BX444 Gas Detector BX444 Four Zone Gas Detector Duomo is recognised within the Gas industry for providing a comprehensive range of low cost, high reliability gas detection for many applications. We have installed and commissioned Natural gas and carbon monoxide sensors in applications such as boiler rooms, kitchens, car parks, aircraft hangars, factories and shopping centres. Application The BX444 has been designed to meet all European Normative proposals for the detection of Natural Gas, LPG and Carbon Monoxide Gas Detectors. The BX444 is provides protection from gas leakage in areas such as Boiler Rooms Roof spaces unventilated voids. Carbon Monoxide is an invisible, odourless gas which inhibits the bodies ability to process Oxygen. The BX444 protects against this in underground or poorly ventilated car parks, boiler rooms, vehicle servicing areas etc. Remote sensors are installed in the areas which require connected to remote sensors located in the protected area. The 144 x 144 enclosure is wall or panel mounting. Operation If the remote sensors sense the presence of Gas the detector operates a pre-alarm relay - used for remote sirens or extract fans; if the level of gas continues to rise then the main alarm relay is activated to, either in the case of explosive gases, break the electrical supply to the Safety Shut Off Valve or for CO sound a General Alarm to allow evacuation of the area. Detects Carbon Monoxide,Natural Gas & L.P.G. 230V and 12V DC. One, two, three or four Zone. Self Diagnostic Manual or Automatic Reset Adjustable Pre-Alarm Catalytic and Electrochemical Sensors Audible Alarm Sensor Fault Alarm Manual Test Function 144 x 144 DIN Enclosure Panel or wall Mounting 1 Year Guarantee Features The Pre-Alarm can be adjusted, in the case of Natural Gas or LPG, from 8% to 15% of the Lower Explosive Level (LEL). For Carbon Monoxide, it can be adjusted from 120ppm to 250ppm. The Main Alarm thresholds are not adjustable and are fixed at 20% LEL for explosive gas and 300 ppm for Carbon Monoxide. The detectors can be set for either toxic or explosive Gas. Or both. It is possible to set one zone for explosive gas such as Natural Gas or LPG and another for toxic gas for example Carbon Monoxide. An LED display on the fascia indicates the levels of detected gas in either:- parts per million (ppm) or percentage of Lower Explosive Level (%LEL). Lights above the display indicate which sensor the Numeric LED display refers to. It is possible to use the detector as a one, two, three or four zone by enabling or disabling each channel. A TEST button on the facia, when pressed, checks the complete function of the BX444 and sensors. A permanent diagnostic check is made of sensor function. If any sensors should become faulty or be connected incorrectly the FAULT light will illuminate and the detector will fail safe. CAUTION! Carefully read the following instructions prior to installation of this device. Always keep this pamphlet for future reference. Ensure that the gas detection system is wired correctly, the appropriate sensor is installed and used only for the purpose which it is intended.
BX444 Facia 1 2 3 4 5 14 13 12 6 7 8 11 10 9 Key 1 EXPLOSIVE - Indicates when the natural gas & LPG function is selected. 2 SENSOR LED s - These show which sensor the displayed levels refer to. 3 Numeric LED display - This shows the concentration of detected gas in either ppm or as %LEL. 4 LEL - This shows that the numeric display refers to % LEL. 5 ON - indicates external power source is healthy. 6 BATTERY - 12V battery connected rather than mains supply. 7 PRE-ALARM - Indicates when the gas level has reached the selected pre-alarm threshold. 8 MAIN ALARM- Indicates when the concentration of gas reaches 20% LEL Methane or 300ppm of Carbon Monoxide. 9 PPM - The LED numeric display refers to parts per million of the detected gas. 10 RESET - Press to reset alarm. This resets the detector memory. 11 TEST- Push button. Provides full function test of detector. 12 FAULT - Flashes when the sensor is either faulty, connected incorrectly or not selected. 13 OVERLOAD - Power consumption of the BX444 is too high. 14 TOXIC - Indicates that the Carbon Monoxide function is selected. Digital Display This shows the quantity of gas detected by each sensor. The display can be configured to display values in parts per million (ppm) percentage of the lower explosive level (LEL). As the blue lights marked 1 to 4 illuminate, the value shown on the display corresponds to the gas levels detected by sensors 1 to 4 respectively. During the Reset procedure the explosive, toxic, sensor 1,2,3 and 4 lights will flash. The display will scroll through numbers up to 990 for each zone and then will stabilize at 000.
