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Our steel constructed,two-component polyurethane painted Air Flow Calibrator (AFC) housings incorporate a precision machined venturi tube to create a pressure differential across a fixed orifice.By varying the air flow velocities,the pressure differentials are measured &recorded against a laminar flow element whose calibration is certified and traceable to the National Institute of Standards and Technology (N.I.S.T.).The AFC ’s overall internal simplicity of operation reduces the frequency of recalibration to once or twice per year depending on (individual)regulatory protocol.AFC-XX series air flow calibrators are intended to be used open to air.
Dual Range AFC
By varying the orifice size and the chosen Magnehelic ® ((Standard AFC) or differential pressure sensor/transmitter (AFC-DIGITAL), We can fabricate calibrators in almost any desired flow range.Unlike other manufacturers,we do not use pre-silk screened dial faces in their analog AFC units. GENEQ individually hand marks each AFC dial face. Flow vs.Pressure Differential produces a logarithmic reading on a Magnehelic ® gage. The spacing between the numbers on the lower end of the scale will be close together and further apart on the upper end of the scale. For the greatest visual accuracy, GENEQ suggests, ordering a unit with the lowest upper range as practical (i.e.:don ’t select an AFC-8 if your pump only draws a maximum of 4 CFM).
Analog style AFC
Analog style AFC units house a Magnehelic ® differential pressure gage, whose relative volumetric flow rate units are transferred onto a direct reading scale.A reflective tape on the scale,behind the analog needle,reduces parallax error. Overall accuracy on analog AFC units is better than ±5%.
Digital style AFC
Digital style AFC units house an LED display which employs advanced technology for stable,drift free,readout while incorporating features that provide flexibility now and in the future with Plug-in option cards available for alarm contacts,analog output,and serial communication.The AFC-DIGITAL ’s Rate/Total dis- play indicates air flow rate in Actual Cubic Feet per Minute (ACFM) and displays total volume sampled in Actual Cubic Feet (ACF).Metric calibration is also available.Accuracy:+/-1%full scale at calibration points.(15 points per standardcalibration).Contact GENEQ for Analog to Digital Conversion kits.
Dual Range ACF
If you require visual accuracy over a large flow range,or wish to calibrate a number of air flow units consisting of more than one flow range,select GENEQ’s Dual Range AFC.The Dual Range unit consists of two pressure differential gauges installed in a single cabinet,that precisely measures both the low and high rate of air through a single venturi.
The HFC-Series,HI-Volume Air Flow Calibrators,have eliminated the need for cumbersome orifice plates and water manometers.The HFC-XXC series units utilize a precision machined Venturi tube coupled with a pressure differential gauge giving a direct reading in the volumetric units of your choice (i.e.SCFM @stp).The unit is calibrated against an in-line N.I.S.T.traceable laminar flow element.The primary calibrator meets the requirements of MIL Std.45662A.HFC-XX series units are intended to be used open to air.
The direct meter read-out will indicate the flow in standard CFM,LPM,or CMM at standard conditions (29.92"of Hg and 70 º F)). Given actual sampling tempera- ture &barometric pressure during calibration,a technician can convert actual flow readings (i.e.ACFM)to standard units (i.e.SCFM) by making a simple calculation using look-up correction factors from tables given in the operating manual.
Depending on orientation at calibration (vertical vs.horizontal), GENEQ offers two HFC models:The HFC-XX is intended for high flow calibrations in the verticalplane,such as seen with the “HVP ” style high volume air samplers..Whereas HFC-SIDE-XX is intended for the calibration of low to high flow rates in the horizontal plane,such as seen with the line of portable continuous duty and grab air samplers.
The HFC-XX series units have a standard 1 1ž2"male straight pipe thread (MSPT) which can be screw into most low to medium volume air sampling pumps (ie:CF-1001 or CF-901 ).On higher volumetric flow samplers,a user must incorporate an adapter plate.With the use of FHA-4CF 4"diameter adapter disc,an operator is able to calibrate a unit with a 4"diameter filter holder assembly. The FHA- 810CF adapter plate is used to calibrate units with an 8"x 10"paper holder.
Replace “XX ” with the uppermost desired flow rate..If a dual scale reading is required (i.e.both CFM &LPM displayed on one scale) replace “C ” with “DSC ” (e.g.order:HFC-50DSC for 10-50 CFM &280-1500 LPM marked scale) High Volume,Single Range Air Flow Calibrators ranges be- tween 10-50 CFM (280-1500 LPM)
The V-FLO-XX series units incorporate a flowmeter and a precision- machined venturi tube to create a pressure differential across a fixed orifice which floats the indicating ball in the flowmeter.By varying the flow velocities,the pressure differentials are measured &recorded against a laminar flow element whose calibration is certified and traceable to the National Institute of Standards and Technology (N.I.S.T.). The recorded volumetric flow units are then marked directly on the attached flowmeter scale. V-FLO models are accurate within ±5%of full scale reading. The standard V-FLO-XX body is six inches long and threaded on bothends with 3/8"female NPT. The complete unit includes one male (outlet)&one female (inlet)3/8"quick disconnect fitting.The V-FLO XX,venturi flow meters are intended for in-line use. Ordering Information for Venturi Flow meters:On custom units replace “XX ” with the uppermost desired flow rate. If a dual scale reading is required (i.e.both CFM &LPMdisplayed on one scale)add the letters “DSC ” to the end of the model number ((e.g.order:V-FLO-5-DSC for 1-5 CFM &28-140 LPM marked scale). Note:Larger Flow meters with expanded scales are available.
Air Flow Calibrators are generally used to verify the displayed sample flow rate accuracy of complete air sampling systems.Along with the flow measuring device to be calibrated,it is recommended that a “Complete” system for calibration should also includes the actual filter holder and filter media in order to duplicate realistic pressure drops experienced in a true sampling environment.The following adapters allow a technician to connect an Air Flow Calibrator at the end of (open to air) an “In-Line” High, Medium or Low Volume Air Sampling calibration set up.
Standard Calibration set-up,from right to left,(as shown in picture)is as follows: