7 495 Boiler Management Unit (BMU) LMU74... LMU75... LMU7 are digital Boiler Management Units (BMUs) for use in gas-fired appliances equipped with premixing burners. LMU74 without combustion optimization LMU75 with combustion optimization The LMU7 and this Data Sheet are intended for use by OEMs which integrate the BMUs in their products. Use The LMU7... provide all supervisory and control functions required for burner, space heating and DHW operation and using integrated communication interfaces facilitate modular system extensions. They are especially suited for: Premixing or condensing gas-fired appliances with burners modulating via PWM fan and pneumatic gas / air ratio control in intermittent operation, with direct ignition of the main flame Capacity ranges < 70 kw, 70...120 kw and > 120 kw Heating boilers or combi boilers with DHW storage tanks or instantaneous DHW heaters Attention! All safety, warning and technical notes given in the Basic Documentation of the LMU7 (P7495) and in the User Manual (U7495) also apply to this document!
Supplementary documentation Environmental Product Declaration LMU74... / LMU75...... E7495 Extended OEM User Manual (setting lists)... I7495 Extended OEM User Manual (setting lists) Sitherm Pro... I7495.1 Basic Documentation LMU7...... P7495 Basic Documentation Sitherm Pro... P7495.1 Product Range Overview LMU7... Q7495 User Manual LMU7... U7495 Presentation of product The basic unit of the LMU7 is a combination of burner control and heating controller. It has no operating elements. Operation is effected via detached operator units and room units. The scope of functions includes: Safety and supervisory functions / protective functions for the plant DHW and heating circuit control Integration in system applications (cascades, zones, etc.) Operation / service / maintenance Parameter settings Integrated mains transformer Optional system extensions (using ClipIns) Programmable relay output / programmable digital input 2/18
Standards and certificates Applied directives: Low-voltage directive 2006/95/EC and 2014/35/EC Directive for gas-fired appliances 2009/142/EC Electromagnetic compatibility EMC (immunity) *) 2004/108/EC *) The compliance with EMC emission requirements must be checked after the Boiler Management Unit is installed in equipment Compliance with the regulations of the applied directives is verified by the adherence to the following standards / regulations: Automatic burner control systems for burners and appliances DIN EN 298 burning gaseous or liquid fuels Automatic electrical controls for household and similar use DIN EN 60730-2-5 Part 2-5: Particular requirements for automatic electrical burner control systems Safety and control devices for gas burners and gas burning DIN EN 13611 appliances Gas/air ratio controls for gas burners and gas burning appliances Part 2: Electronic types DIN EN 12067-2 The relevant valid edition of the standards can be found in the declaration of conformity! EAC Conformity mark (Eurasian Conformity mark) ISO 9001:2008 ISO 14001:2004 OHSAS 18001:2007 Life cycle Boiler Management Units LMU7... has a designed lifetime* of 250,000 burner startup cycles which, under normal operating conditions in heating mode, correspond to approx. 10 years of usage (starting from the production date given on the type field). This lifetime is based on the endurance tests specified in standard EN 298 and the table containing the relevant test documentation as published by the European Association of Component Manufacturers (Afecor) (www.afecor.org). The designed lifetime is based on use of the BMUs according to the manufacturer s Data Sheet and Basic Documentation. After reaching the designed lifetime in terms of the number of burner startup cycles, or the respective time of usage, the BMU is to be replaced by authorized personnel. * The designed lifetime is not the warranty time specified in the Terms of Delivery 3/18
Mechanical design QAA75... QAA55... REA02... REA11... RVS... ACS... / OCI... OCI420... AGU2.5... LMU7... VGU... AGU3... AVS37.294 AVS37.390 Basic operator unit (PCB version) 7475b02e/0513 4/18
