©
National Instruments Corp.
9
NI 9478 Operating Instructions and Specifications
Protecting the Module from Flyback Voltages
If the mod
u
le is switching an ind
u
ctive or energy-storing device
s
u
ch as a solenoid, motor, or relay, and the device does not have
flyback protection, install an external flyback diode as shown in
Fig
u
re 3. Refer to the
section for more
information abo
u
t protection from cable ind
u
ctance flyback.
Figure 3.
Connecting a Flyback Diode to the NI 9478
+
–
NI 947
8
COM
DO
External
Power
S
u
pply
V
su
p
Cable
Clamp
Device
