Burkert 8756 Operating Instructions Manual
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Burkert 8756 Operating Instructions Manual

Mass flow meter / mass flow controller for liquids
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Type 8756
Mass flow meter / Mass flow controller for liquids
Operating Instructions

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Summary of Contents for Burkert 8756

  • Page 1 Type 8756 Mass flow meter / Mass flow controller for liquids Operating Instructions...
  • Page 2 We reserve the right to make technical changes without notice. © Bürkert Werke GmbH & Co. KG, 2020 - 2024 Operating Instructions 2402/04 00573797 / Original EN...

  • Page 3: Table Of Contents

    Type 8756 Table of contents TABLE OF CONTENTS 1 About this document.......................... 6 Manufacturer............................. 6 Symbols ............................ 6 Terms and abbreviations ........................ 7 2 Safety ................................ 8 Intended use ............................. 8 Safety instructions .......................... 8 3 Product description .......................... 11 Product overview .......................... 12 Product identification ........................ 16 3.2.1 Type label .......................... 16 3.2.2...
  • Page 4 Type 8756 Table of contents 5 Medium connection .......................... 40 Possible medium connections ...................... 40 Installation procedure ........................ 40 5.2.1 G1/8''-internal-threaded connections ................ 42 5.2.2 NPT1/8''-internal-threaded connections ................ 42 5.2.3 Connections with external-threaded vacuum fittings ............ 42 5.2.4 Connections with external-threaded compression fittings.......... 42 5.2.5 Tri-clamp connections ....................... 42 6 Electrical connection.......................... 44...
  • Page 5 Type 8756 Table of contents 8.10 Set-point values without communication .................. 66 8.11 Changing between büS and CANopen mode................. 66 9 Maintenance ............................. 67 Replace the memory card....................... 67 Sterilising the device with hot water .................... 68 Sterilising the device with steam .................... 68 10 Troubleshooting ............................ 69 10.1 Status indicator is red ........................ 69...

  • Page 6: About This Document

    Before starting any work on the product, read and observe the respective sections of the document. Keep the document available for reference and give it to the next user. Contact the Bürkert sales office for any questions. Further information concerning the product at country.burkert.com. Manufacturer Bürkert Fluid Control Systems Christian-Bürkert-Str.

  • Page 7: Terms And Abbreviations

    Type 8756 About this document Terms and abbreviations The terms and abbreviations are used in this document to refer to following definitions. Device Type 8756 Mass flow meter Mass flow controller büS Bürkert system bus, a communication bus developed by Bürkert and based on the...

  • Page 8: Safety

    Type 8756 Safety SAFETY Intended use The device MFM is designed to measure the mass flow rate of liquids. The device MFC is designed to measure and regulate the mass flow rate of liquids. The permitted media are listed in Technical data [} 21].
  • Page 9 Type 8756 Safety Electrostatically sensitive components and assemblies The device contains electronic components that are susceptible to the effects of electrostatic discharging (ESD). Components that come into contact with electrostatically charged persons or objects are at risk. In the worst case scenario, these components will be destroyed immediately or fail after start-up.
  • Page 10 Type 8756 Safety Only feed media into the media ports that are listed in the chapter Technical data [} 21]. Observe the safety data sheet for the media used. Only use authorised devices in a potentially explosive atmosphere There are variants for this device type that may be used in Ex areas. These variants are identified by a sep- arate Ex type label.

  • Page 11: Product Description

    Type 8756 Product description PRODUCT DESCRIPTION The device is used for ultimate precision in the feedback control of medium. This document describes following variant: MFM Analogue MFM büS/CANopen MFM Industrial Ethernet MFC Analogue with pump MFC Analogue with proportional valve MFC Analogue with an interface for a modular actuator MFC büS/CANopen with pump...

