4.1 Functional diagram FM100 fume hood monitor... 4 Functional description FM Interfaces Terminal diagram FM100...

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1 2.0 LabSystem Fume hood monitors Table of contents Section Title Page 1.1 Introduction Functional description Actual value and switching threshold Acoustic and optical alarm Two different measurement types Static differential pressure transmitter Dynamic sensor, air flow sensor Functional diagram FM100 fume hood monitor Functional description FM Interfaces Schematic diagram Power supply CPU set-up Two independent watchdog circuits Terminal diagram FM Function display and control panel Measuring devices for volume flow Performance features fume hood monitor Performance features FM Performance features FM Performance features im Product overview

2 1.1 Introduction The SCHNEIDER FM100, FM500 and im50 monitoring systems are designed for the functional monitoring of ventilation in fume hoods and extraction systems. Suitable for all constructions A monitoring system is mandatory for all fume hoods in accordance with DIN EN The FM100, FM500 and im50 fume hood monitors are suitable for fitting in all fume hood models and constructions and are thus ideally suited for retrofitting. Standards-compliant requirements Figure 2.1: FM100 fume hood controller The standards-compliant requirements for fume hood monitoring appliances are: Perfect functioning of the ventilation in all fume hoods must be monitored with an appliance that functions automatically and operates with a secure power supply (e.g. back-up battery). In the case of errors, an optical and acoustic alarm must be activated. It must not be possible to deactivate the optical signalling device (DIN 12924, part 1 and EN 14175). All SCHNEIDER monitoring systems fulfil these requirements. Additional configurations for all areas of application The FM100 monitoring system is available in various configurations, whereby monitoring is always fully compliant with the DIN EN standard. Safety in the laboratory Safe operation of the laboratory makes high demands on the monitoring components: Monitoring with optical and acoustic alarm when the minimum air volume is underrun, in accordance with DIN EN Monitoring and malfunction notification of the internal device functions and the sensor Volume flow measurement in exhaust air outlets, therefore independent of the construction and model of the sash or the fume hood All system parameters are saved mains voltage failuresafe (in the EEPROM) Monitoring of reduced operation (night-time operation) Recognition and optical alarm in the case of a mains voltage failure (operating LED flashes) Relay outputs with potential-free contacts for external signalling of malfunction and operating notifications Standards SCHNEIDER monitoring systems fulfil all European and American standards, such as the British Standard, DIN, DIN EN, Norm Francaise, ASHRAE, etc. 2.1 Functional description The SCHNEIDER FM100 monitoring system controls proper functioning of the ventilation in fume hoods or extraction systems Actual value and switching threshold The actual value of the volume flow is measured in the exhaust air outlet at regular intervals. After internal linearisation of the actual value, an arithmetic mean value is calculated. This ensures accurate analysis, since disturbance variables, such as air turbulence, are eliminated to a very large degree. The linearised actual value is now constantly compared with a freely programmable setpoint volume flow. 2

