2 closes

again. During the measurement time tM, the tightness control checks the pressure pZ between the valves.

–

If pressure p

> pu/2, valve V1 is leaking.

< pu/2, valve V1 is tight. Valve V1 is

opened for the set opening time tL. V1 closes again.

tL = P59

tM = P56

pZ >

–

During the measurement time t

, the tightness control

checks the pressure pZ between the valves.

If pressure p

< pu/2, valve V2 is leaking.

> pu/2, valve V2 is tight.

The tightness test can only be performed if pressure p

downstream of V2 is around atmospheric pressure.

tL = P59

tM = P56

pZ >

–

FCU 500, FCU 505 · Edition 02.17 38

tL = P59

tM = P56

–

pZ >

Page 39

Valve proving system

LZH

▼

7.1.3 One test volume for system tightness

450

22pu/2

The tightness control checks the system tightness

of the test volume Vp1 between the central shut-off valve V1, relief valve V3 and the burner valves. The opening times of the relief valve V3 and the shut-off valve V1 are identical.

FCU 500, FCU 505 · Edition 02.17 39

Page 40

Valve proving system

▼

Program A Program B

tL = P59

tM = P56

tL = P59

tM = P56

–

pu/2

START

Program sequence

The tightness test starts by checking the external pres-

sure switch. If pressure pZ > pu/2, program A starts. If pressure pZ < pu/2, program B starts, see page 41

–

tL = P59

tM = P56

(Program B).

Program A

Valve V1 opens for the opening time t

set in param-

eter 59. V1 closes again. During the measurement time tM, the tightness control checks the pressure pZ between the valves.

If pressure p

is less than half the inlet pressure pu/2,

test volume Vp1 is leaking.

tL = P59

–

If pressure p

is greater than half the inlet

pressure pu/2, test volume Vp1 is tight. Valve V3 is opened for the set opening time tL. V3 closes again.

During the measurement time t

, the tightness control

checks the pressure pZ between the valves.

If pressure p

is greater than half the inlet

pressure pu/2, valve V1 is leaking.

If pressure p

is less than half the inlet pressure pu/2,

valve V1 is tight.

tM = P56

–

The tightness test can only be performed if pressure p

downstream of V3 is around atmospheric pressure.

FCU 500, FCU 505 · Edition 02.17 40

Page 41

Valve proving system

Program A Program B

tL = P59

tM = P56

–

pu/2

START

Program B

Valve V3 opens for the set opening time tL. V3 closes

again. During the measurement time tM, the tightness control checks the pressure pZ between the valves.

If pressure p

> pu/2, valve V1 is leaking.

< pu/2, valve V1 is tight. Valve V1 is

–

opened for the set opening time tL. V1 closes again.

tL = P59

tM = P56

–

During the measurement time t

, the tightness control

checks the pressure pZ between the valves.

If pressure p

> pu/2, test volume Vp1 is tight.

< pu/2, test volume Vp1 is leaking.

The tightness test can only be performed if pressure p

downstream of V3 is around atmospheric pressure.

tL = P59

tM = P56

–

FCU 500, FCU 505 · Edition 02.17 41

tL = P59

tM = P56

–

Page 42

Valve proving system

>750°

▼

7.1.4 Two test volumes for system tightness

START

Vent V

Program A Program B

tL3 = P55

pZ >

–

V1 V2

450

pu/2

The test volumes Vp1 and Vp2 (gas solenoid valves V1

and V2, relief valve V3, the burner valves and the pipework) are checked to test the system tightness of the entire gas inlet section.

Program sequence

At the start of the tightness test, the relief valve V3 is

opened to reduce the pressure of the test volume V

to around atmospheric pressure. The opening time for

V3 can be deﬁned using parameter 55, see page 110

(Opening time relief valve V3). The tightness control queries the pressure pZ using the external pressure switch to check the ﬁrst test volume. If pressure pZ > pu/2, program A starts, see page 43 (Program A). If pressure pZ < pu/2, program B starts, see page 44 (Program B).

FCU 500, FCU 505 · Edition 02.17 42

Page 43

Valve proving system

tL3 = P55

Vent V

START

▼

Program A Program B

tL = P59

pZ >

–

tL = P59

Test of valve 1

tM = P56

pZ >

–

tM = P56

pZ >

tL = P59

tM = P56

Program A Program B

Test of valve 2

tL = P59

tM = P56

Program A

Valve V1 opens for the opening time tL set in param-

eter 59. Valve V1 closes again. During the measurement time tM set in parameter 56, the tightness control checks the pressure pZ between the valves V1 and V2.

If pressure p

Valve V2 opens for the opening time t

< pu/2, valve V2 is leaking.

> pu/2, valve V2 is tight.

set in param-

eter 59. V2 closes again. During the measurement time tM, the tightness control checks the pressure pZ

–

between the valves.

If pressure p

The test volume V

> pu/2, valve V1 is leaking.

< pu/2, valve V1 is tight.

has been successfully checked for

tightness.

For checking the second test volume, see page 45 (Checking the ﬁrst and second test volumes (V

+ Vp2)).

pZ >

–

FCU 500, FCU 505 · Edition 02.17 43

–

pZ >

Page 44

Valve proving system

tL3 = P55

Vent V

START

▼

Program A Program B

tL = P59

pZ >

–

tL = P59

Test of valve 1

tM = P56

pZ >

–

tM = P56

pZ >

tL = P59

tM = P56

Program A Program B

Test of valve 2

tL = P59

tM = P56

Program B

Valve V2 opens for the opening time tL set in param-

eter 59. Valve V2 closes again. During the measurement time tM set in parameter 56, the tightness control checks the pressure pZ between the valves V1 and V2.

If the pressure p

Valve V1 opens for the opening time t

< pu/2, valve V1 is leaking.

> pu/2, valve V1 is tight.

set in param-

eter 59. V1 closes again. During the measurement time tM, the tightness control checks the pressure pZ

–

between the valves.

If pressure p

The test volume V

> pu/2, valve V2 is tight.

< pu/2, valve V2 is leaking.

has been successfully checked for

tightness.

For checking the second test volume, see page 45 (Checking the ﬁrst and second test volumes (V

+ Vp2)).

pZ >

–

FCU 500, FCU 505 · Edition 02.17 44

–

pZ >

Page 45

tL = P59

tM = P56

–

tL = P59

tM = P56

pZ >

–

pZ >

–

pZ >

–

tM = P56

Program A Program B

Test of valve 2

Valve proving system

Test of valve V3

and

burner-side

valves

+ V

Wait for 1 s

tL = P59

tM = P57

pZ >

END

V2V3

Checking the ﬁrst and second test volumes (Vp1 + Vp2)

To check the test volume Vp2, relief valve V3 is closed

and valve V2 is opened. The two test volumes Vp1 and

Vp2 are connected to each other. After a waiting time

of 1 s, valve V1 opens for the opening time tL set in parameter 59. Valve V1 then closes and the measurement time set in parameter 57 starts to elapse, see page 110 (Measurement time Vp1 and Vp2). After the measurement time has elapsed, the tightness control

–

checks pressure pZ. If pZ < pu/2, the test volume Vp2 is leaking (relief valve V3, the burner valves or the pipework are leaking). If pZ > pu/2, test volume Vp2 has been successfully checked for tightness.

Valves V1, V2 and V3, the burner valves and the pipe-

work are tight.

FCU 500, FCU 505 · Edition 02.17 45

Page 46

Valve proving system

LZH

▼

7.1.5 Large test volumes with reduced testing time

The testing time for the tightness test can be reduced

for a large test volume. Two pressure switches are re-

quired for this, see page 111 (Large test volumes).

The ﬁrst pressure switch is set to ¼ of the inlet pres-

sure pu, the second one to ¾ of the inlet pressure.

Parameter 70 must be set to 1 for this purpose, see

page 116 (Function of terminal 65).

Program sequence

The tightness control queries the pressure pZ using

the ﬁrst pressure switch (pu/4). If pressure pZ > pu/4, program A starts, see page 47 (Program A (reduced testing time)). If pressure pZ < pu/4, program B starts, see page 47 (Program B (reduced testing time)).

V1 V2

450

45 65

PZ PZ

pu/4

3pu/4

FCU 500, FCU 505 · Edition 02.17 46

Page 47

Valve proving system

Program A Program B

tL = P59

tM = P56

pZ >

tL = P59

tM = P56

pZ >

–

V1 V2

START

pZ >

PZ PZ

3pu/4pu/4

Program A (reduced testing time)

Valve V1 opens for the opening time tL set in param-

eter 59. V1 closes again. During the measurement time tM, the tightness control checks the pressure pZ

–

tL = P59

between the valves.

If pressure p

< 3pu/4, valve V2 is leaking.

> 3pu/4, valve V2 is tight. Valve V2 is

opened for the set opening time tL. V2 closes again.

During the measurement time t

, the tightness control

checks the pressure pZ between the valves.

tM = P56

pZ >

–

If pressure p

< pu/4, valve V1 is tight.

> pu/4, valve V1 is leaking.

Program B (reduced testing time)

Valve V2 opens for the opening time t

set in param-

eter 59. V2 closes again. During the measurement time tM, the tightness control checks the pressure pZ between the valves.

tL = P59

tM = P56

If pressure p

> pu/4, valve V1 is leaking.

< pu/4, valve V1 is tight. Valve V1 is

opened for the set opening time tL. V1 closes again.

During the measurement time t

, the tightness control

checks the pressure pZ between the valves.

–

pZ >

If pressure p

< 3pu/4, valve V2 is leaking.

> 3pu/4, valve V2 is tight.

FCU 500, FCU 505 · Edition 02.17 47

Page 48

Valve proving system

LZH

7. 2 Test period tP

The test period for the tightness test varies depending

on the selected function (parameter 53).