  • Page 12: Product Overview

    Type 8756 Product description Product overview 1. Screw 2. Cover 3. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Status indicator - ETH port 1 4. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Communication indicator 5. Analogue: Not used büS/CANopen: Not used...
  • Page 13 Type 8756 Product description MFC with pump 1. Screw 2. Cover 3. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Status indicator - ETH port 1 4. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Communication indicator 5. Analogue: Not used büS/CANopen: Not used...
  • Page 14 Type 8756 Product description MFC with proportional valve 1. Screw 2. Cover 3. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Status indicator - ETH port 1 4. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Communication indicator 5. Analogue: Not used büS/CANopen: Not used...
  • Page 15 Type 8756 Product description MFC for modular actuator 1. Screw 2. Cover 3. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Status indicator - ETH port 1 4. Analogue: Not used büS/CANopen: Not used Industrial Ethernet: Communication indicator 5. Analogue: Not used büS/CANopen: Not used...

  • Page 16: Product Identification

    Type 8756 Product description Product identification 3.2.1 Type label Fig. 1: Example of type label Type 8756 1 Type 2 Operating voltage 3 Power consumption 4 Note: Observe the operating instructions 5 Calibration medium 6 Bürkert internal version 7 Sealing material...

  • Page 17: Conformity Marking

    Type 8756 Product description 3.2.3 Conformity marking Fig. 3: Conformity label 1 CE marking 2 Certification marking for USA and/or Canada 3 Warning: hot surface 4 Indication for disposal 3.2.4 Symbols and markings on device Earth terminal Direct current Industrial Ethernet variant...

  • Page 18: Network Status Indicator

    Type 8756 Product description Colour Colour Status Description code Failure, error or fault Due to a malfunction in the device or its periphery, normal operation is not possible. orange Function check Work is being carried out on the device, which means that normal operation is temporarily not possible.

  • Page 19: Functionality

    Type 8756 Product description Functionality 3.4.1 Service-büS interface Analogue variant Industrial Ethernet variant The Service-büS interface is used for short-term servicing of the device with the Bürkert Communicator. The Bürkert Communicator runs under Windows. Refer to Connect to the Bürkert Communicator [} 56] The USB-büS-Interface set, available as an accessory, is necessary.

  • Page 20: Actuator Is A Control Valve

    To get a list of the stored data, refer to the file Device Description File that can be downloaded from country.burkert.com. If the inserted memory card is empty, then the device loads its own data on the memory card. A new memory card is empty.

  • Page 21: Technical Data

    Type 8756 Technical data TECHNICAL DATA Standards and directives The device complies with the valid EU harmonisation legislation. In addition, the device also complies with the requirements of the laws of the United Kingdom. The harmonised standards that have been applied for the conformity assessment procedure are listed in the current version of the EU Declaration of Conformity/UK Declaration of Conformity.
  • Page 22 Type 8756 Technical data Altitude Up to 2000 m above sea level Medium temperature −10…+60 °C, only in liquid state Medium Clean and homogeneous liquids Operating pressure (inlet pressure) 0 bar Operating pressure (outlet pressure) max. 10 bar Relative ambient humidity Max. 95% at 55 °C (non-condensing)

  • Page 23: Medium Data

    Type 8756 Technical data Operating pressure External-threaded compression fittings max. 50 bar Relative ambient humidity Max. 95% at 55 °C (non-condensing) Medium data 4.3.1 Calibration conditions Calibration medium Water Temperature of the calibration me- 25 °C dium Calibration pressure 4 bar Operating medium Maximum particle size 10 μm...
  • Page 24 Type 8756 Technical data Minimum measurable mass flow DN1: factory setting 0.05 kg/h (can be reduced to 0.01 kg/h) rate DN2: factory setting 0.25 kg/h (can be reduced to 0.05 kg/h) Measurement accuracy after DN1: ±0.1% of the measured value or ±1.4 g/h. 1 minute warm-up time 1.4 g/h = zero-point stability...