3 2.1.2 Acoustic and optical malfunction alarm If the measured exhaust air volume flow (actual value) is less than the setpoint volume flow for longer than the preset minimum malfunction period (standard value = 10 sec.), an acoustic and optical alarm is activated. The red LED on the function display lights up and the piezo buzzer signals the malfunction. The acoustic alarm can be acknowledged with the in-built RESET button. If the threshold value of a second switching threshold is exceeded, the air volume is too high. This condition is signalled by a yellow LED (optional). This signal is to be considered as a warning, because in certain conditions, an exhaust air volume flow that is too high can lead to the escape of contaminants. Okay Fault Okay Overflow green red green yellow Actual value oberer Grenzwert unterer Grenzwert Mains voltage failure, i.e. operation via a back-up battery, is signalled for example by a flashing operating or alarm LED. Figure 2.2: Functional diagram FM100 Time 3.1 Two different measurement types The ventilation function of a fume hood can be monitored with one of two different measurement methods: Measurement of volume flow with a static differential pressure sensor Recording of a face velocity speed with an air flow sensor Static differential pressure sensor A static differential pressure sensor either measures via a measuring device in the exhaust air pipe or measures negative pressure in the exhaust air pipe against the room pressure and provides a constant measurement signal, independent of the volume flow. The measuring principle of the differential pressure sensor works with a membrane which, according to the differential pressure Δp that is present, acts on a bending beam. The displacement of the bending beam is the direct measure of the differential pressure that is present Dynamic sensor, air flow sensor Monitoring of a face velocity speed in the front area of the fume hood is done with an air flow sensor. Measurement takes place in the bypass, i.e. an air flow sensor mounted in the fume hood roof measures the speed of the air flowing into the fume hood, which corresponds to the speed of the air flow in the sash area. The dynamic sensor operates in accordance with the calorimetric measuring principle. A thermal element is heated to a specific temperature, which, depending on the air speed, is cooled more or less by the air that flows by. The difference between the heating and cooling value is the direct measure of the speed of the air that flows by. Advantages and disadvantages of the various measurement types Measurement with a static differential pressure sensor is generally more precise and more robust with regard to disturbance variables. Due to the membrane measuring principle, the sensor is not permeated by the air that is to be measured and is therefore very resistant to contaminants in the air. However, sufficient inflow and outflow of air on the measuring tube must be ensured. The best measurement results are achieved with a SCHNEIDER M-xxx maintenance-free measuring device. In this case, inflow and outflow routes are not necessary. The air flow sensor is easier to install, but disturbance variables such as air turbulence have a more profound effect on the measurement result. The air that is to be measured flows around the air flow sensor and the sensor is therefore not resistant to contaminants in the air. Proper mounting of the air flow sensor in the correct position significantly facilitates a reproducible measuring result. The SCHEIDER FM100 and FM500 monitoring systems work perfectly with both measuring systems and safely and reliably monitor fume hoods and extraction systems with variable or constant volume flows. The im50 monitoring system includes an integrated flow sensor and is therefore only suitable for monitoring the constant face velocity. 3

4 Exhaust air Fume hood monitors 4.1 Functional diagram FM100 fume hood monitor The functional diagram in figure 2.3 shows how the SCHNEIDER FM100 fume hood monitor works. Battery backup p Fume hood monitor FM VAC Power Day/Night operation Digital In-/Outputs 4 Fume hood 3 Functional display High Okay Analogue Output 5 Air volume display m 3 h 6 Low Reset RS 232 Supply air Monitoring according to EN Service module SVM Maintenance-free measuring system 2 Static differential pressure transmitter or alternate 3 Air flow sensor 4 Digital In-/Outputs for special application 5 Analogue Output ( VDC) for room group controller 6 Optional air volume (m 3 /h) or air flow (m/s) display F1 F2 F * 0, Laptop Figure 2.3: Functional diagram FM Functional description FM100 With the SVM100 service module or a laptop with the PC2500 software installed, all parameters, such as setpoint volume flows (normal operation, night-time operation, etc.), alarm delay time, alarm threshold, etc., can be programmed. The exhaust air volume flow or optionally the face velocity is continuously measured and compared with the programmed setpoints. When the exhaust air setpoint is underrun, an optical and acoustic alarm is activated. The acoustic alarm can be acknowledged with the Reset button, while the optical alarm is only switched off when the exhaust air setpoint is either reached or exceeded. The Close sash LED flashes when the fume hood sash is opened more than 50 cm (working height exceeded). The emergency power pack guarantees a supply of power in the case of a mains voltage failure. This status is signalled by the LEDs on the function display. Thus all valid standards are fulfilled. 5.1 Interfaces The potential-free relay contacts for malfunction and operating notifications make it possible to easily connect to the building services management (BMS). Analogue actual value outputs of the exhaust air volume flow make it possible to integrate with the supply and exhaust air controller for one or more laboratories. FM100 and FM500 also have a serial or LON interface (optional) for BMS monitoring/control as well as a standardscompliant analogue output V (corresponds to 0m 3 / h m 3 /h). All system data are freely programmable via the SVM100 service module. 4

