FLAME SENSOR UVTRON ® R2868 Quick Detection of Flame from Distance, Compact UV Sensor with High Sensitivity and Wide Directivity, Suitable for Flame Detectors and Fire Alarms. Hamamatsu R2868 is a UVTRON ultraviolet ON/OFF detector that makes use of the photoelectric effect of metal and the gas multiplication effect. It has a narrow spectral sensitivity of 185 nm to 260 nm, being completely insensitive to visible light. Unlike semiconductor detectors, it dose not require optical visible-cut filters, thus making it easy to use. In spite of its small size, the R2868 has wide angular sensitivity (directivity) and can reliably and quickly detect weak ultraviolet radiations emitted from flame due to use of the metal plate cathode (eg. it can detect the flame of a cigarette lighter at a distance of more than 5 m.). The R2868 is well suited for use in flame detectors and fire alarms, and also in detection of invisible discharge phenomena such as corona discharge of high-voltage transmission lines. APPLICATIONS ●Flame detectors for gas / oil lighters and matches ●Fire alarms ●Combustion monitors for burners ●Inspection of ultraviolet leakage ●Detection of discharge ●Ultraviolet switching SPECIFICATIONS GENERAL Parameter Spectral Response Window Material Weight Description / Value 185 to 260 UV glass Approx. 1.5 Unit nm — g Value 400 30 1 -20 to +60 Unit V mA mA °C RELATIVE SENSITIVITY, RELATIVE INTENSITY (ARBITRARY UNIT) Figure: UVTRON's Spectral Response and Various Light Sources 100 TPT B0009EB UVTRON's SPECTRAL RESPONSE SUNLIGHT 50 GAS FLAME 0 100 200 300 400 TUNGSTEN LIGHT 500 600 700 800 900 WAVELENGTH (nm) ULTRAVIOLET VISIBLE INFRARED MAXIMUM RATINGS Parameter Supply Voltage Peak Current 1 Average Discharge Current 2 Operating Temperature CHARACTERISTICS (at 25 °C) Parameter Discharge Starting Voltage Max. (with UV radiation) (DC) Recommended Operating Voltage (DC) Background 3 Max. Sensitivity 4 Typ. Value Unit 280 V 325 ± 25 10 5000 V min-1 min-1 NOTE: 1This is the maximum momentary current that can be handled if its full width at half maximum is less than 10 µs. 2If the tube is operated near this or higher, the service life is noticeably reduced. Use the tube within the recommended current values. 3Measured under room illuminations (approx. 500 lux) and recommended operating conditions. Note that these values may increase if the following environmental factors are present. (1)Mercury lamps, sterization lamps, or halogen lamps are located nearby. (2)Direct or reflected sunlight is incident on the tube. (3)Electrical sparks such as welding sparks are present. (4)Radiation sources are present. (5)High electric field (including static field) generates across the tube. 4These are representative values for a wavelength of 200 nm and a light input of 10 pW/cm2. In actual use, the sensitivity will vary with the wavelength of the ultraviolet radiation and the drive circuitry employed. Subject to local technical requirements and regulations, availability of products included in this promotional material may vary. Please consult with our sales office. Information furnished by HAMAMATSU is believed to be reliable. However, no responsibility is assumed for possible inaccuracies or omissions. Specifications are subject to change without notice. No patent rights are granted to any of the circuits described herein. ©2008 Hamamatsu Photonics K.K. FLAME SENSOR UVTRON ® R2868 Figure 2: Angular Sensitivity (Directivity) VERTICAL VIEWING (Left fig.) 0° 100 % 0° 100 % 30° 30° 30° 80 60 60° 60° 40 60° 40 20 20 90° 90° ANODE CATHODE 90° 90° ANODE