  • Page 25: Pressure Loss - Mfm

    Type 8756 Technical data 4.3.2 Pressure loss - MFM A MFM has a pressure loss that depends on the following parameters: the flow-rate value the size of the medium connections the type of the medium connections the size of the device base block...
  • Page 26 Type 8756 Technical data Operating medium Maximum particle size 10 μm Minimum dynamic viscosity 0.3 mPa.s Maximum dynamic viscosity 200 mPa.s, with reduced flow-rate range. If the flow rate is equal to 8 kg/h, then the medium viscosity must be max. 50 mPa.s. Take the pressure loss into account. Refer to chapter Pressure loss.

  • Page 27: Pressure Loss - Mfc With Pump

    Type 8756 Technical data 4.3.4 Pressure loss - MFC with pump A MFC with pump has a pressure loss that depends on the medium. ∆p [bar] Outlet pressure Outlet pressure Inlet pressure of the device of the pump of the pump Fig. 11: Pressure loss diagram for water at 20 °C through an MFC with pump...

  • Page 28: Pressure Loss - Mfc With Proportional Valve

    Type 8756 Technical data Mass flow rate measurement Mass flow rate range Factory setting: 25 kg/h Minimum reducible to 4 kg/h Control accuracy after 1 minute ±0.5% of the measured value OR ±0.012 kg/h. Take the highest warm-up time value into account. Maximum measurement range > 1:300...

  • Page 29: Mfc For Modular Actuator

    Type 8756 Technical data 4.3.7 MFC for modular actuator Calibration conditions Calibration medium Water Temperature of the calibration me- 25 °C dium Calibration pressure 4 bar Operating medium Maximum particle size 10 μm Minimum dynamic viscosity 0.3 mPa.s Maximum dynamic viscosity 1500 mPa.s Take the pressure loss into account. Refer to chapter Pressure loss.

  • Page 30: Pressure Loss - Mfc For Modular Actuator

    Type 8756 Technical data Measurement accuracy after DN1: ±0.1% of the measured value or ±1.4 g/h. 1 minute warm-up time 1.4 g/h = zero-point stability DN2: ±0.1% of the measured value or ±10 g/h. 10 g/h = zero-point stability Maximum measurement range 1:3000 The measurement range is defined as the ratio of Qnominal of the device to Qmin.

  • Page 31: Electrical Data

    Type 8756 Technical data the flow-rate value the size of the medium connections the type of the medium connections the size of the device base block the type of medium the actuator Mass flow [kg/h] Fig. 16: Pressure loss diagram for DN1 Mass flow [kg/h] Fig. 17: Pressure loss diagram for DN2...
  • Page 32 Type 8756 Technical data Analogue output for the measured Maximum loop impedance: 600 Ω at an operating voltage of 24 V value 0/4...20 mA Resolution: 20 μA Analogue output for the measured Maximum current: 20 mA value Resolution: 10 mV 0...5/10 V Digital input to activate level 1 0...0.2 V...
  • Page 33 Type 8756 Technical data Minimum temperature rating of the 75 °C cable to be connected to the field wiring terminals: MFC Analogue with pump Operating voltage 24 V DC ±10 % residual ripple < 2 % Power consumption < 67 W Typical power consumption 16 W for water and at a flow rate of 8 kg/h Analogue input for the measured Maximum input impedance: 200 Ω...
  • Page 34 Type 8756 Technical data Power consumption < 67 W Typical power consumption 16 W for water and at a flow rate of 8 kg/h Communication interface Industrial Ethernet: PROFINET, EtherNet/IP, EtherCAT, Modbus TCP Electrical connections M12 plug 5-pin A-coding 2 M8 socket 4-pin D-coding service büS interface...
  • Page 35 Type 8756 Technical data Digital input to activate level 1 0...0.2 V Digital input to activate level 2 1...4 V or open Digital input to activate level 3 5...28 V Relay output type Change-over relay with 1 normally closed contact (break contact) and 1 normally open contact (make contact). Both contacts are free...
  • Page 36 Type 8756 Technical data Minimum temperature rating of the 75 °C cable to be connected to the field wiring terminals: MFC Analogue for modular actuator Operating voltage 24 V DC ±10 % Power consumption < 2 W PLUS < 30 W (power consumption of the actuator) PWM signal (actuator output) Open collector, 22 kΩ-pull-up resistor and free wheeling diode, both...