5 6.1 Schematic diagram FM100 Figure 2.4 shows the schematic diagram of the entire FM100 fume hood controller Power supply All SCHNEIDER products have their own 230V AC power supply, which eliminates the need for a 24V AC power supply via an external transformer. The integrated power supply makes planning easier, generates no additional costs and considerably improves system safety and stability of the electronics. With an external 24 V power supply the entire supply line would fail in the case of a short circuit or other defect. The external emergency power pack is installed when the mains supply does not provide an uninterrupted power supply (UPS). In the case of a mains voltage failure, this is reported and the monitoring function is maintained via the emergency power pack. Output-Ports and an A/D (Analogue/Digital converter). In addition to a CPU kernel, there is also a D/A (Digital/ Analogue converter) as well as an input and an output interface on the control board. The peripheral sensors are connected to the corresponding port cables. The parameters are saved mains voltage failure-free in the EE-PROM Two independent watchdogs circuits The FM100 fume hood monitor has two independent watchdog circuits. The microcontroller is checked for errors at regular intervals and in the case of an error in the CPU, one or both of the watchdog circuits trigger a hardware reset, which restarts the CPU. This extended watchdog concept additionally increases operating safety CPU set-up The CPU consists of a microcontroller with integrated RAM (Random Access Memory), a ROM (Read Only Memory) for the application software, a UART (Universal Asynchronous Receiver Transmitter), internal timers, Input/ Figure 2.4: Schematic diagram FM100 Watchdog 2 EE-PROM Relay Output TTL Relay: Light Operation Alarme TTL: Display Analogue output for room control D/A I/O ROM/RAM Differential pressure transmitter or Air velocity sensor GND +5V +12V CPU A/D Watchdog 1 Timer UART TTL Input TTL: OC: Display Night On/Off Optocoupler RS 232 Voltage supply Main voltage 230/115 V AC Power supply Battery backup Serial interface 5

6 7.1 Terminal diagram FM100 Figure 2.5 shows the terminal diagram of an FM100 fume hood monitor as well as the wiring plan and the hose connection to a static differential pressure transmitter. All cables are pre-assembled and ready to plug in. This ensures that wiring is easy, cost-efficient and error-free. The following points must be completed when carrying out the wiring: 1. Connection of the function display cable to X7 (FAZ1). 2. Connection of the external power pack, if an uninterrupted power supply (UPS) is not available. 3. Connection of the hoses of the differential pressure transmitter (+) = positive pressure (red hose) and (-) = negative pressure (blue hose) Note: If no measuring device is available, only attach the (-) = negative pressure hose 4. Connection of the 230 VAC power supply to terminal X1. 5. Connection of a fluorescent tube (with electronic ballast) for lighting the fume hood interior (optional) to terminal X3 LIGHT FUME HOOD ON/OFF. 6. When the function display is carried out with the LED CLOSE SASH, connect the contact to terminals X9.13 and X9.14 (contact closed = LED flashes, contact open = LED is out). When the parameters have been entered the set-up is complete and the fume hood controller functions automatically. Technical data sheets, further information and tender specifications for the FM100, FM500 and im50 fume hood monitors are available for download on the Internet at 6

7 Figure 2.5: Terminal diagram FM100 Measuring tube - + Fume hood FLOW SENSOR (optional) Monitoring according to EN High Okay Low Reset FUNCTIONAL DISPLAY standard or customer version Servicemodule SVM-100 Supply air F1 F2 F * 0, Laptop - = underpressure Battery backup + = overpressure STATIC DIFFERENTIAL PRESSURE TRANSMITTER Measuring range: Pa X 7 X 6 FAZ 1 FAZ 2 X8 In1 In2 X10 JP2 Exhaust air actual value V DC GND 0...5/10V DC GND ANALOGUE OUTPUT V DC, 10mA ANALOGUE INPUT 0...5/10V DC, 1mA X 5 JP1 Serial In 1 On/Off FAULT K1: max. 3A/250V AC VENTILATOR ON/OFF K2: max. 3A/250V AC LIGHT FUME HOOD ON/OFF K3: max. 12A/250V AC MAKE SURE TO USE THE RIGHT FUSES Operation Fault MOTOR ON L EARTH NO NC COM NO NC COM N X 4 Parallel K1 K2 K3 X3 EARTH X2 X1 - (black) + (red) L N In 2 In 3 X 9 Run TRANSFORMER PRIM: 230 VAC, 50/60Hz SEK I: 9 V~/5 VA Day/Night monitoring LED-Sash position >50cm DIGITAL INPUTS Max. cable length <5m N L N L FUME HOOD MONITOR according to EN Terminal diagram Rev.: 0.2 FM100 Date: 15. December