Installation Mounting the detector Fig.1 The BX444 can be wall mounted or panel mounted. See fig.(2) for panel cutout dimensions. When panel mounted the support bracket supplied loose should be fitted as shown in fig.(3) Cable gland entries are provided in the form of 2 pre-moulded 20mm knockouts in the back of the BX444 box. Alternatively it is possible to carefully drill into the sides of the box. Note: See fig.(4) for suitable drill positions. Always ensure that the printed circuit board will clear the cable gland when closed. It is recommended that the PCB facia assembly is removed prior to drilling for gland entry. Fig.2 Positioning Sensors The SG590 (Methane) and CO100 (Carbon Monoxide) Sensors should be mounted in accordance with the following considerations. Do not position next to burners, heaters or ovens where temperatures above the room ambient may be experienced. It is, if possible, better to mount the sensors on the opposite wall. This is, of course, dependant on the size of the protected area. Fig.3 Natural Gas is lighter than air and therefore will obviously rise, therefore the SG590 (methane) sensor should be mounted 300mm from the ceiling of the protected area. For LPG (Propane and butane) the SG590 LPG must be connected. LPG is heavier than air so the sensor must be located 300mm from floor level. Carbon Monoxide has specific gravity of 0.97 and is therefore slightly lighter than air. However for positioning purposes at the concentrations of CO relating to the detector alarm thresholds the resultant combination of CO and air will neither rise or fall. The best position to mount the C0100 is 1.6m above ground level. If you require assistance regarding locating sensors please call our Droitwich Factory on (01905) 797989 alternatively fax a drawing of your application to (01905) 774296 and we will advise accordingly.
Typical External Wiring Diagram for BX444 Electrical Connection The sensor can be located up to 100m from the gas detector. Cable size should be 1mm CSA. If the sensor cables are run separately in specific conduit it is not essential to use screened cable but if the cables are routed through conduit or trunking containing other wiring the use of screened cable is advisable. The wiring should be performed by a qualified person in accordance with current regulations. The plug in terminal rail makes installation easy and quick. Note: It is essential that enough length is left in the cable loom to allow the facia to be hinged open as shown in fig (3). The wiring must be checked prior to powering up the system. Cable Entry Points Fig.4
Printed Circuit board Layout Explosive or Toxic selectors Zone selectors ppm/lel & auto/ manual reset selectors Pre-alarm adjustment Terminal block 1 Continuous/pulsed main alarm jumper Terminal block 2 Configuring the detector How Many zones...? The BX444 can be configured to provide one, two, three or four zone protection. Sensors are enabled and disabled by switching the zone select switches on and off. To disable a zone move the switch to the ON position. The switches shown are in the zone enabled position. When you have made the switch change press the reset on the BX444 fascia. Gas or Carbon Monoxide...? If the gas to be sensed is Explosive you must first ensure that the correct sensor is connected to the system. For instance, for Natural Gas SG590. Each pair of switches shown below corresponds to a sensor. From left to right, 1 to 4. To select the Explosive Indication on the fascia for a particular sensor move switch 1 to the ON position and switch 2 to the off position. If another zone is being used to sense carbon monoxide, again ensure that the correct sensor is connected to that zone for example CO200. Select Toxic indication by moving switch 2 to the ON position and switch 1 to the off position. In the above picture this shows zone 1 Toxic, zone 2 explosive, zone 3 toxic, zone 4 explosive. Pre-Alarm Sensitivity Adjustment The Pre-Alarm can be adjusted, in the case of Natural Gas or LPG, from 8% to 15% of the Lower Explosive Level (LEL). For Carbon Monoxide, it can be adjusted from 120ppm to 250ppm. Adjustment is made using the pre-alarm potentiometer marked PT1. To increase the sensitivity turn the potentiometer away from the central point either left or right. i.e. Central Position is 15% LEL. Left or right 8% LEL. Setting Main Alarm Memory function The Main Alarm thresholds are not adjustable and are fixed at 20% LEL for Natural Gas or LPG and 300 ppm for Carbon Monoxide. The main alarm can be configured to provide either a latching or an auto reset relay actuation. For example to turn off gas valves or to boost ventilation in car parks or areas containing carbon monoxide. Should gas be sensed in boiler rooms laboratories etc. the gas valve supplying the room will be turned off by the detector. This must only be manually reset following an alarm. However if the BX444 is being used to control the levels of carbon monoxide in car parks as long as the ventilation is boosted and the levels of Carbon Monoxide drop there is no requirement to maintain the alarm so the unit can be allowed to automatically reset.