  • Page 37: Mechanical Data

    Type 8756 Technical data MFC Industrial Ethernet for modular actuator Operating voltage 24 V DC ±10 % Power consumption < 2 W PLUS < 30 W (power consumption of the actuator) PWM signal (actuator output) Open collector, 22 kΩ-pull-up resistor and free wheeling diode, both to 24 V Analog output (actuator output) 0-10 V analog signal...

  • Page 38: Communication

    Type 8756 Technical data MFM Alloy C22 Base block Alloy C22 Parts in contact with the medium Alloy C22 (sensor) MFC with proportional valve Parts in contact with the medium Stainless steel 303, stainless steel 434, stainless steel 301 The material depends on the equipped proportional valve Communication 4.6.1...

  • Page 39: Industrial Ethernet: Modbus Tcp

    Type 8756 Technical data MDI modes MDI, MDI-X, Auto-MDI-X Data transport layer Ethernet II, IEEE 802.3 Address Conflict Detection (ACD) supported DLR (ring topology) supported CIP reset service Identity Object Reset Service Type 0 and Type 1 4.6.3 Industrial Ethernet: Modbus TCP...

  • Page 40: Medium Connection

    Type 8756 Medium connection MEDIUM CONNECTION Risk of injury or material damage when working on the device or system. Read and observe the chapter Safety [} 8] before working on the device or system. Possible medium connections G-internal-threaded connections according to DIN ISO228/1 NPT-internal-threaded connections according to ASME/ ANSI B 1.20.1...
  • Page 41 Type 8756 Medium connection CAUTION! Risk of injury that is due to leakage in an MFC with proportional valve. Use pipes with a diameter that is adapted to the medium connection of the device, and with a smooth surface. NOTICE! Malfunction that is due to contamination.

  • Page 42: G1/8''-Internal-Threaded Connections

    Type 8756 Medium connection Flow Flow direction direction Risk of device malfunction if the pipe runs dry Fig. 19: Vertical mounting positions 5.2.1 G1/8''-internal-threaded connections Remove the protective cap that closes the threaded connection. Do the medium connection on one side of the device.
  • Page 43 Type 8756 Medium connection Do the medium connection on one side of the device. Obey the instructions that are given by the manufacturer of the fitting used. Do the medium connection on the other side of the device in the same way.

  • Page 44: Electrical Connection

    Additional documentation For more information on büS, read the cabling guide that is available at country.burkert.com. For more information on CANopen that is related to the device, refer to the Operating Instructions "CAN- open Network configuration"...

  • Page 45: With Canopen Cables

    Type 8756 Electrical connection Colour of the büS cable conductor Signal 24 V DC black white CAN_H blue CAN_L Tab. 3: Signals of the büS cable conductors NOTICE! If an own mating female connector is used, then observe the following requirements for the correct op- eration of the device.

  • Page 46: Wire The Variant Analogue

    Type 8756 Electrical connection NOTICE! Requirements for the correct operation of the device. Use a mating female connector with shield connection. Observe the specifications for the cable and conductors, that are given by the manufacturer of the mat- ing female connector.
  • Page 47 Type 8756 Electrical connection NOTICE! UL approved versions must be supplied in one of the following ways: "Limited Energy Circuit" (LEC), according to UL / IEC61010-1 "Limited Power Source" (LPS), according to UL / IEC60950 SELV / PELV with UL-approved overcurrent protection, designed according to UL / IEC61010-1, Table 18 (e.g.

  • Page 48: Digital Input

    Type 8756 Electrical connection 5-pin M12 male connector Assignment GND for the analogue output and the set-point input 24 V Set-point input Analogue output for the measured value M12 thread is internally con- Coding lug nected to FE Tab. 8: Pin assignment, 5-pin M12 male connector (A coding) Connect the cable shielding to the mating female connector.