8.1 Function display and control panel A typical function display is shown in Figure 2.6. SCHNEIDER offers various standard versions (see Technical data sheets, Function displays on the Internet).

6: Function display and control panel LED HIGH This yellow LED shows that the programmed exhaust air volume flow has been exceeded.

8 8.1 Function display and control panel A typical function display is shown in Figure 2.6. SCHNEIDER offers various standard versions (see Technical data sheets, Function displays on the Internet). We also provide customer-specific function displays which harmonise with the design of the fume hood. Figure 2.6: Function display and control panel LED HIGH This yellow LED shows that the programmed exhaust air volume flow has been exceeded. This LED is an indicator that the fume hood is being operated with an exhaust air volume flow that is too high. V max ON/OFF With the Vmax button the exhaust air volume flow is increased to the maximum value. The yellow LED HIGH flashes to indicate that this is switched on. LED OK This green LED lights up in the normal operating state, i.e. the fume hood is operating with sufficient exhaust air volume flow and is therefore within a safe range. RESET button The acoustic alarm (malfunction due to insufficient exhaust air volume flow) can be acknowledged by pressing the Reset button. The optical alarm cannot be acknowledged and is only switched off when sufficient exhaust air volume flow can be regulated and the fume hood is operated in a safe range. LED LOW This red LED lights up to signal a malfunction, i.e. the fume hood is operating with insufficient exhaust air volume flow and is therefore not containment-safe. LED close sash This LED flashes as a warning signal when the sash is open (> 50 cm). When the sash is shut the LED goes out. SERVICE PLUG Via the programming plug all parameters, setpoints and actual values can be programmed and displayed locally. V min with LED With the V min button the exhaust air volume flow is reduced to the minimum value (night-time reduction). The yellow LED shows that this is switched on. Light ON/OFF With this button the light in the fume hood is switched on and off. I/O button with LED ON The I/O button can be deactivated via the software, if the minimum room air exchange done is via the fume hoods. In this case it must not be possible to switch off the controller. Figure 2.7: Fume hoods with function monitoring in accordance with DIN EN Factory picture: Wesemann 8

9 9.1 Measuring devices for volume flow A suitable measurement system is vital for precise and safe monitoring of the volume flow. For safe operation with the static differential pressure transmitter and reproducible and exact measurement results we recommend the SCHNEIDER maintenance-free measuring device or measuring tube. Figure 2.7: Maintenance-free measuring device, Model PPs, socket/socket DN The maintenance-free measuring device M-xxx (xxx stands for the standard diameter) is shown in figure 2.7 and is available in the standard diameters DN160, DN200, DN250 and DN315. The pipe connection is socket/socket or flange/flange. The valid shield factor for the installation size used must be programmed in the FM100 or FM500 monitoring system. L Pressure nipple - Air direction The measuring tube MT-xxx (xxx stands for the length) is shown in Figure 2.8 and is available in lengths from 160 to 800 mm. It is suitable for fitting in pipes or angled air ducts. The appropriate shield factor S, which is dependent on the fitting situation, must be determined. + Both measuring devices are well suited to retrofitting. The measuring accuracy of the maintenance-free measuring device is better than that of the measuring tube. Figure 2.8: Measuring tube, Model PP 10.1 Performance features fume hood monitors The FM100 fume hood monitor is the standard device for volume flow monitoring. The FM500 device has an additional relay output. The im50 fume hood monitor is the standard device for monitoring face velocity and has an integrated flow sensor. 9

