4-2
|
ni.com
Chapter 4
Power Connections
outputs are isolated from the computer power supply and from one another. Isolated
photocouplers provide isolation.
Optically Isolated Inputs
(NI 6510/6511/6514/6515/651
8
/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
IN
) on these lines
is 30 V DC.
Sensing DC Voltages
(NI 6510/6511/6514/6515/6518/6519 only)
These devices can sense DC signals from 11 V to
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)
The following figures show signal connections for
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
ni.com/
manuals
, for information about voltage ranges.
Figure 4-1.
NI 6510 Signal Connection Example
+
3
.
3
V
P<0..
3
>.<0..7>
COM
NI 6510
0 V ~ +
3
0 V
or
0 V ~ –
3
0 V
AC Inp
u
t
Photoco
u
pler
