Table 22. Analog Output Configuration (Continued)
GPIC Analog Output
SW21 Contact
AO6
7
AO7
8
Note
Analog outputs that are used outside the sbRIO-9687 should be disconnected
from onboard functionality.
Over-Range Comparators
The sbRIO-9687 interface board has eight over-range comparators that can be connected to
analog input signals. The over-range comparators are triggered if the absolute value of the
input is over the set voltage. For example, if the threshold is set at 7 V, then the over range is
triggered if the input is over 7 V or under -7 V.
The following figure is a block diagram for the over-range circuits.
Figure 14. Over-Range Circuit Block Diagram
Input
Connectors
Inverter
Connectors
Phase Current
DC Link Voltage
Over Range
Set Point
AO
DIO
GPIC
Configurable position
Over-Range
Comparators
CM
Filter
CM
Filter
Current-
Sensing
Resistor
CM
Filter
The eight over-range comparators can be connected to inverter phase current, inverter DC link
voltage, or to one of the 16 simultaneous sampled analog inputs. The over-range threshold can
be set using one of the GPIC analog outputs or by populating a resistor divider on the board.
The over-range output is an active low digital signal connected to the GPIC low voltage TTL
inputs.
Note
If any of the DIO lines (DIO0 to DIO7) are to be used for the extension
board, they should be disconnected from the onboard functionality by depopulating
the corresponding 0 Ω resistor. See
LVTTL Lines
on page 38 for details.
Over-Range Comparator Input Configuration
Over-range comparators are connected to the input source with a series of DIP switches.
Because all input signals are differential, a pair of contacts should be closed to select one
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sbRIO-9687 User Manual