Technical data LMU7... General Operating voltage +10 % / -15 % Note! Ensure that conductors L and N are correctly connected! Mains frequency 50 Hz ±5 % Power consumption Max. 17 VA (without any loads) Rated surge voltage category III ( to DIN EN 60 664) Degree of protection IP00 IP40 (must be ensured after integration into the boiler) Safety class sections of safety class 0 and sections of SELV Degree of contamination 2 Software classes - Controller section - Burner control to DIN EN 60 730-2-5 class A class C Dimensions (L x H x D) 180 x 180 x 45 mm Weight approx. 0.8 kg Unit fuse T6.3H250 Mounting position optional Environmental conditions Storage DIN EN 60 721-3-1 class 1K3 class 1M2 Temperature range -20...+60 C < 95 % r.h. (non-condensing) Transport DIN EN 60 068-2-30 and DIN EN 60 730-2-5, chapter 12 class 2K2 class 2M2 Temperature range -20...+60 C < 95 % r.h. (non-condensing) Vibration DIN EN 60 721-3-2 Operation DIN EN 60 721-3-3 class 3K3 class 3M2 Temperature range 0...+60 C < 95 % r.h. (non-condensing) Attention! Condensation, formation of ice and ingress of water are not permitted! 5/18
Technical data (cont d) Electrical connections Total current of all mains components connected to the LMU7... and the ClipIns Mains extension (X1-02) fan (X2-01) K1 (X2-02) K2 (X2-03) K3 (X2-04) Flame supervision / ionization probe (X2-05) - Switching thresholds - Response time in the event of loss of flame - Touching of flame detector Safety limiter (X3-01) Fuel valve (X3-02) - AC output 5 A (at UN = ; Tu = 60 C) +10 % / -15 % Depending on power consumption heating circuit pump, programmable output, fuel valve, DHW charging pump, external ignition transformer and used ClipIn +10 % / -15 % Depending on used fan +10 % / -15 % 5 ma 1 A, cos >0.8 +10 % / -15 % 5 ma 1 A, cos >0.8 +10 % / -15 % 5 ma 1 A, cos >0.8 Min. 0.8 µa (required DC) Typical 1.6 µa Max. 2.4 µa <1 s Not permitted 1 m +10 % / -24 % 5 ma 1 A, cos > 0.6 carrying power supply for fuel valve and ignition +10 % / -24 % valve must still open at AC 175 V 5 ma 0.5 A, cos > 0.8 Note: Fuel valves with rectifier may be connected to the fuel valve output only after consultation with Siemens! In that case, additional protective measures inside the LMU7 are required (optional PCB). RAC output - Pmax General data for fuel valve connection - Leak current at 1.06 x rated voltage - Capacitive extra circuitry or surge voltage limiting protective elements R +10 % / -15 %, 100 Hz valve must still open at AC 175 V 20 W, cos > 0.9 Max. 3 m Max. 0.5 ma Not permitted 6/18
Technical data (cont d) External ignition module (X3-03) +10 % / -15 % 5 ma 0.5 A, cos > 0.8 must still ignite at AC 175 V Max. 3 m Any external ignition modules used must be approved by Siemens to ensure their switching performance meets the requirements! Fan speed (X14) Refer to separate Siemens specification: Spezifikation_LMU5x_TrafoGebläse_de_VX.Y.doc (mandatory) Boiler temperature sensor (X11) - Continuously temperature - Short-time temperature - Sensor tolerance - Aging - - Other requirements - Temperature resistance characteristic NTC 10 k Max. 100 C Max. 125 C ±2 K 3 m ±3 % 20 s To DIN EN 60 730-2-9 Temperature [ C] RNTC [k] Temperature [ C] RNTC [k] -20.00 96.360 50.00 3.605-10.00 55.047 60.00 2.490 0.00 32.555 70.00 1.753 10.00 19.873 80.00 1.256 20.00 12.488 90.00 0.915 25.00 10.000 100.00 0.677 30.00 8.059 110.00 0.508 40.00 5.330 120.00 0.387 Remarks: QAx36... must be used depending on relevant specification. Return temperature sensor (X11) DHW temperature sensor (X11) Flue gas sensor (X11) Outside sensor (X10-06) NTC 10 k Described above under boiler temperature sensor NTC 10 k Refer to specification QALx6 10 m (When connecting a thermostat to the DHW sensor input, high-quality contact material (e.g. gold-plated contacts) must be used since the signal voltage at this input is DC 5 V NTC 10 k Refer to specification QAx3 3 m NTC 1 k Refer to specification QAC34 40 m 7/18