7.2.1 For one test volume V valves

The test period tP is calculated from:

– Opening times t

– Measurement times t

for V1 and V2,

tP [s] = 2x tL + 2x t

between 2 gas solenoid

V1 V2

450

pu/2

for V1 and V2.

7.2.2 For one test volume Vp1 for system tightness

450

22pu/2

The test period tP is calculated from:

– Opening times t

– Measurement times t

for V1 and V3,

for V1 and V3.

tP [s] = 2x tL + 2x t

FCU 500, FCU 505 · Edition 02.17 48

Page 49

Valve proving system

7.2.3

For two te st volumes for sy stem tightness ( Vp1 + Vp2)

– Measurement time t

to check the test volumes

Vp1 + Vp2 (parameter 57), see page 110 (Measurement time Vp1 and Vp2).

V1 V2

450

pu/2

The test period tP is calculated from:

– Opening time of relief valve V3 to reduce the pressure

of V

, see page 42 (Two test volumes for system

tightness) and page 110 (Opening time relief valve V3),

– Opening times t

for V1 and V2 to check the test vol-

ume Vp1 and test volumes Vp1 + Vp2, see page 42 (Two test volumes for system tightness),

– Measurement times t

for V1 and V2 to check the

test volume Vp1 (parameter 56), see page 110 (Measurement time Vp1),

– Waiting time 1 s,

tP [s] = tL3 + 3x t

L (P59)

+ 2x t

M(P56)

+ t

M(P57)

+ 1

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Valve proving system

VK VK

▼

7.2.4 Extended valve opening time 1 tL1

Standard EN 1643:2000 allows a maximum opening time of 3 s for the tightness test if the main gas valves are actuated directly. If the gas can ﬂow into the combustion chamber when a valve is opened, the gas volume must not exceed 0.05% of the maximum ﬂow rate.

If the pre-set opening time t

= 3 s is inadequate (e.g. if

slow opening motorized valves VK are used) to build up or reduce the test volume pressure, bypass valves with an extended opening time may be used (e.g. VAS 1 or bypass valves with an additional oriﬁce).

1. Tightness test between 2 gas solenoid valves with one test volume (parameter 53 = 1):

141357

VAS 1VAS 1

VK VK

2. System leak tightness check with one test volume and pressure reduction using relief valve (parameter 53 = 2):

VAS 1

3. System leak tightness check with two test volumes and pressure reduction using relief valve (parameter 53 = 3):

14 1513

V1 V2

VAS 1

Current rating of safety interlock output (terminal 57): max. 0.5 A, see also page 127 (Safety interlock output in the case of higher power requirement)

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Valve proving system

▼

Calculation example

Nominal ﬂow rate Q

(N)

P (kW): capacity = 1000 kW H

(kWh/m3):

lower caloriﬁc value of gas type = 10 kW/m

P (kW)

(kWh/m3)

(N)

(m3/h) =

(N)

(m3/h) =

1000 kW

10 kWh/m

= 100 m3/h

Max. gas volume in combustion chamber VO:

VO (l/h) = Q

(m3/h): nominal ﬂow rate = 100 m3/h

(N)

× 0.05%

(N)

(100,000 l/h)

VO (l/h) = 100,000 l/h × 0.05% = 50 l/h

× 0.7

√

2 × p

Required opening time t

400 × V

tL (s) =

π × d

VO (l/h):

max. gas volume in combustion chamber = 50 l/h, d (mm): oriﬁce diameter of bypass valve = 9.45 mm,

ﬂow factor = 0.7,

pu (mbar): inlet pressure = 20 mbar, ρ (kg/m3): density of gas = 0.8 kg/m

400 × 50 l /h

tL (s) =

3.14 × 9.452 × 0.7

√

0.8 kg/m

2 × 20 mbar

= 14.26 s

Enter the next lowest value for parameter 59 (P59 = 14) to set the opening time, see page 112 (Valve opening time 1 t

Calculation module for calculating the opening time t

see page 52 (Calculating the extended valve opening time)

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Valve proving system

Erdgas H

914

BTU/scf

0,049

lb/ft3

3782000

BTU/h

40,0

"WC

3531

SCFH

13,2

Gallon

VAS 6 bis 9

0,70

inch2s

Calculating the extended valve opening time

Metric Imperial

Gas type

Lower caloriﬁc value

Density ρ

Capacity P

Inlet pressure p

Nominal ﬂow rate Q

(N)

Max. gas volume

in combustion chamber VO

VAS 1 on main valve or oriﬁce diameter d

Opening time t

The calculation module can be used to calculate the

opening time tL for the bypass valves (e.g. VAS 1 or bypass valves with additional oriﬁce) by entering the gas type, caloriﬁc value, density, capacity, inlet pressure and oriﬁce diameter.

Set the next lowest value for parameter 59 to set the opening time, see page 112 (Valve opening time 1 t

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Valve proving system

▼

7.2.5 Measurement time tM

The sensitivity of the tightness control in the FCU can

be adjusted for each individual system by adapting the measurement time tM. The longer the measurement time tM, the greater the sensitivity of the tightness control. The measurement time is set using parameters 56 and 57 to a value between 3 and 3600 s – see page 110 (Measurement time Vp1) and page 110 (Measurement time Vp1 and Vp2).

The required measurement time tM is calculated from:

Inlet pressure pu [mbar] Leakage rate QL [l /h]

Test volume Vp1 + Vp2 [l]

Calculation of the test volume – see page 54 (Test volume Vp)

For one test volume V valves or for system tightness)

Adjustable using parameter 56

[s] =

(between 2 gas solenoid

2 × pu x V

(



)

For two test volumes for system tightness (Vp1 + Vp2)

Adjustable using parameter 57

[s] =

For two large test volumes (Vp1 + Vp2) with reduced testing time

Adjustable using parameter 57

[s] =

Conversion into US units – see page 142 (Converting units)

Leakage rate

The FCU tightness control makes it possible to check a

speciﬁc leakage rate Q pean Union, the maximum leakage rate QL is 0.1% of the maximum ﬂow rate Q

Leakage rate QL [l /h] =

2 × pu x (Vp1 + Vp2)

(

0.9 × pu x (Vp1 + Vp2)

(

. Within the scope of the Euro-

[m3/h].

max.

[m3/h] x 1000 [l/h]

max.

1000 x 1 [m



)



)

/h]

For a large test volume Vp1 with reduced testing time

Adjustable using parameter 56

[s] =

FCU 500, FCU 505 · Edition 02.17 53

0.9 × pu x V

(



)

Page 54

Valve proving system

▼

Test volume V

Test volume Vp is calculated from the valve volume VV,

added to the volume of the pipe VR for each additional metre in length L.

Valves Pipework

Type Volume V

VAS 1 0.25 10 0.1 VAS 2 0.82 15 0.2 VAS 3 1.8 20 0.3 VAS 6 1.1 25 0.5 VAS 7 1.4 40 1.3 VAS 8 2.3 50 2 VAS 9 4.3 65 3.3 VG 10 0.01 80 5 VG 15 0.07 100 7.9

VG 20 0.12 125 12.3

VG 25 0.2 150 17.7

VG 40/VK 40 0.7 200 31.4

VG 50/VK 50 1.2 250 49 VG 65/VK 65 2 VG 80/VK 80 4

VK 10 0 8.3 VK 125 13.6 VK 150 20 VK 200 42 VK 250 66

[l] DN

= VV + L x V

Volume per metre

VR [l/m]

The measurement time required for test volumes Vp1

and Vp2 must be set on the basis of the calculation using parameters 56 and 57. For the calculation, see page 55 (Calculation examples).

The measurement time can be set to a value between 3 and 3600 seconds for the test volume V

, and for

Vp1 + Vp2.

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Valve proving system

131415

Calculation examples

2 valves VAS 665,

distance L = 9.5 m, inlet pressure pu = 50 mbar, max. ﬂow rate Q

max.

200 m

= 50 mbar

Leakage rate QL

Test volume V

= 200 m3/h.

max.

VAS 665 VAS 665

9,5 m DN65

200 m

1000 x 1 m

= 1.1 l + 9.5 m x 3.3 l/m = 32.45 l

see page 54 (Test volume Vp)

Test volume V

= 300 l (assumed as an example)

/h x 1000 l/h

(300 l)

= 200 l /h

Measurement time for one test volume V

(between

2 gas solenoid valves or for system tightness)

Parameter 53 = 1 (between 2 gas solenoid valves), parameter 53 = 2 (for system tightness, venting via V3), parameter 70 = 0

2 x 50 mbar x 32.45 l

[s] =

200 l /h

= 16.23 s

Set the next highest value (20 s) using parameter 56, see page 110 (Measurement time V

Measurement time for two test volumes for system tightness (Vp1 + Vp2)

Parameter 53 = 3, parameter 70 = 0

2 x 50 mbar x (32.45 l + 300 l)

[s] =

200 l /h

= 166.23 s

Set the next highest value (170 s) using parameter 57, see page 110 (Measurement time V

and Vp2).

▼

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Valve proving system

Measurement time for a large test volume Vp1 with reduced testing time

Parameter 53 = 1 or 2, parameter 70 = 1

Set the next highest value (10 s) using parameter 56, see page 110 (Measurement time V

Measurement time for two large test volumes (V

+ Vp2) with reduced testing time

Parameter 53 = 3, parameter 70 = 1

0.9 x 50 mbar x (32.45 l + 300 l)

[s] =

Set the next highest value (80 s) using parameter 57, see page 110 (Measurement time V

0.9 x 50 mbar x 32.45 l

[s] =

200 l /h

= 7.3 s

and Vp2).

= 74.8 s

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Valve proving system

7.3 Proof of closure function

The proof of closure function monitors the function of

the gas solenoid valve V1. The proof of closure function can be activated using parameter 51 = 4, see page 108 (Valve proving system).

A limit switch on gas solenoid valve V1 signals the

closed position of the valve to the FCU (terminal 45) for this purpose.

