Optically Isolated Inputs (Ni 6510/6511/6514/6515/6518/6519); Sensing Dc Voltages; Input Signal Connection Example - National Instruments NI PCI-6510 User Manual

Chapter 4 Power Connections
outputs are isolated from the computer power supply and from one another. Isolated
photocouplers provide isolation.
Optically Isolated Inputs
(NI 6510/6511/6514/6515/6518/6519)
The input lines provide 32 lines of optically isolated digital input on the NI 6510/6514/6515
device, 64 lines of optically isolated digital input on the NI 6511 device, and 16 lines of optically
isolated digital input on the NI 6518/6519 device. These inputs contain an AC input
photocoupler and a resistor for current limiting. The maximum input voltage (V
is 30 V DC.

Sensing DC Voltages

(NI 6510/6511/6514/6515/6518/6519 only)
DC power supply levels up to 30 V.
Applying a DC voltage of at least 11 V across the two input terminals registers a logic high for
that input. If no voltage is present (a voltage of 4 V or less), the device registers a logic low for
that input. DC voltages between 4 V and 11 V are invalid and register an unreliable value.

Input Signal Connection Example

(NI 6510/6511/6514/6515/6518/6519 only)
a supply connected to an isolated input on these devices. The power supply can be any DC
voltage within the device range. Refer to the NI 651x Specifications, available at
, for information about voltage ranges.
manuals
0 V ~ +30 V
or
0 V ~ –30 V
4-2 | ni.com
Figure 4-1. NI 6510 Signal Connection Example
P<0..3>.<0..7>
COM
These devices can sense DC signals from 11 V to
The following figures show signal connections for
AC Input
Photocoupler
NI 6510
) on these lines
IN
ni.com/
+3.3 V