Type 8756 Table of contents TABLE OF CONTENTS 1 About this document.......................... 6 Manufacturer ............................ 6 Used symbols ........................... 6 Terms and abbreviations ........................ 7 2 Safety instructions............................ 8 Intended use ............................. 8 Safety.............................. 8 3 Product description.......................... 10 Design............................. 10 Product identification ........................ 12 3.2.1...
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Type 8756 Table of contents Safety instructions .......................... 35 Additional documentation ...................... 35 Wire the product variant büS /CANopen.................. 36 6.3.1 With büS extension cables from Bürkert ................ 36 6.3.2 With büS cables from Bürkert.................... 36 6.3.3 With CANopen cables...................... 37 Wire the product variant Analogue .................... 38 6.4.1...
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Type 8756 Table of contents Sterilising a product variant MFM with hot water................ 58 Sterilising a product variant MFM with steam ................ 58 10 Troubleshooting ............................ 60 10.1 Status indicator is red........................ 60 10.2 Status indicator is orange....................... 63 10.3 Status indicator is yellow........................ 63 10.4 Status indicator is blue ........................
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.
Type 8756 About this document Terms and abbreviations The terms and abbreviations are used in this document to refer to following definitions. Device / Product Type 8756 Mass Flow Meter Mass Flow Controller büS Bürkert system bus, a communication bus developed by Bürkert and based on the...
SAFETY INSTRUCTIONS Intended use The MFM Type 8756 is designed to measure the mass flow rate of liquids. The MFC Type 8756 is designed to measure and regulate the mass flow rate of liquids. The permitted media are listed in Technical data [} 17] Only trained and qualified personnel may install, operate and maintain the device.
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Type 8756 Safety instructions Have all other works carried out by Bürkert only. Electric shock due to electrical components Touching live parts can result in severe electric shock. This can lead to serious personal injury or death. Before working on the device or the system, switch off the power supply. Secure it against reactivation.
This manual describes following product variant: MFM büS/CANopen MFM Analogue The mass flow controller Type 8756 is particularly suitable for the very precise control of small quantities of liquid that also require a medium-separated sensor. This manual describes following product variant: MFC büS/CANopen with pump...
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Type 8756 Product description MFC with pump 8 9 10 Fig. 2: MFC with pump 1 Electrical connection 2 Electrical connection 3 Fluid connection 4 Functional earth connection 5 Base block 6 Pump 7 Not used 8 Not used 9 Not used...
9 Not used 10 Status indicator (LED) 11 Screw 12 Cover 13 büS-interface 14 Slot for the memory card Product identification 3.2.1 Type label Fig. 5: Example of type label Type 8756 1 Type of the product 2 Supply voltage, direct current...
Type 8756 Product description 3 Consumption according to UL 61010-1 4 Warning symbol: Observe the Operating In- [typical consumption] structions 5 Calibration fluid 6 Sealing material 7 Burst pressure 8 Manufacturing code 9 Product article number 10 Product serial number...
If product-specific data is stored on the inserted memory card, then the product adopts the data. At product delivery, the memory card contains product-specific data. To get a list of the stored data, refer to the file Device Description File that can be downloaded from country.burkert.com. Colour and diagnostics according to NE 107...
Type 8756 Product description If the inserted memory card is empty, then the product loads its own data on the memory card. A new memory card is empty. The data on the memory card can be transferred to another product with the same article number. For ex- ample, the data can be transferred from a defective product to a new product.
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Type 8756 Product description When selecting the actuator, observe the following basic data of the MFC for modular actuator: nominal flow rate inlet pressure...
Type 8756 Technical data TECHNICAL DATA Standards and Directives The device complies with the relevant 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.
Type 8756 Technical data MFC with proportional valve Ambient temperature 0 °C...+50 °C Fluid temperature –10 °C...+60 °C, only in liquid state Relative ambient humidity Max. 95% at 55 °C (non-condensing) Operating altitude Up to 2000 m above see level Degree of protection IP65 according to EN 60529 / IEC 60529 (only with cables, plugs or sockets connected correctly) determined by Bürkert, not evaluated...
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Type 8756 Technical data 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. Density measurement Density range 0...5 kg/l Measurement accuracy For mass flow rate values higher than 1.5 kg/h ±0.01 kg/l...
Type 8756 Technical data Repeatability DN1: ±0.1% of the measured value or ±0.7 g/h 0.7 g/h = zero-point stability DN2: ±0.05% of the measured value or ±7.5 g/h 7.5 g/h = zero-point stability Response time (t95%) < 750 ms The response time depends on the operating fluid used 2.500...
Type 8756 Technical data 4.3.3 MFC with pump Calibration conditions Calibration fluid Water Temperature of the calibration fluid 25 °C Calibration pressure 4 bar Operating fluid Operating fluid Liquids Type of liquids Liquids that are clean and homogeneous Maximum particle size 10 μm Minimum dynamic viscosity 0.3 mPa.s...
Type 8756 Technical data Settling time (t95%) < 1 s, for water at 20 °C The settling time depends on the operating fluid used. [kg/h] Nominal flow rate Q Fig. 10: Measurement range depending on nominal flow rate 4.3.4 Pressure loss - MFC with pump A MFC with pump has a pressure loss that depends on the operating fluid.
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Type 8756 Technical data Maximum dynamic viscosity 40 mPa.s, with reduced flow-rate range. Take the pressure loss into account. Refer to chapter Pressure loss. Maximum back pressure 50% of the inlet pressure Density measurement Density range 0...5 kg/l Measurement accuracy For mass flow rate values higher than 1.5 kg/h ±0.01 kg/l...
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Type 8756 Technical data Maximum particle size 10 μm Minimum dynamic viscosity 0.3 mPa.s Maximum dynamic viscosity 200 mPa.s Take the pressure loss into account. Refer to chapter Pressure loss. Density measurement Density range 0...5 kg/l Measurement accuracy For mass flow rate values higher than 1.5 kg/h ±0.01 kg/l...
Type 8756 Technical data Repeatability DN1: ±0.1% of the measured value or ±0.7 g/h 0.7 g/h = zero-point stability DN2: ±0.05% of the measured value or ±7.5 g/h 7.5 g/h = zero-point stability Response time (t95%) < 750 ms The response time depends on the operating fluid used 2.500...
Type 8756 Technical data Electrical data MFM Analogue Operating voltage 24 V DC ±10 % Maximum power consumption Relay output type Change-over relay with 1 normally closed contact (break contact) and 1 normally open contact (make contact). Both contacts are free of potential Maximum ratings 1 A, 30 V, 30 VA...
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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 - 0...5/10 V Resolution: 10 mV Analogue input for the measured Maximum input impedance: 200 Ω...
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Type 8756 Technical data Analogue output for the measured Maximum current: 20 mA value - 0...5/10 V Resolution: 10 mV Analogue input for the measured Maximum input impedance: 200 Ω value - 0/4...20 mA Resolution: 5 μA Analogue input for the measured Minimum input impedance: 20 kΩ...
Type 8756 Technical data Analogue input for the measured Minimum input impedance: 20 kΩ value - 0...5/10 V Resolution: 2,5 mV Digital input - 0...0.2 V to activate level 1 Digital input - 1...4 V or open to activate level 2 Digital input - 5...28 V...
Type 8756 Fluid connection FLUID CONNECTION Safety instructions DANGER! Risk of injury that is due to pressure in the installation or in the product. Before working on the installation or product, cut the pressure. Vent and drain the pipes. DANGER! Risk of injury from electric shocks.
Type 8756 Fluid connection NOTICE! Malfunction that is due to contamination. If a contaminated operating fluid is used, then install a filter upstream of the product. The filter ensures problem-free functioning of the product. Refer to chapter: Fluidic data [} 18] NOTICE! Malfunction that is due to the damage of the MFC pump.
Type 8756 Fluid connection Flow direction Risk of product malfunction due to bubble collection Fig. 16: Horizontal mounting positions Flow Flow direction direction Risk of product malfunction if the pipe runs dry Fig. 17: Vertical mounting positions 5.3.1 G1/8''-internal-threaded fluid connections Remove the protective cap that closes the threaded connection.
Type 8756 Fluid connection Do the fluid connection on the other side of the product in the same way. 5.3.4 Fluid connections with external-threaded compression fittings Do the fluid connection on one side of the product. Obey the instructions that are given by the manufacturer of the fitting used.
NEC Class 2 power supply unit 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 product, refer to the Operating Instructions "CAN- open Network configuration" at country.burkert.com.
With büS extension cables from Bürkert Requirements for the correct operation of the product. Refer to the cabling guide at country.burkert.com. To wire the product, use büS extension cables from Bürkert. Screw the mating female connector to the 5-pin male connector, to the torque given by the manufacturer of the mating female connector.
Type 8756 Electrical connection 5-pin M12 male connector (A Assignment coding) Shield 24 V CAN_H CAN_L M12 thread is internally con- Coding lug nected to FE Tab. 3: Pin assignment, 5-pin M12 male connector (A coding) Take a strand of the cable shielding and insert the strand into pin 1.
Type 8756 Electrical connection Do the functional earthing of the product. Connect the functional earth [} 41] Wire the product variant Analogue Requirements for the correct operation of the product. Use shielded CANopen cables. The cable shielding can be either a braid shielding or a foil shield- ing.
Type 8756 Electrical connection Screw the mating male connector to the 5-pin female connector, to the torque given by the manufacturer of the mating male connector. Do the functional earthing of the product. Refer to chapter: Connect the functional earth [} 41] Wire the mating female connector according to the pin assignment of the M12 male connector in the fol- lowing figure.
Type 8756 Electrical connection Available functions on MFC Reset the totaliser for the active fluid. Start the function autotune. Trigger the remote control of the actuator or trigger the control of the actuator by the product. Product Default assignment Reset totalizer Start autotune Tab. 9: Default assignment of the digital input...
Type 8756 Electrical connection Set-point value source has changed. Product Default assignment Empty pipe detected Gas bubbles in the system The set-point value cannot be reached Tab. 11: Default assignment of the relay output To choose the events that are assigned to the relay output, use the Bürkert Communicator software.
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Type 8756 Electrical connection 8-pin M12 female connector Assignment 24 V Not connected Not connected Not connected PWM (open collector) Internal use only Not connected Coding lug Housing Tab. 12: Pin assignment, 8-pin M12 female connector Screw the mating male connector to the 8-pin female connector, to the torque given by the manufacturer of the mating male connector.
Risk of injury that is due to the operating pressure. Make sure that the product operating-pressure is not higher than the operating pressure value on the product data-sheet. Refer to the data sheet on country.burkert.com. WARNING! Risk of injury from improper operation.
Type 8756 Commissioning Commissioning procedure (MFC with pump) If the pipes are empty and vented, and if the pump runs dry, then the pump of the MFC can be damaged. Set the set-point value to 0. Connect the product to the Bürkert Communicator software. Refer to chapter Connect the product to the Bürkert Communicator software [} 50]...
Type 8756 Commissioning If product-specific data is stored on the inserted memory card, then the product adopts the data. To get a list of the stored data at product delivery, refer to the Help for the Initiation file that can be downloaded from country.burkert.com.
Type 8756 Setting and operation SETTING AND OPERATION Safety instructions DANGER! Risk of injury that is due to pressure in the installation or in the product. Before working on the installation or product, cut the pressure. Vent and drain the pipes.
