Omega Speaker Systems PCI-DAS1002 PCI-DAS1000 and signal source already have isolated grounds

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Relying on the earth prong of a 120VAC for signal ground connections is not advised.. Different ground plugs may have large and potentially even dangerous voltage differentials. Remember that the ground pins on 120VAC outlets on different sides of the room may only be connected in the basement. This leaves the possibility that the “ground” pins may have a significant voltage differential (especially if the two 120 VAC outlets happen to be on different phases!)

PCI-DAS1000 and signal source already have isolated grounds

Some signal sources will already be electrically isolated from the PCI-DAS1000. The diagram below shows a typical isolated ground system. These signal sources are often battery powered, or are fairly expensive pieces of equipment (since isolation is not an inexpensive proposition), isolated ground systems provide excellent performance, but require some extra effort during connections to assure optimum performance is obtained. Please refer to the following sections for further details.

4.2 WIRING CONFIGURATIONS

Combining all the grounding and input type possibilities provides us with the following potential connection configurations. The combinations along with our recommendations on usage are shown in the chart below.

Ground Category

Input Configuration

Our view

Common Ground

Single-Ended Inputs

Recommended

 

 

 

Common Ground

Differential Inputs

Acceptable

 

 

 

Common Mode

Single-Ended Inputs

Not Recommended

Voltage < +/-10V

 

 

 

 

 

Common Mode

Differential Inputs

Recommended

Voltage < +/-10V

 

 

 

 

 

Common Mode

Single-Ended Inputs

Unacceptable without

Voltage > +/- 10V

adding Isolation

 

 

 

 

Common Mode

Differential Inputs

Unacceptable without

Voltage > +/-10V

adding Isolation

 

 

 

 

Already Isolated Grounds

Single-ended Inputs

Acceptable

 

 

 

Already Isolated

Differential Inputs

Recommended

Grounds

 

 

 

 

 

The following sections depicts recommended input wiring schemes for each of the 8 possible input configuration/grounding combinations.

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Contents Users Guide Table of Contents BADR0 BADR1 BADR2BADR3 BADR4Introduction Installation IntroductionRUN InstaCal DOS and/or WindowsConnector PIN Diagram Hardware ConnectionsAnalog Connections Single-Ended and Differential InputsSingle-Ended Inputs Differential Input Differential InputsSystem Grounds and Isolation Which system do you have?Systems with Common Mode ground offset Voltages Small Common Mode VoltagesLarge Common Mode Voltages PCI-DAS1000 and signal source already have isolated grounds Ground Category Input Configuration Our view    Board Board Programming & Software Applications SELF-CALIBRATION of the PCI-DAS1000 Analog InputsAnalog Outputs BADR0 BADR1Interrupt / ADC Fifo Register Region Function OperationsInte EoaieIntcl AdflclADC Channel MUX and Control Register BADR1 + CHL8-CHL1, CHH8-CHH1EOC Pacer Source= ADC Done = ADC Busy Trigger CONTROL/STATUS Register BADR1 + TS10ARM Fifo Mode Sample CTR C0SRCXtrig IndxgtCalibration Register BADR1 +DAC Channel Cal Function Cal SourceDacen Mode DAC CONTROL/STATUS Register BADR1 +DACnR10 DACnR1 DACnR0 Range LSB SizeBADR2 ADC Data Register BADR2 +ADC Fifo Clear Register BADR2 + MSB LSBBADR3 ADC Pacer Clock Data and Control RegistersBADR3 + Device Counter # FunctionADC 8254 Control Register Digital I/O Data and Control RegistersDIO Port a Data DIO Port B DataDIO Port C Data DIO Control RegisterPort a Port C Port B Upper Lower OUT Index and User Counter 4 Data and Control Registers 8254B Counter 1 Data User Counter #58254B Counter 2 Data User Counter #6 BADR3 + Ah8254B Control Register BADR3 + BhBADR4 1 DAC0 Data RegisterBADR4 + 2 DAC1 Data RegisterElectrical Specifications Analog Output Power consumption EnvironmentalEC Declaration of Conformity
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