NI 9751 User Manual | © National Instruments | 25
INJ- shorted to battery—This condition immediately causes a ShortCircuit critical fault.
Because current is bypassing the injector solenoid, current rise times are extremely fast and can
peak as high as 200 A before detection. However, the NI 9751 can handle this current spike and
shut down appropriately.
INJ+ shorted to ground—This condition causes a HighVoltageDriver critical fault or
LowVoltageDriver critical fault during an injection event. The fault reported depends on whether
the short condition occurs during the high-voltage or low-voltage portion of the current profile.
INJ- shorted to ground—This condition causes a HighVoltageDriver critical fault or
LowVoltageDriver critical fault during an injection event. The fault reported depends on whether
the short condition occurs during the high-voltage or low-voltage portion of the current profile.
INJ+ shorted to INJ-—This condition causes a HighVoltageDriver critical fault or
LowVoltageDriver critical fault during an injection event. The fault reported depends on whether
the short condition occurs - during the high-voltage or low-voltage portion of the current profile.
INJ+/INJ- Open Circuit—The NI 9751 detects this condition when the current during the
injection event does not exceed 1.5 A. The NI 9751 reports the OpenCircuit non-critical fault for
the appropriate channel and automatically clears the Open Circuit upon the next pulse if the
condition is removed.
Connecting Injectors to the Module
Figure 32 illustrates connecting solenoid injectors to your NI 9751.
Figure 32. Connecting Solenoid Injectors to the NI 9751
Caution Fuse in Figure 32 is user-supplied and required in all instances.
NI 9751
INJ3–
INJ2+
INJ2–
INJ1+
INJ1–
BATT
INJ3+
GND
Solenoid
Injector
Solenoid
Injector
Solenoid
Injector
or
UL Listed 20 A
Automotive Fuse
12 V to 24 V
Ty pi cal,
150 W
+
+
+
–
–
–
+
–
+
–
To Next Page
Loading...
Need help?
General
