Pellistor Catalytic Gas Detector

VQ1Combustible Gas Detector Elements2 V1 kOZERO SET27O27OOUTPUTCOMPENSATOR(BLACK SLEEVE)DETECTOR(RED SLEEVE)2309CRSEENOTE 5To be read in conjunction with "Introduction to Pellistor GasSensors" and Pellistor Application Notes 1, 2, 3, 4, 6 and 7.INTRODUCTIONThe VQ1 consists of two matched elements which are used forthe detection of combustible gases, particularly methane in airmixtures in concentrations from 0.1% upwards. There is nointerference from water vapour or carbon dioxide. Using therecommended bridge circuit (see below) and the mountingarrangement shown on page 2, the minimum sensitivity is20 mV/% methane.GENERAL DATAElectricalThe information given below relates to the VQ1 operating in therecommended circuit shown.Operation (see note 1) . . . . . . . . . continuousBridge supply . . . . . . . . . . . 2.0+ 0.1 VBridge power consumption . . . . . . . 0.75 W maxMinimum sensitivity (see note 2) . . . 20 mV/% methaneLinearity . . . . . . . . . linear up to 3% methaneResponse time to register 1 1/4% in a 21/2%concentration (see notes 2 and 3) . . . . 2 secondsMaximum methane concentration(see note 4) . . . . . . . . . . 10 %MechanicalMounting . . . . . . . . . . . . . . see page 2Outline . . . . . . . . . . . . . . . see page 2Shock test . . . . . . . 250 g, 5 blows in each planeVibration test . . . . 20 g, 24 cycles from 100 to 3200 HzBRIDGE CIRCUITMARKINGEach element carries a serial number sleeve, fitted to one of theflexible leads. The number is in standard colour code (seetable), reading from the base towards the free end of the lead.Colour CodeBlack 0 Yellow 4 Grey 8Brown 1 Green 5 White 9Red 2 Blue 6Orange 3 Violet 7The detector bead is dark in colour and has a red sleeve on thesecond lead. This sleeve carries a letter code which, togetherwith the serial number, fully identifies a pair of elements.The compensator bead is white and carries a black sleeve onthe second lead.NOTES1. Operation may be under either direct flow or diffusionconditions in appropriate mountings (see page 2).2. With open-circuit conditions at the bridge output.3. The response time is a function of the type of mountingused.4. If the VQ1 is exposed to greater than 5% methaneconcentration, the calibration of the instrument should bechecked.5. The elements are supplied as a matched pair with atrimming resistor R of the correct value which is between39 and 120 O. The trimming resistor is to be connectedacross the compensator element as shown below.6. The elements must be protected from certain organic andsilicone vapours by suitable filtering, and caution should beexercised when operating in close proximity to hot, oilymachinery.# e2v technologies (uk) limited 2007 A1A-VQ1 Issue 4, March 2007101182e2v technologies (uk) limited, Waterhouse Lane, Chelmsford, Essex CM1 2QU, UK Telephone: +44 (0)1245 493493 Facsimile: +44 (0)1245 492492e-mail: enquiries@e2v.com Internet: www.e2v.com Holding Company: e2v technologies plce2v technologies inc. 4 Westchester Plaza, PO Box 1482, Elmsford, NY10523-1482 USA Telephone: (914) 592-6050 Facsimile: (914) 592-5148e-mail: enquiries@e2vtechnologies.us1AD F1GHEC1BINSULATOR METALFLANGESEE NOTEJ O-RING2311BOUTLINE(All dimensions without limits are nominal)Note No bends may be made in this length.Ref Inches MillimetresA 0.435+ 0.010 11.05+ 0.25B 0.240+ 0.010 6.10 + 0.25C 0.140+ 0.005 3.56 + 0.13D 2.500 min 63.5 minE 0.040 1.02F 0.230+ 0.020 5.84 + 0.51G 0.323 max 8.20 maxH 0.375 9.53J 0.060 1.52Millimetre dimensions have been derived from inches.Ref Inches MillimetresAA 0.750 max 19.05 maxAB 0.375+ 0.005 9.53 + 0.13AC 0.328+ 0.005 8.33 + 0.13AD 0.323 min 8.20 minAE 0.750 max 19.05 maxAF 0.375+ 0.005 9.53 + 0.13AG 0.323 min 8.20 minMillimetre dimensions have been derived from inches.Printed in EnglandVQ1, page 2 # e2v technologiesWhilst e2v technologies has taken care to ensure the accuracy of the information contained herein it accepts no responsibility for the consequences of any usethereof and also reserves the right to change the specification of goods without notice. e2v technologies accepts no liability beyond that set out in its standardconditions of sale in respect of infringement of third party patents arising from the use of tubes or other devices in accordance with information contained herein.AAABAC1AD60 MESH STAINLESSSTEEL GAUZEFLOW RATE 500 cm3/minLEAKPROOFJOINTAEFILTER PAPER AND60 MESH STAINLESSSTEEL GAUZE1AGAF2310CRECOMMENDED MOUNTING ARRANGEMENTS