V1 V2

GZL

By checking the closed position using the proof of clo-

sure function, the FCU complies with the requirements of NFPA 85 (Boiler and Combustion Systems Hazards

Code) and NFPA 86 (Standard for Ovens and Furnaces).

Program sequence

Parallel to the fan run-up time (see page 19 (Program sequence)), the FCU checks that valve V1 is in its closed position using the POC switch. If a signal is not received at terminal 45 from the POC switch after a timeout time of 10 s (valve V1 is closed), the FCU performs a fault lock-out with fault message c1.

As soon as the FCU has opened valve V1, it queries the

open position of the valve via the POC switch. If a signal is still received at terminal 45 from the POC switch after a timeout time of 10 s, the FCU performs a fault lockout with fault message c8.

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Page 58

BCSoft

8 BCSoft

The BCSoft engineering tool provides extended access

to the FCU. BCSoft makes it possible to set device parameters on Windows-based PCs in order to adjust the

FCU to the speciﬁc application. In addition, BCSoft pro-

vides extended access to the individual statistics and protocol functions.

In addition to the engineering tool BCSoft, an optoadapter or Bluetooth adapter is required to read the device parameters in and out, see also page 131 (BC Soft).

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Fieldbus communication via Ethernet

9 Fieldbus communication via Ethernet

Proﬁnet and Modbus TCP are manufacturer-independ-

ent, open standards for industrial Ethernet. They cover the requirements for automation technology (manufacturing automation, process automation, drive applications with or without functional safety).

Proﬁnet and Modbus TCP are bus variants for ﬁeldbus

communication, optimized for speed and low connection costs.

FCU

BCM

SPS

BCU 5xx

BCM

BUS

BCM..B2 = PROFINET BCM..B4 = Modbus TCP

BCU 5xx

2 3

BCM

BCU 5xx

The signals from the devices are read into the controller

cyclically. There, they are processed and are then output to the devices again.

The basic function of Proﬁnet and Modbus TCP is the

exchange of process and required data between a controller (e.g. PLC) and several distributed devices (e.g. BCU/FCU).

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Fieldbus communication via Ethernet

9.1 FCU and bus module BCM

The optional bus module BCM 500 is required to inte-

grate the FCU in a ﬁeldbus system (Proﬁnet IO or Modbus TCP).

Control signals (for start, reset and air actuator control),

signal states from the device inputs and outputs and information about the device status (operating states and current program step), warnings and faults can be transferred via the bus module between the FCU and

PLC.

Bus module BCM 500 has two RJ45 connection sock-

ets for connection to the ﬁeldbus on its front. The connection sockets are combined with an internal 2-port switch. This allows the BCM 500 together with the FCU to be integrated in various network topologies (star, tree or line topology). Requirements such as Auto Negotiation and Auto Crossover are satisﬁed.

Safety-related signals and interlocks (e.g. safety interlock) must be routed independently of the ﬁeldbus communication direct from the FCU to the burner control units (e.g. BCU) and vice versa.

L1,

PLC

L1,

BUS

PROFINET/MODBUS TCP

FCUBCM

90° ➔ 0

0 ➔ 90°

5358 55 5254

Temperature controller

3PS

All network components which connect the automation

system and the ﬁeld devices must be certiﬁed for ﬁeldbus use.

For information on planning and the structure of a network and the components to be used (e.g. cables, lines and switches)

for Proﬁnet, see Proﬁnet Installation Guide at ww w.proﬁbus.com, for Modbus TCP, see www.modbus.org.

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Fieldbus communication via Ethernet

9.2 Conﬁguration, planning

Before commissioning, the bus module must be conﬁg-

ured for data exchange with the ﬁeldbus system using an engineering tool or BCSoft.

To do so, ﬁeldbus communication must be activated on

the control unit with connected bus module BCM and the code switches on the BCM set, see also page 118 (Fieldbus communication).

9.2.1 Proﬁnet/Device master data ﬁle (GSD)

In addition to cyclic data exchange, Proﬁnet also provides acyclic data exchange for events which are not constantly repeated such as sending device statistics. In the event that the bus communication is faulty or interrupted and during initialization of the bus communication after switching on, the digital signals are interpreted as “0”.

The technical properties of a device are described by

the manufacturer in a device master data ﬁle (GSD ﬁle).

The GSD ﬁle is required for integration of the device

(BCU/FCU) in the conﬁguration of the PLC. The GSD

ﬁle contains the device image, the communications

properties and all fault messages from the device in text form which are important for the conﬁguration of the Proﬁnet network and the data exchange. Modules deﬁned in the GSD ﬁle may be selected for conﬁguration to integrate the device. The GSD ﬁle for the bus module can be ordered at www.docuthek.com. The steps required to integrate the ﬁle are described in the

instructions for the engineering tool for your automation system.

9.2.2 Modbus TCP

The Modbus protocol is a communications proto-

col based on a Client/Server architecture. Once the

TCP/IP connection between client (PLC) and ser ver

(BCU/FCU) has been established, useful data can be transferred via this connection as often and in as great an amount as required. The PLC and BCU/FCU can establish up to 3 parallel TCP/IP connections at the same time. Using the function codes 3, 6 and 16, data can be transferred to and from the BCU/FCU.

The PLC must send output data to the BCU/FCU at

least ever y 125 ms in order to ensure data transfer and functioning of the BCU/FCU. If the output data is missing or sent too late, the bus module will interpret them as “0”.

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Fieldbus communication via Ethernet

9.2.3 Modules/Registers for process data

All modules (Proﬁnet) and registers (Modbus TCP) re-

quired for data exchange between the PLC and the protective system controls FCU 500/FCU 505 are shown in the following table.

Module (Proﬁnet) Register (Modbus TCP)

Outputs Inputs 6 Status signal 2 9 n r

Fault and warning signals 3 12 n...n+1 r

Remaining times 4 15 n...n+1 r TC remaining times

PLC output information 6 21 n r

FCU input terminal information

FCU output terminal information

STM temperature STL temperature 31 n+2...n+3 r STM/STL status 32 n+4 r

Modbus TCP: see table Modbus TCP – register structure

Only for FCU..C1. Slot 5/address 18 is not transferred with other

device versions.

Proﬁnet

slot

Modbus

address

Address Operation

0 n w

n...n+1 r

5 18 n...n+1 r

24 n...n+1 r 25 n+2 r

8 27 n...n+1 r

30 n...n+1 r

Modbus TCP – register structure

Example of “Inputs” register:

Modbus address 6 Format Word

PLC addres s byte

Byte n

.7 .0

▼

Byte n+1

.7 .0

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Fieldbus communication via Ethernet

Inputs/outputs

The digital input and output signals from the protective

system controls FCU 500 and FCU 505 are included in this module/register.

Input bytes (FCU ➔ PLC)

The input bytes describe the digital signals which are

transferred from the FCU to the digital inputs of the

PLC. The digital signals take up 2 bytes (16 bits).

Bit Byte n B yte n +1 Format

0 Operating signal Max. capacity reached

High temperature

operation

2 FCU system fault Free BOOL 3 Fault lock-out Free BOOL 4 Safety shut-down Free BOOL 5 Warning Free BOOL 6 ON Free BOOL 7 Manual mode Free BOOL

Only with three-point step control via bus.

Min. capacity reached

BOOL

Output byte (PLC ➔ FCU)

The output byte describes the digital signals which

are output by the PLC to the FCU. The digital signals to control the protective system control FCU occupy

1 byte (8 bits).

Parallel to the bus communication, terminals 1 to 4 and 44 of the FCU can be wired. This allows the FCU to be

controlled using the digital signals of the bus communication or the inputs at the terminals.

Bit Byte n Format

0 Reset BOOL 1 Start BOOL 2 Controlled air ﬂow BOOL 3 Burner operation BOOL 4 Free BOOL 5 Free BOOL 6 Open control element, three-point step Open

Close control element , three-point step

Only with three-point step control via bus.

▼

BOOL

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Fieldbus communication via Ethernet

Status signal (FCU ➔ PLC)

This module/register transfers the status signals from

the FCU to the PLC. The status signals occupy one byte (0 to 255). Every status signal is allocated a code.

Bit Byte n

0 1 2 3

Status signals Byte DEC 0 – 255

4 5 6 7

See code table “GSD Codes FCU 500” or

“Modbus Proﬁle FCU 50x” at www.docuthek.com

Data

type

Format Value

Fault and warning signals (FCU ➔ PLC)

The fault and warning signals are transferred from the

FCU to the PLC using this module/register. The fault and warning signals occupy one byte each (0 to 255).

The same allocation table applies to the fault signals

and the warning signals.

Bit Byte n Data t ype Format Value

0 1 2 3

Fault signals Byte DEC 0 – 255

4 5 6 7

Bit Byt e n+1 Data type Format Value

0 1 2 3

Warning signals Byte DEC 0 – 255

4 5 6 7

See code table “GSD Codes FCU 500” or

“Modbus Proﬁle FCU 50x” at www.docuthek.com

▼

FCU 500, FCU 505 · Edition 02.17 64

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Fieldbus communication via Ethernet

Remaining times (FCU ➔ PLC)

This module/register transfers the remaining times of

various processes from the FCU to the PLC. The remaining time occupies 2 bytes.

Bit Byte n B yt e n+1 Data type Format Value

0 1 2 3 4 5 6 7

Remaining times Word DEC

0–6554

(0 to 6554 s)

Remaining times of the valve proving system (FCU ➔ PLC)

Only for FCU..C1.

The module/register in FCU..C0 contains no information.

This module/register transfers the remaining time of

the valve proving system from the FCU..C1 to the PLC.

The remaining time occupies 2 bytes.

The valve check runs parallel to other time-related pro-

cesses, e.g. pre-purge. To display the remaining time of the valve proving system separately, it is transferred separately.

