
© National Instruments Corporation 17 NI 6509 User Guide and Specifications
Figure 6. Limiting Flyback Voltages at the Inductive Load
Sinking and Sourcing ExamplesThe following sections provide examples of driving a relay less than
24 mA, driving a relay greater than 24 mA, and driving solid-state relays.
Driving a Relay <24 mAFigures7 and 8 show examples of connecting the NI 6509 to a relay that
does not require more than 24 mA of current.
Figure 7. NI 6509 Sinking Connection Example, <24 mA
Figure 8. NI 6509 Sourcing Connection Example, <24 mA
P
X
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Y
GND
Load
NI 6509 Flyback Diode for
Inductive Loads
P
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Y
GND
NI 6509
Vcc
P
X
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Y
GND
NI 6509