Type 8756 Setting and operation Functions 8.2.1 Empty-pipe detection To detect when the pipe is empty, the product monitors the density value of the liquid. If the density value is lower than 0.2 kg/l, then the pipe is empty and there is a warning with the following means: The product status indicator is yellow.
Type 8756 Setting and operation Connect the product to the Bürkert Communicator software. Refer to chapter: Connect the product to the Bürkert Communicator software In the Bürkert Communicator software, select the product. The product status indicator flashes. Go to Sensor >...
Type 8756 Setting and operation The product status indicator is orange. A check-function event is generated. Go to Actuator > Actuating variable Do the following sequence: set 100% > wait for 5 seconds > set 0% > wait for 5 seconds.
Type 8756 Setting and operation Connect the product to the Bürkert Communicator software 8.4.1 Product variant büS /CANopen To do the settings with the Type 8920 Bürkert Communicator software, do the following steps: Buy the USB-büS-interface set with article number 00772426 from Bürkert.
Type 8756 Setting and operation Click on in the Bürkert Communicator software to establish the communication between the Bürkert Communicator software and the product. A window opens. Select büS stick. Choose the port Bürkert USB büS Stick, click on Finish and wait until the product symbol appears in the list of devices.
Type 8756 Setting and operation Settings specific to the product variant büS/ CANopen 8.5.1 Set the CANopen communication or the büS communication To set the operating mode of the digital communication, do the following: Connect the product to the Bürkert Communicator software. Refer to chapter Connect the product to the Bürkert Communicator software [} 50]...
Type 8756 Setting and operation Operating modes of an MFC When energising the product for the first time, the product enters a short initialization phase and then switches to the normal operating mode. The normal operating mode is described in chapter: Normal oper- ating mode (MFC) [} 53]...
Type 8756 Setting and operation If the valve seat seal is made of a hard material such as PCTFE, then the control valve may not be tight. Products with a nominal valve diameter of 0.05 mm or 0.1 mm have a valve seat seal made of a hard material.
Type 8756 Setting and operation On a MFC with pump, fill the pipe as described in the chapter: Fill the pipe without damaging the pump (MFC with pump) [} 49] After applying the operating voltage, the product enters a short initialisation phase and then switches to the normal operating mode.
On a büS/CANopen product variant it is possible to alternatively change the related object. Refer to the re- lated procedure in the product-specific help in the documentation of the initiation files. Download the initi- ation files and the related documentation at country.burkert.com. The setting of the parameter...
Type 8756 Maintenance MAINTENANCE If no heavily contaminated fluids are used and if the product is operated according to the Operating instruc- tions, then the product is maintenance-free. Safety instructions DANGER! Risk of injury that is due to pressure in the installation or in the product.
Type 8756 Maintenance Replace the memory card To replace the memory card on the product, do the following: De-energise the product. With a TX8 screwdriver loosen the screws of the cover. Remove the cover. Screws Cover Memory card: make sure the insertion direction is correct.
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Type 8756 Maintenance Let steam at a temperature of 120°C flow through the product for 30 min. Let the product cool down for 2h. Commission the product.
Type 8756 Troubleshooting TROUBLESHOOTING 10.1 Status indicator is red MFM Analogue Cause Solution The supply voltage is out of the error Operate the product within the specifications. If the product range. The product can be damaged. status indicator is still red, then send the product back to Bürkert.
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Type 8756 Troubleshooting MFC Analogue with proportional valve Cause Solution The supply voltage is out of the error Operate the product within the specifications. If the product range. The product can be damaged. status indicator is still red, then send the product back to Bürkert.
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Type 8756 Troubleshooting MFC büS/CANopen with proportional valve Cause Solution The supply voltage is out of the error Operate the product within the specifications. If the product range. The product can be damaged. status indicator is still red, then send the product back to Bürkert.