Bit Byte n Byt e n+1 Data type Format Value

0 1 2 3

Remaining time s of the

valve proving system

4 5 6 7

Word DEC

0–6554

(0 to 6554 s)

▼

FCU 500, FCU 505 · Edition 02.17 65

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Fieldbus communication via Ethernet

PLC output information (FCU ➔ PLC)

This module/register transfers information on signals

which the PLC uses to control the FCU back to the PLC.

This allows the signal transfer from the PLC to the FCU

to be checked.

Bit By te n Format

0 Reset BOOL 1 Star t BOOL 2 Controlled air ﬂow BOOL 3 Operating signal BOOL 4 Free BOOL 5 Free BOOL 6 Open control element, three-point step Open 7 Close control element, three -point step Close

Only with three-point step control via bus.

BOOL BOOL

FCU input terminal information (FCU ➔ PLC)

This module/register transfers the signal states of the

digital inputs on the FCU (input terminals) to the PLC.

Bit By te n Byt e n+1 By te n+2 Format

0 Terminal 1 Terminal 48 Terminal 68 BOOL 1 Terminal 2 Terminal 49 Free BOOL 2 Terminal 3 Terminal 50 Free BOOL 3 Terminal 4 Terminal 51 Free BOOL 4 Terminal 44 Terminal 52 Free BOOL 5 Terminal 45 Terminal 65 Free BOOL 6 Terminal 46 Terminal 66 Free BOOL 7 Terminal 47 Terminal 67 Free BOOL

FCU output terminal information (FCU ➔ PLC)

This module/register transfers the signal states of

the digital outputs on the FCU (output terminals) to the PLC.

Bit By te n B yt e n+1 Format

0 Terminal 13 Terminal 53 BOOL 1 Terminal 14 Terminal 54 BOOL 2 Terminal 15 Terminal 55 BOOL 3 Terminal 16 Terminal 56 BOOL 4 Terminal 17 Terminal 57 BOOL 5 Terminal 18 Terminal 58 BOOL 6 Terminal 41 7 Terminal 42 Free BOOL

Only for FCU..F2: terminal 53 is used as an input.

Bit 6 has no function.

Free BOOL

▼

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Fieldbus communication via Ethernet

STM/STL temperature (FCU ➔ PLC)

This module/register transfers the STM temperature

values (for high temperature operation) and STL temperature values (for maximum temperature monitoring)

from the protective system control FCU..H1 to the PLC.

Bytes 1 and 2 are used to transfer the lower of the two

temperature values measured by the double thermocouple to the PLC. The measured temperature must be higher than the set limit value, see page 84 (STM limit value (high temperature operation)).

Bit Byte n B yt e n+1 Data type Format Value

0 1 2 3

STM temperature Word DEC

4 5 6 7

0 – 65535

(0 to 65,535K)

Bytes 3 and 4 are used to transfer the higher of the two temperature values measured by the double thermocouple to the PLC. The measured temperature must be higher than the set limit value, see page 84 (STL/ FSTL limit value (system protection)).

Bit B yte n+2 By te n+3 Data type Format Value

0 1 2 3

STL temperature Word DEC

4 5 6 7

0 – 65535

(0 to 65,535K)

Conversion of temperature values, see www.adlatus.org

Byte 5 is used to send conﬁrmation of whether the values are in the valid range after checking the plausibility of the STL/STM temperature values.

Bit Byte n+4 Format

0 STM, temperature valid BOOL 1 STL , temperature valid BOOL 2 Free BOOL 3 Free BOOL 4 Free BOOL 5 Free BOOL 6 Free BOOL 7 Free BOOL

▼

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Fieldbus communication via Ethernet

9.2.4 Device parameters and statistics

Proﬁnet

With the help of acyclic communication between the

PLC and FCU, it is possible to read information on

parameters, statistics and fault history on an event basis (e.g. using system function block Siemens

FSB 52 RDREC).

Index Description

1001 Parameters 1002 Device statistics, counter 1003 Device statistics, faults/warnings 1004 Operator statistics, counter 1005 Operator statistics, faults/warnings 1006 Fault history 1007 Power module statistics

The available data records differ in terms of their in-

dexes. The contents and description of the indexes are described in the code table “GSD Codes FCU 500” (download from www.docuthek.com).

Modbus TCP

Address Description

256 – 511 Parameter 512 – 767 Device statistics, counter 768 – 1023 Device statistics, faults/warnings 1024 – 1279 Operator statistics, counter 1280 – 1535 Operator statistics, faults/warnings 1536 – 1791 Fault history 1792 – 2047 Power module statistics

The available data records differ in terms of their ad-

dresses. The contents and description of the addresses are described in the code table “Modbus Proﬁle FCU 50x” (download from www.docuthek.com).

FCU 500, FCU 505 · Edition 02.17 68

Page 69

Program step/status

10 Program step/status

DISPLAY

C 1

U I

X. X.

– –

Program step/status

Start-up position/standby

Delay

Approaching minimum capacity

“No ﬂow” state check

Fan run-up time t

Approaching maximum capacity

Low air pressure protection check

Pre-purge

Approaching ignition capacity

Valve check

Delay

Operation/controller enable

Post-purge

Controlled air ﬂow

Remote control (with OCU)

Data transfer (programming mode)

High temperature operation

Device Off

In Manual mode, two dots blink on the display.

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Fault signalling

▼

11 Fault signalling

Fault message (blinking)

Too many remote resets

Controller enable output (trm. 56)

Simultaneous activation (trm. 51, 52)

Actuator wiring (trm. 5255)

Actuator feedback (trm. 52)

Simultaneous Min./Max. bus command

Inconsistent NFS (non-fail-safe) parameters

Inconsistent FS (fail-safe) parameters

Mains voltage

Faulty parameterization

Incompatible bus module

Power module defective

Contactor function check (trm. 68)

Fan not ready for operation

Fuse defective

Inlet valve(s) leaking

Outlet valve(s) leaking

Burner valve(s) leaking

Pressure switch/gas valve wiring

Gas valve wiring

Controller enable/emergency stop

DISPLAY

Description

Remote reset activated > 5 × in 15 min.; faulty input actuation

Controller enable output incorrectly connected/supplied with power from an external source

“Maximum c apacity” and “Ignition capacity” position feedback from butterﬂy valve set simultaneously

Faulty wiring of terminals 52 to 55

Maximum or ignition capacit y is not constantly signalled back to terminal 52

“Open actuator” and “Close actuator” bus signals set simultaneously

Abnormal data change in the parameters set for the FCU

Supply voltage too low or too high

Parameter set contains illegal settings or internal device error

Bus module and control unit are incompatible

Relay contact error

Faulty feedback from contactors

No signal at the “Fan feedback ” input (terminal 44); fan defective

Short-circuit on one of the outputs of the safety circuit

Leak found on inlet valve(s)

Leak found on outlet valve(s)

Leak found on burner valves

Test volume (Vp1 or Vp2) cannot be supplied or vented; faulty pressure switch/gas valve wiring

Reversed valve connection

Interruption of signal at the “Controller enable/Emergency stop” input (terminal 46)

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Fault signalling

▼

Fault message (blinking)

Fuse defective

Permanent remote reset

STL overtemperature

Thermocouple 1 cable discontinuity

Thermocouple 2 cable discontinuity

Thermocouple 1 short-circuit

Thermocouple 2 short-circuit

Temperature difference limit value

Furnace temperature outside range

Burner control unit operating signal

Burner control units not ready

Internal error

Temperature monitoring

Internal error

emBoss

Minimum capacity not reached

Maximum capacity not reached

Ignition capacity not reached

Communication with bus module (display bE)

DISPLAY

Description

Device fuse F1 is defective

Remote reset input activated > 25 s

The safety temperature limiter (STL) has detected an overtemperature condition.

Thermocouple 1 (terminals 5 and 6) defective

Thermocouple 2 (terminals 7 and 8) defective

Sensor short-circuit in thermocouple 1

Sensor short-circuit in thermocouple 2

Set temperature difference between thermocouples exceeded (parameter 23)

Operation outside temperature range

No operating signal within the period deﬁned in parameter 47

Burner control units do not signal Standby mode

Error in processing internal data

Internal fault in module

Error at digital inputs

Error at digital outputs

Error when checking the SFR

Error when reading the EEProm

Error when writing to the EEProm

Shut-down without application error

Closed position not reached after 250 s

Purge position not reached after 250 s

Ignition position not reached after 250 s

Internal communication with bus module has suf fered a fault

FCU 500, FCU 505 · Edition 02.17 71

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Fault signalling

▼

Fault message (blinking)

Parameter chip card (PCC)

(display bc)

POC valve open

(display c1)

POC valve closed

(dis play c8)

Air monitor “no ﬂow” state

(dis play d0)

Low air pressure

(display d1)

Low air pressure

(display d2, d3, d4, d5, d6, d7, d8 or d9)

Air ﬂow during pre-purge

(dis play dP)

High gas pressure

(display o0, o1, o2, o3, o4, o5, o6, o7, o8 or o9)

Bus (display Pb)

DISPLAY

2 3 4 5 6 7 8

0 1 2 3 4 5 6 7 8

Description

Incorrect or defective PCC

No input signal for the valve proof of closure switch (POC) during standby

Input signal for the valve proof of closure switch (POC) does not drop out after burner start-up

Fault Air monitor break contact check; signal from the pressure switches at terminals 47, 48

Fault Air monitor make contact check; no signal from pressure switch at terminal 48

, , ,

No input signal from pressure switch or failure in air supply during program

step 2, 3, 4, 5, 6, 7, 8 or 9

, , ,

No input signal from pressure switch or failure in air supply during prepurge

, , , ,

No input signal from pressure switch at terminal 50 during program step 0,

1, 2, 3, 4, 5, 6, 7, 8 or 9

, , , ,

Bus fault

FCU 500, FCU 505 · Edition 02.17 72

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Fault signalling

Fault message (blinking)

Low gas pre ssure

(display u1, u2, u3, u4, u5, u6, u7, u8 or u9)

DISPLAY

1 2 3 4 5 6 7 8

Description

, , , ,

No input signal from pressure switch at terminal 49 during program step 1,

2, 3, 4, 5, 6, 7, 8 or 9

, , ,

FCU 500, FCU 505 · Edition 02.17 73

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Parameters

▼

12 Parameters

Any changes to parameters will be saved to the parameter chip card.