CATHODE UV GLASS BULB A ANODE LEAD A' 10 MΩ + 4.7 kΩ* ANODE CATHODE LEAD UVTRON R2868 8±1 ANODE ANODE TPT B0010EA Figure 4: Recommended Operating Circuit 9.0 ± 0.5 CATHODE 5 × 12 12 MAX. Figure 3: Dimensional Outline (Unit: mm) CATHODE HORIZONTAL VIEWING (Left fig.) 80 60 60° UV EMISSION POINT 23 ± 1 DC 325 V ± 25 V 8 ± 1 4±1 PULSE OUTPUT i 32 MIN. TOP VIEW A – A' CATHODE 220 pF 500 V 44 MAX. 10 kΩ 1000 pF – SIDE VIEW * Be sure to connect the 4.7 kΩ resistor within 2.5 cm from the anode lead end of UVTRON. ANODE TPT C0003EB LEAD: 0.65 ± 0.05 CATHODE ●UVTRON Driving circuit C3704 series (sold separately) 18 MAX. TPT A0023EB Hamamatsu also provide the driving circuit C3704 series for R2868 operation. C3704 series include a high voltage power supply and a signal processing circuit in printed circuit board, which allows to operate R2868 easily as a flame sensor with the low input voltage (DC 5 V to 30 V) only. For the details, please refer to the data sheet of C3704 series. ■PRECAUTIONS FOR USE ●Ultraviolet Radiation The UVTRON itself emits ultraviolet radiation in operation. When using two or more UVTRONs at the same time in close position, care should be taken so that they do not optically interfere with each other. ●Vibration and shock UVTRONs have passed vibration and shock tests in compliance with IEC 60068-2-6 (sinusoidal vibration test 1.5 mm peak to peak, 100 m/s2, 10 Hz to 500 Hz) and IEC 60068-2-27 (shock test 1000 m/s2, 11 ms). However if subjected to strong mechanical shocks such as drop impacts, the glass envelope may crack or internal electrodes may deform resulting in poor electrical characteristics. So use extreme caution when handling the UVTRON. If the leads are machined or cut with a wire cutter, the internal electrodes may be subjected to vibrations or shocks greater than the above tests, resulting in poor electrical characteristics as in the case where they are subjected to drop impacts. ●Polarity Connect the UVTRON with correct polarity. Should it be connected with reverse polarity, operating errors may occur. ■WARRANTY The UVTRON is covered by a warranty for a period of one year after delivery. The warranty is limited to replacement of any defective tube due to defects traceable to the manufacturer. WEB SITE www.hamamatsu.com HAMAMATSU PHOTONICS K.K., Electron Tube Division 314-5, Shimokanzo, Iwata City, Shizuoka Pref., 438-0193, Japan, Telephone: (81)539/62-5248, Fax: (81)539/62-2205 U.S.A.: Hamamatsu Corporation: 360 Foothill Road, P. O. Box 6910, Bridgewater. N.J. 08807-0910, U.S.A., Telephone: (1)908-231-0960, Fax: (1)908-231-1218 E-mail: [email protected] Germany: Hamamatsu Photonics Deutschland GmbH: Arzbergerstr. 10, D-82211 Herrsching am Ammersee, Germany, Telephone: (49)8152-375-0, Fax: (49)8152-2658 E-mail: [email protected] France: Hamamatsu Photonics France S.A.R.L.: 19, Rue du Saule Trapu, Parc du Moulin de Massy, 91882 Massy Cedex, France, Telephone: (33)1 69 53 71 00, Fax: (33)1 69 53 71 10 E-mail: [email protected] United Kingdom: Hamamatsu Photonics UK Limited: 2 Howard Court, 10 Tewin Road Welwyn Garden City Hertfordshire AL7 1BW, United Kingdom, Telephone: 44-(0)1707-294888, Fax: 44(0)1707-325777 E-mail: [email protected] North Europe: Hamamatsu Photonics Norden AB: Smidesvägen 12, SE-171-41 SOLNA, Sweden, Telephone: (46)8-509-031-00, Fax: (46)8-509-031-01 E-mail: [email protected] TPT 1008E02 Italy: Hamamatsu Photonics Italia: S.R.L.: Strada della Moia, 1/E, 20020 Arese, (Milano), Italy, Telephone: (39)02-935 81 733, Fax: (39)02-935 81 741 E-mail: [email protected] DEC. 2008 IP