Omega DPF75, DPF78, DPF76 manual Wiring, UP/DOWN Control and Quadrature Inputs

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WIRING

The rear terminal contains 12 screw terminals for connecting #14 to #28 gauge wire.

The unit is controlled by a microprocessor and, therefore, an electrically "noisy" environment could cause operating problems. The input power line should not be common to power lines for motors, pumps, contactors, etc.

The unit is designed to be immune from line or RF voltage interference. In some environments voltage spikes of over 100 volts, even 1000 volts, can occur. When common to a power line driving motors voltage fluctuations can be extreme and rapid. Lines driving DC or AC solenoids, relays, or actuators can also cause problems.

Four sources of noise can occur:

1)AC power line noise - If the unit cannot be connected to a clean power source, an inductive load suppressing device (MOV as GE # V130LA1 or Resistor Capacitor as Paktron # .2 uf/220 ohm @ 400V) can be installed. Although locating the suppressor across the AC supply at the unit should help, best results are obtained by connecting the suppressor across the leads of the "load" at the device causing the spike.

2)Input line noise -The noise is carried on the input and D.C. ground lines. Make sure the input wires are never run into the unit in a bundle with power input lines. Also, keep these input lines isolated from inductive lines from devices drawing heavy loads. If there is a possibility of electrical noise, we recommend using shielded cable, with the shield being hooked to the D.C. ground terminal on the instrument, and to "earth" at one point in the circuit, preferably at the D.C. ground terminal of the unit.

3)Output lines - The unit has two relay outputs. When these outputs are used to run external relays or solenoids, spikes can be generated upon activation. This noise can spread through the instrument causing operating problems. If the source is a D.C. operated device, a general purpose diode (IN4004) placed across the solenoid prevents electrical noise spikes. Connect the cathode (banded side) to the more positive side of the coil. If the source is an A.C. operated device, use a MOV or Resistor Capacitor across the coil.

4)12 VDC output supply - Noise can be generated on the 12 VDC output supply if it is used to drive inductive loads or if the current draw exceeds 50 mA. Insure that all inductive loads have a diode (such as IN4004) across the coil and that the current does not exceed 50 mA.

UP/DOWN CONTROL AND QUADRATURE INPUTS

QUADRATURE INPUT:

When programming the counter section for quadrature input, you must set the unit for A net B and A sub B (see step 2 in programming section). This insures proper operation. The rate can only be viewed in one direction. If the unit is a ratemeter only (DPF78), connect only one of the quadrature channels to Input A (pin 5).

UP/DOWN CONTROL:

When using the up/down control option, Input A (pin 5) is the count input and Input B (pin 6) is the up/down control (direction) input. The counter must be set for A net B and A sub B (see step 2 in programming section).

When the direction input is high (4-30VDC) the count inputs will count up, when the direction input is low (open or less than 1VDC) the count inputs will count down. The direction input must precede the count input by 1 msec when the unit is set for low CPS and 1 usec when set for high CPS.

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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 DimensionsWiring UP/DOWN Control and Quadrature InputsQuadrature Input UP/DOWN ControlConnecting AC / DC Power Wiring Considerations Do not USE PIN 7 with These MetersWhat can YOU VIEW? Output Jumper Selections Millivolt Input Option=CLOSE, O=OPEN 30V InputProgram Programming FlowchartOperating the Front Panel Portion of Menu for Setting Counter Variables Portion of Menu for Setting Rate VariablesProgram Codes and Descriptions DescriptionTerminations Rear ViewCalculating Scale Factors Scaling Factor ExamplesProgramming PressRemarks ScalingSetting Counter PrgmSetting Rate Remarks DisplayLock SettingLock Remarks Press Setting RelaysPresets Analog Output Output WiringAlarms Analog Output Option DescriptionInterface Card RS 232/422 Operation Serial Input Commands Unit will Recognize a Decimal if ONE isPlaced in ANY of These Data Values †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