National Instruments NI 9219 Voltage and Current Modes

© National Instruments Corp. 13 NI 9219 Operating Instructions

Figure 5. Input Circuitry for One Channel

Voltage and Current Modes

In Voltage and Current modes, connect the signal source to the

NI9219 across the HI and LO terminals. The current is computed

from the voltage that the ADC measures across an internal shunt

resistor. Refer to Figure6 for an illustration of the connections.

Figure 6. Connections in Voltage, Current, and Digital In Modes

Isolated

ADC

TEDS

1

2

+

–

CHx3

6

NI 9219

FilterMUX

Current mode

HI

LO

ADC

IR

SH

NI 9219

Voltage/Digital In modes

HI

LO

ADC

V

+

–

NI 9219

Contents

Main Safety Guidelines Safety Guidelines for Hazardous Voltages Safety Guidelines for Hazardous Locations Special Conditions for Marine Applications Wiring the NI 9219 Page Page Connecting Wires to the NI 9219 Connectors Wiring TEDS Channels Grounding and Shielding Considerations Figure 3. Connecting a Grounded Signal Source to the NI 9219 Figure 4. Connecting a Floating Signal Source to the NI 9219 NI 9219 Timing Options NI 9219 Circuitry Figure 5. Input Circuitry for One Channel Voltage and Current Modes Figure 6. Connections in Voltage, Current, and Digital In Modes + 4-Wire Resistance and 4-Wire RTD Modes 3-Wire RTD Mode 2-Wire Resistance and Quarter-Bridge Modes Half-Bridge and Full-Bridge Modes Thermocouple Mode Digital In Mode Open Contact Mode Sleep Mode Binary Data Excitation Protection Specifications Input Characteristics Page Page Page Page Input noise in ppm of Range Page Page Power Requirements Physical Characteristics Safety Safety Voltages Safety Standards Hazardous Locations Environmental Shock and Vibration Electromagnetic Compatibility CE Compliance Waste Electrical and Electronic Equipment (WEEE) Calibration Where to Go for Support