Setting Main Alarm Memory function To make the main alarm a latching operation, move switch 1 shown to the off position. (This is the factory setting). For an auto-reset function move switch 1 to the ON position. It is then necessary for the BX444 to be reset in order for this change to take effect. Note: This setting should only be made by a qualified technician. The BX444 can also be set to give a pulsed or continuous main alarm function. This is mainly used to extend battery back up time. For example, if a manual reset solenoid valve is used to shut off the gas the 12V supply does not need to be continuously applied. The valve will only require a trigger pulse to close it. This setting is made by moving the jumper shown below to the I position. The factory setting is continuous. It is again necessary to press the reset to implement this change. Warning The installation of this gas detector does not release the user from observing all the regulations concerning the characteristics, installation and the use of gas appliances; the ventilation of the environment and the elimination of combustion products in accordance with local recommendations, regulations and byelaws. For any damage caused to people, property or animals resulting from incorrect connection, installation or application of this gas detector Duomo will not be held responsible or liable. This Gas detector is a safety device and therefore should only be maintained and installed by qualified persons. To ensure correct function after installation Duomo provide a commissioning service using calibrated test gases. For the service call 01905 797989. IN CASE OF AN ALARM 1 PUT OUT ANY NAKED FLAMES 2 CLOSE THE MANUAL GAS VALVE SUPPLYING THE PROTECTED AREA 3 DO NOT TURN ANY ELECTRICAL DEVICES ON OR OFF. 4 OPEN ALL WINDOWS AND DOORS TO INCREASE VENTILATION 5 IF THE ALARM STOPS IT IS NECESSARY TO FIND THE CAUSE OF THE ALARM BEFORE ATTEMPTING TO RESET THE DETECTOR. THIS MUST BE CARRIED OUT BY A RESPONSIBLE, QUALIFIED PERSON. 6 IF THE ALARM CONTINUES AND THE CAUSE IS NOT EVIDENT OR POSSIBLE TO ELIMINATE, LEAVE THE ROOM AND CONTACT YOUR GAS PROVIDERS EMERGENCY LINE. THEY WILL ADVISE ACCORDINGLY.
Faults - symptoms and solutions When power is applied to the unit no lights or displays are lit. Check the power supply. Check that the terminal plug on the reverse of the pcb is wired properly. Check that the terminal plug is pushed securely into the socket. Fault light is illuminated and the BX444 is in alarm. Has the correct number of sensors been selected on the p.c.b. See configuring the operation of the BX444. Is the green Light illuminated on the sensor? Check sensor connections. Is the connector plug in the sensor secure? Check that there is no interruption to the cable supply to the sensor. The alarm function isn t latching. When gas levels indicated drop below the main alarm threshold the main relay resets. Check the position of the alarm function Switch. There are two modes. i) Auto reset ii) Latch with manual Reset. When you have selected the correct memory function you must press the reset button so that this change takes effect. The main alarm relay changes over the volt-free relay and then with the Main Alarm light still on the relay reenergises. Check the position of the Jumper link JP1. This is located between the two terminal plugs. When in the C position the relay will stay on, either until the level of detected gas drops if set for auto reset or until the level of gas drops and the BX444 is manually reset. If the jumper is set to I position the relay will de-energise momentarily then automatically return to the on position. This function is used when the detector is connected to a manual reset valve which only needs a trigger pulse to close it. This also extends battery backup time as solenoid valves do not need to be constantly powered. Check local regulations recommendations regarding manual reset gas valves and their control.
Gas Detection Product Overview GS100 Single Zone Gas Detector. 230V AC or 12 VDC Supply. GS300 Three Zone Gas Detector. 230V AC or 12 VDC Supply. GS150K Single Zone Gas Detector. 230V AC or 12 VDC Supply. SG590 Catalytic Nat Gas or LPG Gas Sensor. IP55. 12 VDC Supply. 4-20mA output. CO100 Catalytic Carbon Monoxide Gas Sensor. IP55. 12 VDC Supply. 4-20mA output. CO200A CO Sensor for Car Parks. 12 or 24VDC supply 4-20mA Output. IP55 SG580 EX Certified Gas Sensor for Natural Gas and LPG. SG500 Single Zone Gas Sensor. IP30 CO200 and 230 Catalytic Carbon Monoxide Gas Sensor with digital display and Change over Relay. 30ppm CO. IP55. Gas Solenoid Valves from 1/2 BSP to 4 Flanged EN161 approved. Gas Safestart for Kitchens and Laboratories Fact: Manual gas valves do get left on and will be operated by unauthorised individuals. The Duomo Gas Safestart is... a weep bypass assembly which proves that there are no gas taps open or serious leakages in gas pipe-work which relies on manually operated gas valves as the only means of isolation. 2 BSP G621 with lockable bypass KS21 Keystart Control Panel Guarantee This device is guaranteed for a period of 12 months from the date of purchase. Conditions. Substitution free of charge of any component recognized as being faulty from production. The unit must be delivered to the resaler or directly to Duomo. Unit 5 Judge Court, North Bank, Berryhill Industrial Est. Droitwich, Worcestershire, England, UK, WR9-9AU Telephone: 01905 797989 Fax: 01905 774296 email:sales@duomo.co.uk