Technical data (cont d) Pressure sensor (X11) - Output voltage LMU7... - Input voltage LMU7... - Huba Control - Huba Control - Imit Heating circuit Flow Switch (X11) - Output voltage LMU7... - Contact resistance DHW Flow Switch (X11) - Output voltage LMU7... - Contact resistance Safety shutdown / gas pressure switch (X10-03) - Output voltage LMU7... - Contact resistance Programmable digital input / air pressure switch (X10-04) - Output voltage LMU7... - Contact resistance Room thermostat / time switch 2 (X10-01) Room thermostat 1, time switch 1 (X10-02) - Output voltage LMU7... - Contact resistance Stepper motor control for combustion optimization (X12) Min. DC 9 V at 5 ma Typical DC 14 V at 5 ma Max. DC 19 V at 5 ma Max. DC 20 V at 0 ma Max. 10 ma DC 5 V (measuring range 0.5 3.5 V) with a load of 12 k 3 m 0 4 bar (type 502) 0 10 bar (type 503) On request Min. RAC 19 V at 7 ma Typical at 10 ma Max. RAC 31.5 V at 12 ma (50 Hz half-wave rectified) Max. 300 3 m Min. RAC 19 V at 7 ma Typical at 10 ma Max. RAC 31.5 V at 12 ma (50 Hz half-wave rectified) Max. 300 3 m Min. RAC 19 V at 7 ma Typical at 10 ma Max. RAC 31.5 V at 12 ma (50 Hz half-wave rectified) Max. 300 5 m Min. RAC 19 V at 7 ma Typical at 10 ma Max. RAC 31.5 V at 12 ma (50 Hz half-wave rectified) Max. 300 5 m Min. RAC 19 V at 7 ma Typical at 10 ma Max. RAC 31.5 V at 12 ma (50 Hz half-wave rectified) Max. 300 40 m Refer to VGU specification 1 m 8/18
Technical data (cont d) Electrical connections BSB users Operator unit (X30) Room unit (X16) - Connection - Cable resistance - Cross-sectional area Users PWM control for heating circuit pump (X11) - PWM frequency - Output voltage LMU7... DHW thermostat of the DHW sensor input AVS37... QAA55... / QAA75... 2- or 3-wire Max. 200 m Max. 3 x 14 Min. 0.5 mm² Max. 4 (1 operator unit, 2 room units, 1 service unit) Preconditions: 1. Only one QAA75... or two QAA55... may be connected via 2-wire! 2. Max. 3 units may be connected via 3-wire! 1.536 khz ±2 % Min. DC 5 V at 5 ma Typical DC 10 V at 7 ma Max. DC 15 V at 10 ma Max. DC 20 V at 0 ma 3 m DC 5 V 1.5 ma Cable length LMU7... ClipIn) - Connection LMU7... ClipIn (OCI420... / AGU2.500...) Max. 1 m Connectors Connection Component Connector type * X11 LMU7... external sensor Connector (RAST2.5) 13-pole Suppliers e.g. Lumberg Duomodul 3521 13 K00 X12 LMU7... VO stepper motor Connector (RAST2.5) 6-pole Suppliers e.g. Lumberg Duomodul 3521 06 K00 X14 LMU7... Connector (RAST2.5) 4-pole Suppliers e.g. Lumberg Duomodul 3521 04 K00 X30 LMU7... to AVS37 Connector (RAST2.5) 5-pole Suppliers e.g. Lumberg Duomodul 3515 06 K23 X40 LMU7... to OCI Connector (RAST2.5) 5-pole Suppliers e.g. Lumberg Duomodul 3515 05 K04 X50 LMU7... to AGU2.500 Connector (RAST2.5) 5-pole Suppliers e.g. Lumberg Duomodul 3515 05 K04 * Connector required for the component (to be provided by OEM). Recommended cross-section area of cable for X11...X15: 0.38 mm² 9/18
Technical data (cont d) ClipIn AGU2.500... Outputs Electrical connection Mechanical design - AGU2.500x109 - AGU2.500x209 Mixing circuit pump and mixer - Mains frequency Housing version PCB version +10 % / -15 % 5 ma 1 A, cos >0.8 50 Hz ±5 % Note: With regards to the outputs, the total current draw of the LMU7... system must be taken into consideration! Degree of protection IP00 Min. IP40 (must be ensured when fitted inside the boiler) Safety class Parts of safety class 0 and of SELV Degree of pollution 2 Software classes To DIN EN 60 730-2-5 - Controller part Class A Housing - Material - Color - Flame protection class Polycarbonate RAL 7035 (light-grey) To UL 94: V-2 Environmental conditions Storage DIN EN 60 721-3-1 Class 1K3 Class 1M2 Temperature range -20...+60 C Transport DIN EN 60 068-2-30 and DIN EN 60 730-2- 5 chapter 12 Class 2K3 Class 2M2 Temperature range -20...+70 C Vibration DIN EN 60 721-3-2 Operation DIN EN 60 721-3-3 Class 3K3 Class 3M2 Temperature range 0...+60 C Warning! Condensation, formation of ice and ingress of water are not permitted! Conformity with EEC directives - Electromagnetic compatibility EMC (immunity) 2004/108/EC Input Flow sensor NTC 10 k Same as boiler sensor 10/18