Name Parameter Value range Description Factory default settings

Emergency stop 10

High gas pressure protection 12

Low gas pre ssure protection 13

Low air pressure protection 15

Safety time during operation tSB 19 0; 1; 2 Time in seconds 1

Temperature monitoring mode 20

Thermocouple 22

Temperature difference limit value 23 10 – 100 Temperature in °C 50

STM limit value (high temperature operation) 24 650 – 1200

STL/FSTL limit value (system protection) 25 200 – 1600 STL/FSTL limit value in °C 350 Temperature hysteresis 26 10 – 100 Temperature in °C 50

Pre-purge during high temperature operation 27

Fan in the event of fault 29

Fan run-up time tGV 30 0 – 6000 Time in seconds 0

Fan ready for operation 31

0 1 2

0 1 2 3

1 2 3

0 1

0 1 2

Off With safety shut-down With fault lock-out

Off STM function STL function STM and STL function

Type K Type N Type S

STM limit value (high temperature operation) in °C

Off On

Off With safety shut-down With fault lock-out

FCU..H0 = 0 FCU..H1 = 2

750

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Parameters

▼

Name Parameter Value range Description Factory default settings

Air monitoring during controlled air ﬂow 32

Pre-purge time tPV 34 0 – 6000 Time in seconds 6000

Air ﬂow monitoring during pre-purge 35

Post-purge time tPN 37 0 – 6000 Time in seconds 6000

Air ﬂow monitoring during post-purge 38

Capacity control 40

Running time selection 41

Running time 42 0 – 250

Controller enable signal delay time tRF 44 0 – 250 Time in seconds 0

Minimum enable time 45 0 – 250

Burner operating signal 46

0 1 2

2 3

0 1 2 3 4

0 1

Off ; maximum capacity On; maximum capacity Off ; controller enable

Off With safety shut-down With fault lock-out

On; control element to maximum capacity Off ; control element to maximum capacity Off ; control element to ignition capacit y Off; control element controller enable

Off With IC 20 With IC 40 With RBW With frequency converter

Off ; checking the positions for minimum/ maximum capacity On; for approaching the positions for minimum/maximum capacity On; for approaching the position for maximum capacity On; for approaching the position for minimum capacit y

Running time in seconds if parameter 41 = 1, 2 or 3

Actuator in ignition position, waiting for enable signal , time in seconds

Off On; controller enable

FCU..F0 = 0

FCU..F1 = 1

FCU..F2 = 3

0 (if P40 = 0) 1 (if P40 ≠ 0)

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Parameters

▼

Name Parameter Value range Description Factory default settings

Controller enable time limit 47 0 – 60

0 1

Valve proving system 51

2 3

4 2

Relief valve (VPS) 52

3 4

Tightness control test volume 53

2 3

Pressure reduction Vp2 54

0 1

Opening time relief valve V3 55 0 – 6000 Time in seconds 0

Measurement time Vp1 56

5–25

30–3600

Measurement time V

and Vp2 57

5–25

30–3600 Valve opening time 1 tL1 59 2 – 25 Time in seconds 2 Valve opening time 2 tL2 60 2 – 25 Time in seconds 2 Minimum pause time tMP 62 0 – 3600 Time in seconds 0 Switch-on delay time tE 63 0 – 250 Time in seconds 0 Filling time before star t-up 65 0 – 25 Time in seconds 0

Operating time in Manual mode 67

0 1

Time in minutes during which the burner must reach its operating position

Off Tightne ss test before start-up Tightne ss test after shut-down Tightne ss test before start-up and af ter shut-down Proof of closure function

V2 V3 V4

Vp1; pressure reduction via V3 Vp1 + Vp2; pressure reduction via V3

In standby Upon star t-up

Time in seconds (in 5 s steps) (in 10 s steps)

Unlimited 5 minutes

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Parameters

▼

Name Parameter Value range Description Factory default settings

Function of terminal 51 69

Function of terminal 65 70

Function of terminal 66 71

Function of terminal 67 72

Function of terminal 68 73

0 1

2 3 4 5 6

0 1 2 3 4 5 6

0 1 2 3 4 5 6 7

0 1 2 3 4 5 6

Off Feedback of position for maximum capacity (IC 40/RBW) AND with emergency stop (trm. 46) AND with air min. (trm. 47) AND with air ﬂow monitoring (trm. 48) AND with gas min. (trm. 49) AND with gas max. (trm. 50)

Off Reduced DG test duration AND with emergency stop (trm. 46) AND with air min. (trm. 47) AND with air ﬂow monitoring (trm. 48) AND with gas min. (trm. 49) AND with gas max. (trm. 50)

Off FCU as zone control unit External HT signal AND with emergency stop (trm. 46) AND with air min. (trm. 47) AND with air ﬂow monitoring (trm. 48) AND with gas min. (trm. 49) AND with gas max. (trm. 50)

Off BCU ready; if not, safety shut-down BCU ready; if not, fault lock-out AND with emergency stop (trm. 46) AND with air min. (trm. 47) AND with air ﬂow monitoring (trm. 48) AND with gas min. (trm. 49) AND with gas max. (trm. 50)

Off Contactor feedback AND with emergency stop (trm. 46) AND with air min. (trm. 47) AND with air ﬂow monitoring (trm. 48) AND with gas min. (trm. 49) AND with gas max. (trm. 50)

FCU 500, FCU 505 · Edition 02.17 77

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Parameters

Name Parameter Value range Description Factory default settings

0 1

Capacity control (bus) 75

Password 77 0000 – 9999 Four-digit number code 1234

Fieldbus communication 80

0 1 2

Off MIN. to MA X. capacit y; standby in position for MIN. capacity MIN. to MA X. capacit y; standby in CLOSED position IGNITION to MAX . capacity; standby in CLOSED position MIN. to MA X. capacit y; standby in position for MIN. capacity; burner quick start IGNITION to MAX . capacity; standby in CLOSED position; burner quick start.

Off With address check No address check

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Parameters

12.1 Scanning the parameters

During operation, the 7-segment display shows the pro-

gram status.

All the parameters of the FCU can be scanned in nu-

merical order by repeatedly pressing the Reset/Information button (for 1 s).

The parameter display is ended 60 seconds after the

last time the button is pressed or by switching off the FCU.

The FCU indicates

switched off. The parameters cannot be scanned when the FCU is switched off or when a fault message is displayed.

when the mains switch has been

12.2 Safety limits

Parameters 10, 12, 13, 15 and 19 can be used to adjust

the safety limits (emergency stop, high gas pressure protection, low gas pressure protection, air monitoring and safety time during operation) to the system requirements.

12.2.1 Emergency stop

Parameter 10

Function of the controller enable/emergency stop input (terminal 46)

This input is the safety interlock input of the FCU. The

properties of this function can be activated/deactivated using parameter 10. If there is no input signal, the FCU will perform a shut-down, depending on the function selected in parameter 10.

On FCU 505 (zone FCU), the function of the controller enable/emergency stop input is different and is not determined by parameter 10.

Parameter 10 = 0: OFF; the function is not required

Parameter 10 = 1: with safety shut-down

A safety shut-down will be performed if there is no sig-

nal at the controller enable/emergency stop input (terminal 46).

Parameter 10 = 2: with fault lock-out

A fault lock-out will be performed if there is no signal

at the controller enable/emergency stop input (terminal 46).

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Parameters

12.2.2 High gas pressure protection

Parameter 12

Function of the gas

input (terminal 50)

max.

If the gas pressure exceeds a speciﬁed value, the high gas pressure protection device will prevent a start-up and trigger a safety shut-down or fault lock-out.

A gas pressure switch DG (high gas pressure protection

device) safeguards the maximum permitted gas pressure. The properties of this function can be activated or deactivated using parameter 12.

Parameter 12 = 0: OFF; the function is not required

Parameter 12 = 1: with safety shut-down

A safety shut-down will be performed if there is no sig-

nal at the gas

input (terminal 50).

max.

Parameter 12 = 2: with fault lock-out

A fault lock-out will be performed if there is no signal at

the gas

input (terminal 50).

max.

12.2.3 Low gas pressure protection

Parameter 13

Function of the gas

input (terminal 49)

min.

The low-pressure cut-off provides veriﬁcation of the gas

pressure when the fan run-up time t

starts to elapse.

If the gas pressure falls below a speciﬁed value, the FCU performs a shut-down, depending on the function selected in parameter 13.

Parameter 13 = 0: OFF; the function is not required

Parameter 13 = 1: with safety shut-down

A safety shut-down will be performed if there is no sig-

nal at the gas

input (terminal 49).

min.

Parameter 13 = 2: with fault lock-out

A fault lock-out will be performed if there is no signal at

the gas

input (terminal 49).

min.

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Parameters

12.2.4 Low air pressure protection

Parameter 15

Equipment ﬁtted with forced or induced draught

burner(s) shall be ﬁtted with devices for proving adequate air ﬂow during pre-purge, ignition and operation of the burner. Any failure of the air ﬂow must trigger a safety shut-down or fault lock-out at any time during pre-purge, ignition or operation of the burners, depending on the requirement of the standard.

The air monitor must be checked when there is no ﬂow

before start-up, for example by stopping the combustion air supply or by interrupting the air signal air

min.

to terminal 47 of the FCU (using a 2/3-way valve). As soon as the combustion air supply is stopped or the signal is interrupted, the fan will start. To start pre-purge, the air monitor must indicate adequate ﬂow for purging. The

ﬂow must be detected within a timeout (250 s). After

the elapse of this timeout, the FCU will perform a shutdown, depending on the function selected in parameter 15.