  • Page 49: Relay Output

    Type 8756 Electrical connection Device Default assignment Start autotune Tab. 10: Default assignment of the digital input To choose the function to be remotely triggered over the digital input, use the Bürkert Communicator software. Only one of the available functions can be associated to the digital input.

  • Page 50: Wire The Variant Industrial Ethernet

    Type 8756 Electrical connection Device Default assignment The set-point value cannot be reached Tab. 12: Default assignment of the relay output To choose the events that are assigned to the relay output, use the Bürkert Communicator software. Several events can be associated to the relay output.

  • Page 51: Change The Network Parameters

    Type 8756 Electrical connection 4-pin M8 female connector (D Assignment coding) Tx + Rx + Tx − Rx − Coding lug M8 thread is internally connec- ted to FE Tab. 14: Pin assignment, 4-pin M8 If a protocol other than EtherCAT is used, plug an Ethernet cable in one or both sockets.

  • Page 52: Over The Bürkert Communicator Software

    Type 8756 Electrical connection Open the web browser. In the address bar of the web browser, enter 192.168.1.100. The home page of the web server opens. Some device data are shown. Open a web server session, to configure the network parameters of the device.

  • Page 53: Connect The External Actuator

    Type 8756 Electrical connection Attach the green-and-yellow cable to the M4 screw with a cable lug. Tighten the M4 screw to a torque of 1,8 N·m...2 N·m (1,33 lbf·ft...1,47 lbf·ft). Connect the external actuator MFC for modular actuator To wire the device, mating male connectors are available from Bürkert.

  • Page 54: Commissioning

    Type 8756 Commissioning COMMISSIONING Risk of injury or material damage when working on the device or system. Read and observe the chapter Safety [} 8] before working on the device or system. Commissioning procedure The operation of the device is tested at the factory with medium. Residual medium can remain in the device.

  • Page 55: Fill The Pipe Without Damaging The Pump

    Type 8756 Commissioning Check if the memory card is inserted. Energise the device. Variant büS /CANopen: Choose between CANopen communication and büS communication. Refer to Set the CANopen communication or the büS communication [} 60] Run the Autotune function. Refer to Optimise the closed-loop control parameters [} 64]...

  • Page 56: Configuration With Bürkert Communicator

    Industrial Ethernet variant Use the USB-büS-Interface set with article number 00772551. Download the latest version of the Type 8920 Bürkert Communicator from country.burkert.com. Install the Bürkert Communicator on a PC. During installation, the büS stick must not be inserted at the Assemble the parts of the USB-büS-Interface set.
  • Page 57 Fig. 22: USB-büS-Interface set Download the latest version of the Type 8920 Bürkert Communicator from country.burkert.com. Install the Bürkert Communicator on a PC. During installation, the büS stick must not be inserted at the micro-USB connector...

  • Page 58: Functions

    Type 8756 Configuration with Bürkert Communicator Click on in the Bürkert Communicator to establish the communication with the device. A window opens. Select Connect via USB (büs Stick). Choose the port Bürkert USB büS stick, click on Finish and wait until the device symbol appears in the list of devices.

  • Page 59: Flush Bubbles From The Pipe

    Type 8756 Configuration with Bürkert Communicator Cut-off limit Default value DN1: 0.05 kg/h DN2: 0.25 kg/h MFC with pump 0.05 kg/h MFC with proportional valve 0.02 kg/h MFC for modular actuator DN1: 0.05 kg/h DN2: 0.25 kg/h Set the cut-off limit with the Bürkert Communicator software: Connect the device to the Bürkert Communicator software.

  • Page 60: Configure The Actuator

    Type 8756 Configuration with Bürkert Communicator Connect the device to the Bürkert Communicator software. Refer to Connect to the Bürkert Communic- ator [} 56] In the Bürkert Communicator software, select the device. WARNING! Risk of injury from flowing medium. While the procedure is running, the mass flow rate value can be higher than the nominal flow rate value.