Technical data (cont d) ClipIn AGU2.51... Outputs Maximum 3 outputs (K1...K3) When using 2 ClipIns with the LMU7..., only 2 outputs possible Electrical connection - Mains frequency +10 % / -15 % 5 ma 1 A, cos >0.8 50 Hz ±5 % Note: With regard to the outputs K1...K, the total current draw of the LMU7... system must be taken into consideration! Degree of protection Safety class Degree of pollution 2 Software classes - Controller part Housing - Material - Color - Flame protection class IP00 Min. IP40 (must be ensured when fitted inside the boiler) Parts of safety class 0 and of SELV To DIN EN 730-2-5 Class A Polycarbonate RAL 7035 (light-grey) To UL 94: V-2 Environmental conditions Storage DIN EN 60 721-3-1 Class 1K3 Class 1M2 Temperature range -20...+60 C Transport DIN EN 60 068-2-30 and DIN EN 60 730-2- 5 chapter 12 Class 2K3 Class 2M2 Temperature range -20...+70 C Vibration DIN EN 60 721-3-2 Operation DIN EN 60 721-3-3 Class 3K3 Class 3M2 Temperature range 0...+60 C Warning! Condensation, formation of ice and ingress of water are not permitted! Conformity with EEC directives - Electromagnetic compatibility EMC (immunity) 2004/108/EC Input Type reference Input Note AGU2.511A109 0...10 V Observe polarity AGU2.513A109 (0)4...20 ma Observe polarity AGU2.514A109 NTC 10 k Same as boiler sensor AGU2.515A109 1) 1) Contact rating: Nom. DC 34 V / 5 ma Note: Only safety extra low-voltage (SELV) may be applied to the inputs. Also, the inputs must not be connected to PE! 11/18
Technical data (cont d) Solar ClipIn AGU2.530A109 Outputs Electrical connection Free programmable - Mains frequency +10 % / -15 % 5 ma 1 A, cos >0.8 50 Hz ±5 % Note With regard to the outputs, the total current draw of the LMU7... system must be taken into consideration! Degree of protection IP00 Min. IP40 (to be ensured when fitted inside the boiler) Safety class Parts of safety class 0 and of SELV Degree of pollution 2 Software classes To DIN EN 730-2-5 - Controller part Class A Housing - Material - Color - Flame protection class Polycarbonate RAL 7035 (light-grey) To UL 94: V-2 Environmental conditions Storage DIN EN 60 721-3-1 Class 1K3 Class 1M2 Temperature range -20...+60 C Transport DIN EN 60 068-2-30 and DIN EN 60 730-2- 5 chapter 12 Class 2K3 Class 2M2 Temperature range -20...+70 C Vibration DIN EN 60 721-3-2 Operation DIN EN 60 721-3-3 Class 3K3 Class 3M2 Temperature range 0...+60 C Warning! Condensation, formation of ice and ingress of water are not permitted! Condensation, formation of ice and ingress of water are not permitted! Conformity with EEC directives - Electromagnetic compatibility EMC (immunity) 2004/108/EC Input Collector sensor NTC 10 k 12/18
Technical data (cont d) LPB ClipIn OCI420 Environmental conditions Degree of protection IP00 Min. IP40 (must be ensured when fitted inside the boiler) Safety class III (SELV) Degree of pollution 2 Software classes To DIN EN 730-2-5 - Controller part Class A Housing - Material - Color - Flame protection class Polycarbonate RAL 7035 (light-grey) To UL 94: V-2 Storage DIN EN 60 721-3-1 Class 1K3 Class 1M2 Temperature range -20...+60 C Transport DIN EN 60 068-2-30 and DIN EN 60 730-2- 5 chapter 12 Class 2K3 Class 2M2 Temperature range -20...+70 C Vibration DIN EN 60 721-3-2 Operation DIN EN 60 721-3-3 Class 3K3 Class 3M2 Temperature range 0...+60 C Warning! Condensation, formation of ice and ingress of water are not permitted! Conformity with EEC directives - Electromagnetic compatibility EMC (immunity) 2004/108/EC External components RAST5 connector Insulation displacement connector E.g. Lumberg type 3625 (stranded wire 1 1.5 mm²) or Connector with screwed terminals E.g. Lumberg type 3611 (stranded wire up to 2.5 mm²) Fan with DC 24 V motor Nominal data Refer to separate Siemens specification Spezifikation_LMU5x_TrafoGebläse_de_VX.Y.doc (mandatory) 13/18