10.1.1 Performance features FM100 Microprocessor controlled monitoring system Low cost system Integrated power supply 230V AC All system data are saved mains voltage failure-safe in the EEPROM

10 Performance features FM100 Microprocessor controlled monitoring system Low cost system Integrated power supply 230V AC All system data are saved mains voltage failure-safe in the EEPROM Programming of all system values via service module SVM100 or laptop computer software PC2500 Monitoring of supply air and exhaust air systems Static differential pressure transmitter with longterm stability. Measuring range: pascal or pascal. Optionally with air flow sensor (face velocity) Monitoring of fume hood operation in accordance with EN with acoustic and optical alarms Optional monitoring of exceedance of a programmable volume flow with optical alarm Optical and optionally acoustic alarm for the operating status Sash > 50cm Programming of a second monitoring value (reduced volume flow during night-time operation) Emergency power pack (optional) for mains voltage failure-safe operation Suitable for all fume hood constructions Figure 2.9: FM100 fume hood monitor Peformance features FM500 Microprocessor controlled monitoring system Integrated power supply 230V AC All system data are saved mains voltage failure-safe in the EEPROM Separate terminal board for fast, simple cable connection Pluggable mainboard for easy setup and servicing Programming and retrieval of all system values via the service module SVM100 or software PC2500 Monitoring of supply air and exhaust air systems static differential pressure transmitter with longterm stability. Measuring range: pascal or pascal. Optionally with air flow sensor (face velocity) Monitoring of fume hood operation in accordance with Monitoring of fume hood operation to EN with acoustic and optical alarms Optional monitoring of exceedance of a programmable volume flow with optical alarm Optical and optionally acoustic alarm for the operating status Sash > 50cm Programming of a second monitoring value (reduced volume flow during night-time operation) Emergency power pack (optional) for mains voltage failure-safe operation Integrated battery pack charging connection with low voltage disconnect Suitable for all fume hood constructions Figure 2.10: FM500 fume hood monitor 10

10.1.3 Performance features im50 Microprocessor controlled monitoring system Low cost airflow monitor as a compact fitted version External mains adapter 100.

11 Performance features im50 Microprocessor controlled monitoring system Low cost airflow monitor as a compact fitted version External mains adapter V AC/24V DC All system data are saved mains voltage failure-safe in the EEPROM Integrated password protected operating interface for programming the face velocity alarm values (daytime and night-time operation) and the alarm delay time Programming of all system values via laptop with PC2500 software Monitoring of supply air and exhaust air systems Integrated air flow sensor m/s for measuring the face velocity Monitoring of fume hood operation in accordance with EN with acoustic and optical alarms LED bar graph for displaying the actual value of the face velocity in m/s and ft/min Optical and optionally acoustic alarm for the operating status Sash > 50cm Programming of a second monitoring value (reduced face velocity during night-time operation) Button light ON/OFF (fume hood interior) ON/OFF button for direct actuation of a fan Suitable for all fume hood constructions Figure 2.11: im50 fume hood monitor 11

12 11.1 Product overview fume hood monitors The diagram shows an overview of the products that are available from SCHNEIDER in the product group Fume hood controllers. See Chapter 1, Section 6.1 for the full LabSystem product overview. Technical data sheets, further information and tender specifications for the FM100, FM500 and im50 fume hood controllers are available for download on the Internet at Product group Product Short description Chapter Fume hood monitors in accordance with DIN EN FM100 FM500 Volume flow monitor with static differential pressure transmitter, optionally face velocity control with a flow sensor Volume flow monitor with static differential pressure transmitter, optionally face velocity control with a flow sensor im50 Face velocity monitor with integrated flow sensor Measuring device for volume flow M-xxx Maintenance-free, self-cleaning measuring device with annuli that form the mean value for volume flow measurement. MT-xxx Measuring tube, suitable for retrofitting in pipes and rectangular ducts

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