Omega DPF75, DPF78, DPF76 manual Calculating Scale Factors, Scaling Factor Examples

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CALCULATING SCALE FACTORS

There are two separate dividing scale factors, one for input "A" and one for input "B". The factor to enter is the number of pulses per the desired unit of measurement. The factor ranges from 0.0001 to 99999. The factor is the same for rate and count on input "A". Because the "units per second", "minute", or "hour" are field programmable from the keypad, scale factor calculations for the ratemeter are easy. Here are some examples:

SCALING FACTOR EXAMPLES:

BATCHING: You want to count the number of batches (10 boxes each) being loaded onto a pallet. Solution - Dial in a scale factor of 10.

UNIT COUNTING: You pick up a notch on a paper roll (1 pulse per shaft revolution). Each revolution equals 3 feet. To find the number of pulses per foot, simply divide "1 pulse" by "3 feet" (13 = .3333).

Solution - One foot equals 0.3333 pulses, enter this as the scale factor and the display will read in feet.

RATE: The shaft of a motor has a flywheel with 10 spokes. A prox switch is mounted to sense 10 pulses per revolution. RPM of the shaft is the desired readout.

Solution: Enter a Factor of 10 and for every 10 pulses, "1" will appear on the display. Set rate per second, minute or hour as desired.

A conveyor carrying bottles must be controlled for bottle speed. For each revolution of the front roller, three bottles travel by. Thus, one revolution equals 3 bottles. A wheel with seven spokes is mounted on the roller. The user can't sense bottles because they are traveling through a washer, so a sensor is placed at the roller, sensing seven pulses per revolution of the shaft, which equals 3 bottles per revolution.

To calculate the scale factor (7 ppr 3 bottles) = 2.3333 scale divider. Set rate per second, minute or hour as desired.

A flow meter is generating 52.6 pulses per gallon. The desired readout is in liters. Since there are 3.785 liters per gallon, divide 52.6 by 3.785 to find the number of pulses per liter (52.6 3.785 = 13.897).

Enter 13.789 as the scale factor so the display will read in liters.

An aluminum sheeting plant has a cut to length application to customer specification. A ten pulse per revolution encoder with a 12" wheel is used to sense. The travel of aluminum sheets is in inches. Thus, after 10 pulses, you want 12 to appear on the display. Thus, 10 12 = .8333. Enter .8333 as your scale factor.

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Contents User’s Guide For immediate technical or application assistance Table of Contents Quick SET-UP Guide Programming ExampleCounter DPF75, DPF76 Description & Specifications DescriptionHOW to Mount the Unit DimensionsQuadrature Input WiringUP/DOWN Control and Quadrature Inputs UP/DOWN ControlConnecting AC / DC Power Wiring Considerations Do not USE PIN 7 with These Meters=CLOSE, O=OPEN What can YOU VIEW?Output Jumper Selections Millivolt Input Option 30V InputProgram Programming FlowchartOperating the Front Panel Program Codes and Descriptions Portion of Menu for Setting Counter VariablesPortion of Menu for Setting Rate Variables DescriptionTerminations Rear ViewCalculating Scale Factors Scaling Factor ExamplesRemarks ProgrammingPress ScalingSetting Counter PrgmSetting Rate Remarks DisplayLock SettingLock Remarks Press Setting RelaysPresets Analog Output Output WiringAlarms Analog Output Option DescriptionInterface Card RS 232/422 Operation Placed in ANY of These Data Values Serial Input CommandsUnit will Recognize a Decimal if ONE is †THE Unit will only Recognize the Last FivePrinter Hookup DP -9 Connector ComputerComputer Hookup Troubleshooting Guide Problem Possible Causes SolutionsPage Page Page WARRANTY/DISCLAIMER Temperature