Parameter 15 = 0: OFF; the function is not required

Parameter 15 = 1: with safety shut-down

A safety shut-down will be performed if there is no input

signal.

Parameter 15 = 2: with fault lock-out

A fault lock-out will be performed if there is no input

signal.

Air ﬂow monitoring during the post-purge time can only

be selected if it has also been activated for pre-purge.

For further information on the function of the signal inputs to monitor the minimum air pressure (air

min.

, terminal 47) and air ﬂow (terminal 48) during pre-purge, see page 89 (Air ﬂow monitoring during pre-purge).

12.2.5 Safety time during operation t

Parameter 19

This parameter can be used to adjust the reaction time

of the FCU to the failure of the ﬂow detectors for air and gas to the requirements of the system.

When selecting the reaction, compliance with the requirements of the relevant system standard must be ensured.

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Parameters

12.3 High temperature operation

The safety temperature limiter (STL) and safety tem-

perature monitor (STM) functions can be adjusted to the requirements of the system using parameters 20,

22, 23, 24, 25 and 27.

These parameters are only available in conjunction with

the STM function (FCU..H1).

12.3.1 Temperature monitoring mode

Parameter 20

Parameter 20 = 0: Off

Temperature monitoring using STL or STM is deacti-

vated.

Parameter 20 = 1: High temperature operation with

STM

Temperature recording to detect high temperature op-

eration (HT operation) of a system without locks, STM

function, automatic reset on return to the permitted

range.

The required double thermocouple must be positioned

at the coldest point in the combustion chamber for this function so that it can reliably detect whether the spontaneous ignition temperature (> 750°C) has been exceeded.

Parameter 20 = 2: Maximum temperature monitoring using STL

Maximum temperature monitoring with fault lock-out, reset after the fault has been eliminated by pressing the button on the front panel or using an externally connected remote reset device.

The required double thermocouple must be positioned

at the warmest point in the combustion chamber for this function so that it can reliably detect whether the maximum permitted temperature has been exceeded.

Parameter 20 = 3: High temperature operation with STM and maximum temperature monitoring with STL

Combination of maximum temperature monitoring with STL function and high temperature operation with STM function. This function may only be used if the position of the double thermocouple is suitable for both functions. The double thermocouple must reliably detect whether the spontaneous ignition temperature (> 750°C) has been exceeded and also whether the maximum permitted furnace temperature has been exceeded.

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Parameters

12.3.2 Thermocouple

Parameter 22

The type of double thermocouple can be selected using

parameter 22.

The following Class 1 double thermocouples may be

used. The thermocouple should be selected on the basis of the switching point for high temperature operation and the maximum furnace temperature that can be reached.

Parameter 22 = 1: Type K double thermocouple NiCrNi

(0 to 1200°C)

Parameter 22 = 2: Type N double thermocouple NiCrSiNiSi

(0 to 1200°C)

Parameter 22 = 3: Type S double thermocouple Pt10RhPt

(0 to 1600°C)

Thermocouples connected to the integrated tempera-

ture module for the safety temperature limiter (STL) and safety temperature monitor (STM) are monitored

for cable discontinuity or short-circuit. This is only pos-

sible with double thermocouples.

It is not permitted to use single thermocouples and connect the inputs in parallel using wire straps. If separate sensor ﬁttings are used, they must be installed next to each other so that they both record the same temperature.

12.3.3 Temperature difference limit value

Parameter 23

The maximum temperature difference (0 to 100K) be-

tween the two double thermocouples is deﬁned using this parameter.

If the temperature difference is exceeded, the FCU will perform a fault lock-out.

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Parameters

12.3.4 STM limit value (high temperature operation)

Parameter 24

This parameter is used to deﬁne the lower limit for high

temperature operation.

The FCU has a fail-safe HT output at terminal 18. This

output is used to signal to the downstream burner control units or automatic burner control units that the system is in High temperature mode (HT).

The FCU does not issue the High temperature mode

enable signal to the burner control units until the lower limit for high temperature operation (parameter 24) plus the set hysteresis (parameter 26) is exceeded. This activates High temperature mode on the burner control units. The burner control units start the burners, without monitoring the presence of the ﬂame.

If the temperature in the furnace chamber falls below the value deﬁned in parameter 24, the FCU disconnects the HT output from the electrical power supply. High temperature mode is deactivated on the burner control units. The furnace is operated with ﬂame control – see also page 123 (High temperature operation).

12.3.5 STL/FSTL limit value (system protection)

Parameter 25

This parameter is used to deﬁne the upper limit of the

furnace or ﬂue gas temperature at which safe operation of the furnace is ensured, depending on the thermocouple used (parameter 22):

Type K, Type N: 200 to 1200°C, Type S: 200 to 1600°C.

If the maximum permitted temperature limit is reached or if an error occurs on the monitoring device within the permitted temperature range (e.g. sensor discontinuity, sensor short-circuit or cable discontinuity), the safety temperature limiter (STL) or ﬂue gas safety temperature limiter (FSTL) will perform a fault lock-out. The safety interlock output will no longer be set.

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Parameters

12.3.6 Temperature hysteresis

Parameter 26

Using the integrated temperature module, the FCU decides either using the safety temperature monitor (STM) whether the conditions for high temperature operation have been met or using the safety temperature limiter (STL) whether the furnace temperature is too high.

To avoid frequent switching in the limit range, a hyster-

esis can be set using parameter 26 for switching the

function selected in parameter 20 (High temperature

operation with STM or Maximum temperature monitoring using STL) on and off.

High temperature operation with STM

FCU 50x..H1

STM

5-8

BCU 4xx..D

µC

BCU 4xx..D

µC

High temperature mode is reactivated as soon as the temperature exceeds the STM limit value and the de-

ﬁned temperature hysteresis.

If the temperature falls below the STM limit value (lower limit for high temperature operation), High temperature mode is ended.

Maximum temperature monitoring with STL

FCU 50x..H1

5-8

STL

BCU 4xx..D

If the limit value of the safety temperature limiter is exceeded (excessive temperature in furnace), the FCU will perform a lock-out. The fault lock-out cannot be reset until the temperature falls below the STL limit value and the deﬁned temperature hysteresis.

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Parameters

12.3.7 Pre-purge during high temperature operation

Parameter 27

Parameter 27 can be used to deﬁne whether the fur-

nace start is performed with or without pre-purge in

High temperature mode. The internal or an external

STM can be used to detect the high temperature.

With the internal STM (FCU..H1), the FCU detects high temperature operation using the limit value deﬁned in parameter 24.

With the external STM, the FCU detects high temperature operation by means of a high signal at terminal 66.

On FCUs with capacity control (FCU..F1, FCU..F2), the

actuator must be moved to ignition position or, if a frequency converter is used, the fan must be accelerated to ignition speed to start the burner. If the FCU..F1 is used in conjunction with actuator IC 20, the ignition position is approached via the purge position.

Parameter 27 = 0: OFF; no pre-purge is performed upon furnace start-up

Parameter 27 = 1: ON; a pre-purge is performed at every

start regardless of the furnace temperature

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Parameters

12.4 Air control

12.4.1 Fan in the event of fault

Parameter 29

This parameter deﬁnes how the fan should act in the

event of a safety shut-down or fault lock-out.

Parameter 29 = 0: OFF; the fan is switched off

Parameter 29 = 1: ON; the fan runs until the start-up

signal is received at terminal 1

12.4.2 Fan run-up time t

Parameter 30

This parameter deﬁnes the time between the activation

of the fan output (terminal 58) and the start of the FCU program sequence (display 01).

The fan run-up time can be parameterized in a range

between 0 and 250 s.

12.4.3 Fan ready for operation

Parameter 31

Using this parameter, it is possible to select whether a feedback from the ready fan is to be taken into consideration by the FCU. The fan sends a binary feedback signal to terminal 44 of the FCU if it is available for operation. If there is no signal, the FCU will perform a shut-down, depending on the function selected in parameter 31.

Parameter 31 = 0: OFF; the function is not required

Parameter 31 = 1: with safety shut-down

A safety shut-down will be performed if there is no input

signal.

Parameter 31 = 2: with fault lock-out

A fault lock-out will be performed if there is no input

signal.

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Parameters

12.4.4 Air monitoring during controlled air ﬂow

Parameter 32

Air control is activated by actuating the controlled air ﬂow input (terminal 2).

After a “no ﬂow” state check of the purge air input (termi-

nal 47, optionally terminal 48), the FCU starts the fan.

Parameter 32 = 0: OFF; maximum capacity.

The actuator is moved to the position for maximum

capacity during controlled air ﬂow. The air ﬂow is not monitored.

Parameter 32 = 1: ON; maximum capacity.

The actuator is moved to the position for maximum

capacity during controlled air ﬂow. The air ﬂow is monitored and taken into account in the subsequent burner start. If the air ﬂow fails, a shut-down will be performed in the same way as during pre-purge.

Flow monitoring only works if air monitoring has

been activated in parameter 15 or parameter 35, see also page 81 (Low air pressure protection) and page 89 (Air ﬂow monitoring during pre-purge).

Parameter 32 = 2: OFF; controller enable.

The controller enable signal (terminal 56) is issued. The

position of the actuator can be changed using an external temperature controller (controlled cooling). The air

ﬂow is not monitored.

Controlled air ﬂow is only possible in standby (with no

start-up signal).

12.4.5 Pre-purge time t

Parameter 34

A burner start may only occur if it has been ensured that

the concentration of inﬂammable components in all sections of the burner tile and the connected areas and the ﬂue gas ducts is less than 25% of the lower ﬂammability limit of the fuel gas. A pre-purge is generally performed to ensure compliance with these requirements.

Parameter 34 is used to parameterize the pre-purge time t

The pre-purge time t

in a range between 0 and 6500 s.

is to be set on the basis of the

relevant application standard (e.g. EN 676, EN 7462, NFPA 85 or NFPA 86).

If air monitoring has been activated in parameter

15 or 35, the pre-purge time t

starts as soon as

the air monitor detects an adequate ﬂow for purging, see page 81 (Low air pressure protection) and page 89 (Air ﬂow monitoring during pre-purge).

FCU 505 (zone FCU)

The duration of the pre-purge started by the FCU 505

is determined by the FCU 500 (furnace FCU). The FCU 505 opens the zone’s butterﬂy valve for purging, depending on the input signals at terminal 46 and terminal 66.

FCU 500, FCU 505 · Edition 02.17 88

Page 89

Parameters

FCU 500

450

LZH

0°

12.4.6 Air ﬂow monitoring during pre-purge

Parameter 35

This parameter can be used to select additional dif-

ferential pressure monitoring of the air ﬂow during pre-

purge. The FCU is informed that there is an adequate air

ﬂow via a signal from the differential pressure switch to

terminal 48 during pre-purge.

PDZ

Parameter 35 = 0: OFF; the function is not required

Parameter 35 = 1: with safety shut-down

A safety shut-down will be performed if there is no input

signal.

Parameter 35 = 2: with fault lock-out

A fault lock-out will be performed if there is no input

signal.

Air ﬂow monitoring is to be set on the basis of the rel-

evant application standard (e.g. EN 676, EN 7462,

NFPA 85 or NFPA 86).

12.4.7 Post-purge time t

Parameter 37

The post-purge time deﬁnes the period during which

air for purging fuel gas residues out of the combustion chamber continues to be supplied to the combustion chamber after furnace operation has been terminated.

Parameter 37 is used to parameterize the post-purge time in a range between 0 and 6500 s (0 to 100 min.).

The conditions set in parameter 38 must be satisﬁed for

the post-purge time to be started.

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Parameters

12.4.8 Air ﬂow monitoring during post-purge

Parameter 38

Parameter 38 deﬁnes whether post-purge takes place

with or without air ﬂow monitoring. Air ﬂow monitoring during the post-purge time can only be selected if it has also been activated for pre-purge (parameter 15 or parameter 35).

Parameter 38 = 0: ON; control element to maximum

capacity.

The actuator is moved to the position for maximum ca-

pacity during the post-purge time. The air ﬂow is monitored.

Parameter 38 = 1: OFF; control element to maximum

capacity.

The actuator is moved to the position for maximum

capacity during the post-purge time. The air ﬂow is not monitored.

Parameter 38 = 2: OFF; control element to ignition ca-

pacity.

The actuator is moved to the position for ignition ca-

pacity during the post-purge time. If the position of the actuator at this time is less than the position for ignition capacity, this position is not changed. The air ﬂow is not monitored.

Parameter 38 = 3: OFF; control element controller en-

able.

The controller enable signal (terminal 56) is issued. The

position of the actuator can be changed using an external temperature controller (controlled cooling). The air

ﬂow is not monitored.

FCU 500, FCU 505 · Edition 02.17 90

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Parameters

1 2 3 46 47 48 49 50

41 4216

17 18 57

62 61 5 6 7 8 11 12

3,15AT

24V

▼

12.4.9 Capacity control

Parameter 40

FCU..F1 and FCU..F2 are ﬁtted with an interface for

connecting air actuators.

They activate a control element or frequency converter

via the outputs for capacity control (terminals 53 to 56)

for purging, cooling or starting the burners. The air ac-

tuator moves to the required position for the relevant operating situation.

Using parameter 40, you can set which actuator is used

for capacity control.

Capacity control via bus, see page 103 (Capacity con-

trol (bus)).

Parameter 40 = 0: OFF; no capacity control (no air ac-

tuator)

Parameter 40 = 1: with IC 20

The interface is conﬁgured to the requirements of ac-

tuators IC 20, IC 20..E, IC 50 or IC 50..E.

Alternatively, comparable three-point step actuators

may be used.

IC 20

4 67 44 52 45 51 65 66 68

13 14 1553

3PS

µC

FCU 500..F1

0°

90°

5AT

The positions for maximum capacity, ignition capacity

and minimum capacity can be set using the actuator. It is checked whether the relevant position has been reached using terminal 52. If the position is not reached within the timeout time of 255 s, the FCU will display fault message A , A or A (minimum, maximum or ignition capacity not reached), see page 70 (Fault signalling).

54 55 56

S11

S1S2

90°➔0°

0°➔90°

3 2 116 67 4812 1115 13

S3 S4

L1 N PE

IC 20

S10

FCU 500, FCU 505 · Edition 02.17 91

Page 92

Parameters

1 2 3 46 47 48 49 50 4 67 44 52

41 4216

17 18 57

13 14 15

62 61 5 6 7 8 11 12

3,15AT

24V

3PS

▼

In the event of a fault, the actuator is moved to the position set via cam S4 for minimum capacity via the output at terminal 54.

Control range between the positions for minimum and maximum capacity

0° 90°

MIN

Burner control range

Butterﬂy valve setting range

Control range

Move to ignition position

MAX

45 51 65 66 68

µC

FCU 500..F1

0°

90°

5AT

54 55 56 53

L1 N PE

90°➔0°

0°➔90°

3 2 116 67 4812 1115 13

S11

IC 20

S10

Min.

Closed

pos.

The control system is enabled for operation via the

controller enable output (terminal 56). During the controller enable procedure, the actuator can be adjusted

S1 S3

Ignition pos.

Max. pos.

inﬁnitely between the positions for maximum and mini-

The minimum position which can be reached is the

closed position.

0° 90°

Burner control range

MIN MAX

CLOSED

Butterﬂy valve setting range

IGNITION

Control range

OPEN

MAX

mum capacity by an external three-point step controller. There is no timeout active in this case.

Control range between the positions for maximum capacity and ignition capacity

The wiring between the FCU and the 3-point step con-

troller can be adjusted so that the control range of the actuator is between the positions for maximum and ignition capacity.

Closed

pos.

Min.

pos.

S1 S3

Ignition pos. Max. pos.

Manual mode

In Manual mode, the actuator can be moved between the positions for maximum and minimum capacity in

3-point step operation. No timeout is active when ap-

Move to ignition position

proaching these positions. The controller enable output (terminal 56) is not active and not checked.

FCU 500, FCU 505 · Edition 02.17 92

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Parameters

1 2 3 46 47 48 49 50

16 17 18 57

62 61 5 6 7 8 11 12

3,15AT

24V

▼

IC 20..E

4 67 44 52 45 51 65 66 68

13 14 1553

µC

5AT

90°

131516

OUT

20 19 18 3 2 167 4812 11

1 2 3 4 5 6

FCU 500..F1

0°

+ +

The positions for minimum capacity, maximum capac-

ity and ignition capacity can be set using the actuator. When the appropriate position has been reached, this information is signalled back via terminal 52.

If no signal is received that the position has been reached within the timeout time of 255 s, a fault lockout of the FCU will be performed and a fault message (A

, A or A) will be displayed, see page 70 (Fault sig-

nalling).

54 55 56

S1 0

IC 20..E

L1 N PE

517

0°

90°

➔

0°

90°

Control range between the positions for minimum and maximum capacity

0° 90°

MIN

Burner control range

Butterﬂy valve setting range

Control range

MAX

Move to ignition position

Closed

pos.

Min.

pos.

S1 S3

Ignition pos.

Max. pos.

The control system is enabled during operation via the

controller enable output (terminal 56). During the controller enable procedure, the actuator can be adjusted inﬁnitely between the positions for maximum and minimum capacity using its analogue input (terminals 17 and 18). There is no timeout active in this case.

Manual mode

In Manual mode, the actuator can be moved between the positions for maximum and minimum capacity in

3-point step operation. No timeout is active when ap-

proaching these positions. The controller enable output (terminal 56) is not active and not checked.

FCU 500, FCU 505 · Edition 02.17 93

Page 94

Parameters

0 V

1 2 3 46 47 48 49 50 4 67 44 52

41 4216

17 18 57

13 14 15

62 61 5 6 7 8 11 12

STW/

STB

LDS

+ - + -

3,15AT

24V DC

k11 k21

IN × 0,6

IC 40

Parameter 40 = 2: with IC 40

The interface is conﬁgured according to the require-

ments of actuator IC 40 with an optional analogue input. Operating mode 27 must be parameterized on the

IC 40 to ensure communication with the FCU.

45 51 65 66 68

22 21 20

µC

FCU 500..F1

5AT

19 18 16 15 14 12 11 10 8 7 5 4 2 1

54 55 56 53

DI 2

IC 40

DI 1

L N

tion capacity. If the position is not reached within the timeout time of 255 s, a fault lock-out of the FCU will be performed. A fault message (A

, A or A) will be dis-

played, see page 70 (Fault signalling).

If a controller enable is active, the control system is enabled for operation via the outputs at terminals 53 and 55.

During the controller enable procedure, the actuator IC 40 can be adjusted inﬁnitely between the positions for maximum and minimum capacity using its analogue input (terminals 18 and 19). There is no timeout active in this case.

R..

The positions for maximum capacity and ignition

capacity can be set using the actuator. Terminal 51 checks whether the position for maximum capacity has been reached. Terminal 52 checks the position for igni-

FCU 500, FCU 505 · Edition 02.17 94

Page 95

Parameters

▼

Purge

0–20

Ignition

Closed

DI 1

DI 2

FCU IC 40

Signal at terminal

Position Butterﬂy valve position

55 53

Off Off Closed Closed On Off Ignition Minimum/Ignition capacity

On On 0–20 mA

Any position between minimum and

maximum capacity

Off On Open Maximum capacit y

In the event of a fault, there will be no signal at terminals 53 and 55 so that the actuator moves to the closed position. When approaching the closed position, no timeout of 255 s is active since no feedback input is checked. This may result in a situation where the program is continued in the case of a request for the closed position, without the butterﬂy valve being

t [s]

closed. The outputs at terminals 56 (controller enable) and 54 (closed position) on the FCU are non-functional and are not activated.