  • Page 61: Increase The Data Transmission Speed

    Type 8756 Configuration with Bürkert Communicator If the operating mode of the fieldbus is büS, then the CANopen status is set to Operational and the PDOs are sent to büS. If the operating mode of the fieldbus is CANopen, then the...

  • Page 62: Normal Operation Mode

    Type 8756 Configuration with Bürkert Communicator Operating mode Refer to Manual set-point value Choose the source that gives the set-point value [} 65] Stored set-point value Choose the source that gives the set-point value [} 65] Open-loop control mode Choose the source that gives the set-point value [} 65] Analyze system Choose the source that gives the set-point value [} 65]...

  • Page 63: Analogue Variant

    Type 8756 Configuration with Bürkert Communicator xout xd = w-x Fig. 25: Function diagram of the MFC with control valve 1 Medium inlet 2 Sensor 3 Control valve 4 Medium outlet 5 Electronics x measured value of the mass flow rate...

  • Page 64: Industrial Ethernet Variant

    Type 8756 Configuration with Bürkert Communicator Analogue output range Minimum value of the input ranges Maximum value of the input and output ranges ranges and output ranges 0...5 V 0 V, w = 0% 5 V, w = 100% 0...10 V...

  • Page 65: Choose The Source That Gives The Set-Point Value

    Download the initiation files and the related documentation at country.burkert.com. On a Industrial Ethernet variant it is possible to alternatively change the related object. Refer to the related procedure in the device-specific help in the documentation of the initiation files.

  • Page 66: Set-Point Values Without Communication

    Type 8756 Configuration with Bürkert Communicator 8.10 Set-point values without communication Industrial Ethernet variant büS / CANopen variant The function makes it possible to specify the set-point values of an MFC even if the communication with the external set-point value provider (for example a PLC) is broken. If the function is used, then the set-point is kept constant.

  • Page 67: Maintenance

    Troubleshooting [} 69] büS / CANopen variant The büS/CANopen variant supports the config-client if no memory card is used. For detailed information, refer to the Operating Instructions "Central configuration management of Bürkert devices" that can be downloaded from country.burkert.com.

  • Page 68: Sterilising The Device With Hot Water

    Type 8756 Maintenance Sterilising the device with hot water The sterilisation procedure is only valid for an MFM with seals in metal or FFKM. De-energise the device. Let water at a temperature of 90°C flow through the device for maximum 30 minutes.

  • Page 69: Troubleshooting

    Type 8756 Troubleshooting TROUBLESHOOTING 10.1 Status indicator is red MFM Analogue Cause Solution The supply voltage is out of the error Operate the device within the specifications. If the status in- range. The device can be damaged. dicator is still red, then send the device back to Bürkert.
  • Page 70 Type 8756 Troubleshooting MFC Analogue Cause Solution The supply voltage is out of the error Operate the device within the specifications. If the status in- range. The device can be damaged. dicator is still red, then send the device back to Bürkert.

  • Page 71: Status Indicator Is Orange

    Type 8756 Troubleshooting Cause Solution The device is connected to büS, but does Make sure that the process value is correctly allocated. not find the process value to be pro- Check the assigned büS participant that is defective. cessed. Make sure that the assigned büS participant provides the cyclic data.

  • Page 72: Status Indicator Is Yellow

    Type 8756 Troubleshooting Cause Solution The operation mode of the device is set Refer to Choose the source that gives the set-point value Open-loop control mode, Manual set- [} 65] point value Analyze system. PROFINET: PLC is in Stop mode Activate the PLC.
  • Page 73 Type 8756 Troubleshooting MFM Industrial Ethernet Cause Solution One of the following values is out of spe- Operate the device within the specifications. If the status in- cification. The sensor or the device can dicator is still yellow, then send the device back to Bürkert.
  • Page 74 Type 8756 Troubleshooting MFC Analogue Cause Solution One of the following values is out of spe- Operate the device within the specifications. If the status in- cification. The sensor or the device can dicator is still yellow, then send the device back to Bürkert.