Functions Heat source boiler Heat source solar Heating circuit control DHW temperature control Electronic temperature controller Minimum and maximum limitation of the boiler temperature Optimum start control with minimum limitation of the boiler temperature Boiler overtemperature protection (pump overrun) Burner cycling protection via minimum burner running time Frost protection boiler Forced intermittent operation Burner control programs for 3 capacity ranges Acquisition of actual values Flue gas temperature supervision Electronic (safety) limit thermostat Temperature limiter function Proof of flow / water pressure supervision Pressure sensor Output / speed limitation Ionization current limitation / ionization current supervision Burner lock Continuous pump run Boiler control Determination of compensation variants Consumer management (CM) Modulating pump with delta-t supervision DHW storage tank charging solar Overtemperature protection collector and storage tank Frost protection solar Pure weather compensation Weather compensation with room temperature influence Pure room temperature compensation 1st pump circuit with 7-day program 2nd mixing / pump circuit with 7-day program Virtual room model Automatic adaptation of heating curve Automatic summer / winter changeover Automatic 24-hour heating limit Holiday program Quick setback and boost heating Optimum start / stop control Increase of reduced temperature level as a function of the outside temperature Floor curing function Frost protection for flow and plant DHW storage tank charging with 7-day program DHW charging with charging pump or diverting valve DHW charging with one sensor, 2 sensors, or thermostat Selectable priority (absolute / none) Selectable DHW heating program (according to DHW heating program / space heating programs, 24 hours) DHW push, manually or automatically Legionella function DHW discharge protection Control of DHW circulating pump Frost protection DHW ECO function Control of stratification storage tank Control of instantaneous DHW heater Aqua-booster system 14/18
Functions (cont d) General Automatic summer- / wintertime changeover Standard time programs Multifunctional inputs and outputs Connection facility for mixing valve module for 2nd mixing / pump circuit Connection facility for service tool (via OCI700 ) Connection facility for remote supervision (via OCI611...) Automatic sensor identification Input and output test Maintenance alarms and fault status messages Note: Some of the above functions are not available with the basic unit alone but only in connection with the respective extension modules! 15/18
Basic diagram Lockout (STB, TB) Safety shutdown (GP) or R BV1 BV2 Fuel valve Room thermostat 1 or time switch external ignition module Room thermostat 2 or time switch 4 modulated PWM fan Heating circuit pressure switch DHW FlowSwitch or DHW thermostat Programmable digital input e.g. for air pressure switch LMU74... PWM-moduliert Heating circuit pump DHW pump 1 or diverting valve Boiler flow sensor (tested) Programmable output Boiler flow sensor (tested) DHW sensor 1 or DHW thermostat 5 AGU2.5... ClipIn Water pressure sensor QAA55... QAA75... Outside sensor 2 / 3 Room controller HMI AVS37... Operator unit Reset button The diagram shows the full scope of functions offered by the LMU74 system. The actual functions are to be determined based on the respective execution / configuration. 16/18
Basic diagram (cont'd) Lockout (STB, TB) Safety shutdown (GP) or R BV1 BV2 Fuel valves Room thermostat 1 or time switch external ignition module Room thermostat 2 or time switch 4 modulated PWM fan Heating circuit pressure switch 6 Stepper motor control M (combustion optimization) DHW FlowSwitch or DHW thermostat Programmable digital input e.g. for air pressure switch Boiler flow sensor (tested) LMU75... Heating circuit pump DHW pump 1 or diverting valve Boiler return sensor (tested) Programmable output DHW sensor 1 or DHW thermostat 5 AGU2.5... ClipIn Water pressure sensor QAA55... QAA75... Outside sensor 2 / 3 Room controller HMI AVS37... Operator unit Reset button The diagram shows the full scope of functions offered by the LMU75 system. The actual functions are to be determined based on the respective execution / configuration. 17/18
Dimensions LMU7... Dimensions in mm 29 115 156 48,5 24 max. 47 162,75 145 O 3,5 (7 x) 7,5 67 73 115 137,5 11 59 156 170 7,5 7495m01/0805 18/18 2015 Siemens AG, Berliner Ring 23, D-76437 Rastatt Subject to change!