Manual mode

In Manual mode, no external controller is enabled. The actuator can be moved to the positions for maximum capacity or ignition capacity by the user. 3-point step operation is not possible. No timeout is active when approaching these positions.

FCU 500, FCU 505 · Edition 02.17 95

Page 96

Parameters

1 2 3 46 47 48 49 50 4 67 44

41 4216

17 18 57

13 14 15

62 61 5 6 7 8 11 12

STW/

STB

0 V

LDS

+ - + -

3,15AT

24V

k11 k21

IN × 0,6

1 2 3 46 47 48 49 50 4 67 44

41 4216

17 18 57

13 14 15

62 61 5 6 7 8 11 12

STW/

STB

0 V

LDS

+ - + -

3,15AT

24V

k11 k21

IN × 0,6

▼

RBW

Parameter 40 = 3: with RBW

The actuator can be moved to the positions for maxi-

mum capacity (contact COM to HI) and minimum capacity (contact COM to LO) using the interface and by closing the various contacts.

52 45 51 65 66 68

AUTO

90°➔0°

5AT

AUTO

COM

54 55 56 53

R B W

54 55 56 53

+ F -

µC

FCU 500..F2

52 45 51 65 66 68

0°➔90°

RBW

µC

FCU 500..F2

OUT

PLC

The RBW actuator reports that it has reached the posi-

tion for maximum capacity via a signal to terminal 51.

The actuator reports that it has reached the position

for minimum capacity via a signal to terminal 52. The simultaneous activation of terminals 51 and 52 results in a fault lock-out of the FCU.

If parameter 41 = 0, the system monitors the movement to the positions for maximum and minimum capacity with a timeout time of 255 s. Reaching the relevant position immediately triggers the program continue switch conditions. If reaching the position is not signalled within the timeout time of 255 s, a safety shutdown of the FCU will be performed. A fault message (A

or A ) will be displayed, see page 70 (Fault signal-

ling).

L1 N

If parameter 41 = 1, the system does not monitor whether the positions for minimum and maximum capacity are reached. In this case, a running time of up to 250 s must be deﬁned using parameter 42, see page 100 (Running time). The program continue switch conditions are then controlled dependent on this time.

If a fault occurs, the actuator is moved to the position for minimum capacity.

0°➔90°

RBW

FCU 500, FCU 505 · Edition 02.17 96

L1 N

Page 97

Parameters

▼

FCU RBW (three-point step control)

Contact between terminals Position Butterﬂy valve position

53 55 Ignition Minimum/Ignition capacity

53 56 0–20 mA

53 54 Purge Maximum capacity

Manual mode

In Manual mode, no external controller is enabled during the controller enable procedure. The actuator can be moved to the positions for maximum capacity or ignition capacity by the user. 3-point step operation is not possible. No timeout is active when approaching these positions.

Any position between minimum

and maximum capacity

FCU 500, FCU 505 · Edition 02.17 97

Page 98

Parameters

1 2 3

41 42

17 18 57

62 61 5 6 7 8 11 12

STW/

STB

0 V

+ - + -

k11 k21

IN × 0,6

3,15AT

24V

▼

Frequency converter

Parameter 40 = 4: with frequency converter

The interface is conﬁgured according to the require-

ments of a frequency converter for fans.

47 48 4 67 44 52 45 51 65 66 68

PLC

0–100%

µC

FCU 500..F2

Target = actual

5AT

13 14 1553

AUTO

54 55 56

COM

DI 3DI 2DI 1

The FCU bridges the connections at terminals 53

and 54 (COM – HI bridge) for pre-purge. The frequency converter accelerates the fan to the speed for maximum capacity with a timeout of 255 s.

The frequency converter reports that the speed for

maximum capacity has been reached by a signal (target = actual) to the FCU via terminal 52.

After the elapse of the pre-purge time, the FCU bridges

the connections at terminals 53 and 55 (COM – LO bridge). The frequency converter accelerates the fan to the speed for minimum capacity (ignition capacity) with a timeout of 255 s. The frequency converter reports that the speed for minimum capacity (ignition capacity) has been reached by a signal (target = actual) via terminal 52. As soon as the burner operating signal has been received, the FCU bridges the connections at terminals

53 and 56 (COM – AUTO bridge). This disconnects the outputs at terminals 54 and 55 from the voltage supply to issue the controller enable signal to the frequency converter. During the controller enable procedure, the speed of the fan can be adjusted inﬁnitely between minimum and maximum capacity using the analogue input of the frequency converter. There is no timeout active in this case.

P100 08

PZPDZ

54 55

Target = actual

Controller enable

FCU 500, FCU 505 · Edition 02.17 98

Page 99

Parameters

FCU Frequency converter

Contact between terminals Signal to Position Fan speed

53 55 DI 2 /DI 3 Ignition Minimum/Ignition capacity 53 56 DI 3 0–20 mA Any speed between minimum and maximum capacity 53 54 DI 1/DI 3 Purge Maximum capacity

Manual mode

In Manual mode, the frequency converter can be set to the speed for maximum air volume or minimum air volume (pilot air volume). Adjustment by the control system is not possible. No timeout is active when accelerating to these speeds.

FCU 500, FCU 505 · Edition 02.17 99

Page 100

Parameters

12.4.10 Running time selection

Parameter 41

Parameter 41 is only active if parameter 40 = 3 (actua-

tor with RBW function).

Parameter 41 = 0: Off; checking the positions for mini-

mum/maximum capacity. A signal that the positions for minimum and maximum capacity have been reached is returned and monitored with a timeout time of max.

255 s. When the position has been reached, the FCU

will initiate the next program step.

Parameter 41 = 1: On; for approaching the positions for

minimum/maximum capacity. The Running time set using parameter 42 is activated for approaching these positions. After this time has elapsed, the FCU will initiate the next program step.

Parameter 41 = 2: On; for approaching the position for

maximum capacity. The Running time set using pa-

rameter 42 is activated for approaching the position for maximum capacity. After this time has elapsed, the FCU will initiate the next program step. Approaching

the position for minimum capacity is signalled and

monitored.

Parameter 41 = 3: On; for approaching the position for minimum capacity. No signal is returned that the position for minimum capacity has been reached. The Running time set using parameter 42 is activated for approaching the position for minimum capacity. After this time has elapsed, the FCU will initiate the next program step. Approaching the position for maximum capacity is signalled and monitored.

12.4.11 Running time

Parameter 42

Parameter 42 is only active if parameter 40 = 3 and parameter 41 = 1, 2 or 3.

This parameter sets the running time of the RBW actua-

tor (0 to 250 s). Feedback for maximum or minimum capacity position (HI or LO) is not queried.

The actuator can be moved by bus signals or an exter-

nal controller during the controller enable procedure.

There is no timeout active in this case.

In Manual mode, no external controller is enabled during the controller enable procedure. The actuator can be moved to the positions for maximum or minimum capacity by the user. 3-point step operation is not possible. No timeout is active when approaching these positions.

FCU 500, FCU 505 · Edition 02.17 100

Kromschroder FCU 500, FCU 505 Technical Information

Specifications and Main Features

Frequently Asked Questions

User Manual

Protective system controls FCU 500, FCU 505

Contents

1 Application

1.1 Application examples

ON/OFF ro tar y impul se contr ol

1.1.2 Modulating burner control

1.1.3 Safety limits (LDS) for modulating burner control

1.1.4 Flame control using the temperature

1.1.5 Furnace and zone control

3 Function

3.1 Connection diagram

3.1.1 FCU 500

3.1.2 FCU 505

3.1.3 Assignment of connection terminals

3.2 Program sequence

3.2.1 FCU 500..F0

3.2.2 FCU 500..F1, FCU 500..F2

3.2.3 FCU 505..F1, FCU 505..F2

3.3 Animation

4 Temperature monitoring

4.1.1 With integrated STM

4.1.2 With external STM

4.1.3 With integrated and external STM

4.2.1 With integrated STL/FSTL

4.2.2 With external STL/FSTL

5 Air control

5.2 Capacity control

6 Furnace zone control

7 Valve proving system

7.1 Tightness control

7.1.1 Test instant

7.1.2 One test volume between 2 gas solenoid valves

7.1.3 One test volume for system tightness

7.1.4 Two test volumes for system tightness

7.1.5 Large test volumes with reduced testing time

7. 2 Test period tP

7.2.2 For one test volume Vp1 for system tightness

For two te st volumes for sy stem tightness ( Vp1 + Vp2)

7.2.4 Extended valve opening time 1 tL1

7.2.5 Measurement time tM

7.3 Proof of closure function

8 BCSoft

9 Fieldbus communication via Ethernet

9.1 FCU and bus module BCM

9.2.2 Modbus TCP

9.2.3 Modules/Registers for process data

9.2.4 Device parameters and statistics

10 Program step/status

11 Fault signalling

12 Parameters

12.1 Scanning the parameters

12.2 Safety limits

12.2.1 Emergency stop

12.2.2 High gas pressure protection

12.2.3 Low gas pressure protection

12.2.4 Low air pressure protection

12.3 High temperature operation

12.3.1 Temperature monitoring mode

12.3.2 Thermocouple

12.3.3 Temperature difference limit value

12.3.4 STM limit value (high temperature operation)

12.3.5 STL/FSTL limit value (system protection)

12.3.6 Temperature hysteresis

12.3.7 Pre-purge during high temperature operation

12.4 Air control

12.4.1 Fan in the event of fault

12.4.3 Fan ready for operation

12.4.9 Capacity control

12.4.10 Running time selection

12.4.11 Running time