  • Page 75: Status Indicator Is Blue

    Type 8756 Troubleshooting Cause Solution The set-point position for the actuator Increase the inlet pressure or decrease the output pressure. has (almost) reached 100%. The set- Make sure that the medium viscosity is in the permitted point value cannot be reached.

  • Page 76: Status Indicator Is Off

    Type 8756 Troubleshooting 10.5 Status indicator is off Cause Solution The device is not energised. Make sure that the device is correctly wired. Make sure that the voltage supply is 24 V DC. Make sure that the power supply source is working prop- erly.

  • Page 77: Replacement Device Does Not Adopt All Of The Values From The Defective Device

    Type 8756 Troubleshooting 10.9 Replacement device does not adopt all of the values from the defective device Cause Solution The device description of the replace- Use the Bürkert Communicator to configure the new values ment device is different from the device of the replacement device.

  • Page 78: Unstable Measured Value

    Type 8756 Troubleshooting 10.11 Unstable measured value Cause Solution Functional earth (FE) is not connected To connect the functional earth, use a green-and-yellow properly. cable that is as short as possible. And the cable cross-sec- tion must be at least equal to the cross section of the power-supply cable.

  • Page 79: Set-Point Value At 0 %, No Mass Flow, But A Non-Zero Mass Flow Rate Is Measured

    Type 8756 Troubleshooting The operating pressure is above the tight sealing Reduce the operating pressure. pressure of the control valve. To eliminate the defect, return the device to the manufacturer. The connected actuator is a proportional valve and Reduce the operating pressure.

  • Page 80: Set-Point Value Is Not Reached

    Type 8756 Troubleshooting Cause Solution There are bubbles in the sensor. The re- Flush the device to remove the bubbles. Refer to Flush lay output of an Analogue variant can be bubbles from the pipe (MFC) parametered to switch when there are bubbles in the sensor.

  • Page 81: Outgassing Or Bubble Formation At The Device Outlet

    Type 8756 Troubleshooting Cause Solution The connected actuator is a proportional Make sure that the pipe diameters and the pipe lengths are valve and the inlet pressure is too low. adapted. The connected actuator is a proportional Make sure that the pipe diameters and the pipe lengths are valve and the outlet pressure is too high.
  • Page 82 Type 8756 Troubleshooting LED indicator Meaning Action Link/Act-LED (green) slow blinking No connection to the parent pro- Check the cable. (20 s after restart) tocol layer. Link/Act-LED (green) is OFF. No connection to the network. Check the cable. Link-LED (yellow) is ON Connection to the network is es- tablished.

  • Page 83: Spare Parts And Accessories

    Type 8756 Spare parts and accessories SPARE PARTS AND ACCESSORIES CAUTION! Risk of injury, property damage due to incorrect parts. Incorrect options and unsuitable spare parts can cause injuries to people and damage to the appliance and its surroundings. Only use original options and original spare parts from Bürkert.

  • Page 84: Mounting Accessories

    Type 8756 Spare parts and accessories Item Article number Bent 8-pin M12 male connector 775 070 büS / CANopen variant Item Article number USB-büS-interface set, including power supply 772 426 Straight 5-pin M12 female connector 772 416 Bent 5-pin M12 female connector...

  • Page 85: Uninstallation

    Type 8756 Uninstallation UNINSTALLATION 12.1 Dismantling Relieve the medium pressure in the installation. Flush the device with distilled water. Relieve the flushing medium pressure in the installation. De-energise the device. Remove the mating female connectors and the mating male connectors.

  • Page 86: Logistics

    Type 8756 Logistics LOGISTICS 13.1 Transport and storage Protect the device against moisture and dirt in the original packaging during transportation and storage. Avoid UV radiation and direct sunlight. Protect connections from damage with protective caps. Observe permitted storage temperature.

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