Type 8756 Troubleshooting 10.2 Status indicator is orange MFM Analogue Cause Solution A calibration procedure is in progress. Wait until the calibration procedure is completed. MFM büS/CANopen Cause Solution The product is connected to büS and Wait until the product has found assigned fieldbus parti- searches assigned fieldbus participant.
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Type 8756 Troubleshooting MFM Analogue Cause Solution One of the following values is out of spe- Operate the product within the specifications. If the product cification. The sensor or the product can status indicator is still yellow, then send the product back to be damaged.
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Type 8756 Troubleshooting Cause Solution The product has detected bubbles in the Flush bubbles from the pipe as described in chapter: Flush liquid. bubbles from the pipe (MFC with pump) [} 48] The set-point position for the actuator Decrease the back pressure.
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Type 8756 Troubleshooting Cause Solution The product has detected bubbles in the If the connected actuator is a proportional valve, then flush liquid. bubbles from the pipe as described in chapter: Flush bubbles from the pipe (MFC with proportional valve) [} 48]...
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Type 8756 Troubleshooting MFC büS/CANopen with proportional valve Cause Solution One of the following values is out of spe- Operate the product within the specifications. If the product cification. The sensor or the product can status indicator is still yellow, then send the product back to be damaged.
Type 8756 Troubleshooting Cause Solution The set-point position for the actuator Decrease the back pressure. has (almost) reached 100%. The set- Make sure that the fluid viscosity is in the permitted range. point value cannot be reached. Refer to table: Operating fluid, MFC for modular actuator If the pressure drop in the pipe is too high, then reduce the pressure drop.
Type 8756 Troubleshooting 10.8 Replacement product adopts none of the values from the defective product Cause Solution The article number of the replacement Use a replacement product that has the same article num- product is different from the article num- ber than the defective product.
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.
Type 8756 Troubleshooting MFC for modular actuator 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.
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Type 8756 Troubleshooting Cause Solution The operating pressure is above the tight Reduce the operating pressure. sealing pressure of the control valve. To eliminate the defect, return the product to the manufac- turer. MFC Analogue for modular actuator Cause Solution The operating mode of the product is set Either set the MFC to the normal operating mode.
Type 8756 Troubleshooting Cause Solution The connected actuator is a pump and Install the fluid container in such a way that no pressure is there is pressure upstream the pump. generated upstream the pump. The pressure makes the fluid flow. Pres- sure can be due to an incorrect position of the fluid container.
Type 8756 Troubleshooting Cause Solution The inlet pressure is too low. Make sure that the pipe diameters and the pipe lengths are adapted. Refer to Pressure loss - MFC with proportional valve [} 24] The back pressure is too high. Make sure that the pipe diameters and the pipe lengths are adapted.
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Type 8756 Troubleshooting MFC for modular actuator Cause Solution The pressurized liquid has a high gas sol- If possible, reduce the liquid pressure. ubility or outgassing occurs due to the Pressurize with a gas that has a lower solubility in the fluid.
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.
Type 8756 Spare parts and accessories Item Article number Connection cable with M12 female connector (A-coded) and free cable 563108 end, 10 m Memory card On request Tab. 17: Electrical accessories, product variant Analogue For further accessories, refer to the product data sheet. Cable assemblies can be made on request.
Type 8756 Uninstallation UNINSTALLATION 12.1 Safety instructions DANGER! Risk of injury that is due to pressure in the installation or in the product. Before working on the installation or product, cut the pressure. Vent and drain the pipes. DANGER! Risk of injury from electric shocks.
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Type 8756 Uninstallation Fluid connections Fig. 26: Fluid connections, for example internal-threaded connections Remove the product.
Type 8756 Logistic LOGISTIC 13.1 Transport NOTICE! Transport damage. If the product is not protected in transport, then the product can be damaged. Remove cables, connectors, product-external filters and installation equipment. Protect the electrical interfaces with protective plugs. Clean and vent contaminated products.
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