National Instruments SCXI-116 Series, Быстрый старт

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© National Instruments Corporation 19 SCXI Quick Start Guide
Frequently Asked Questions
My chassis is powered on, and my modules are configured for multiplexed mode, but I am
not getting good data on any channel. What is causing this problem?
The SCXI chassis has backplane fuses, fused at 1.5 A on the SCXI-1000 chassis and at 4 A on
the SCXI-1001 chassis. One or both of the fuses might be blown.
On the SCXI-1600, you can determine whether the fuses are blown by looking at the power
LEDs. Both power LEDs on the SCXI-1600 and the LED on the chassis must be lit. If any of the
LEDs are not lit, one or both fuses are blown.
On the SCXI-1000, the backplane fuses are located behind the fan. On the SCXI-1001, the
backplane fuses are located behind the right-hand fan, near the power entry module, as viewed
from the rear of the chassis.
Complete the following steps to examine and/or replace fuses.
1. Power off the chassis and remove the power cord.
2. Remove the four screws that secure the fan and filter to the rear of the chassis. When
removing the last screw, be careful to hold the fan to avoid breaking the fan wires.
3. To determine whether a fuse is blown, connect an ohmmeter across the leads. If the reading
is not approximately 0
Ω , replace the fuse. The fuse marked with a on the
backplane is for the positive analog supply, and the fuse marked with a copper – is for the
negative analog supply.
4. Using long-nose pliers, carefully remove the fuse.
5. Take a new fuse and bend its leads so the component is 12.7 mm (0.5 in.) long—the
dimension between the fuse sockets—and clip the leads to a length of 6.4 mm (0.25 in.).
6. Using long-nose pliers, insert the fuse into the socket holes.
7. Repeat steps 3 through 6, if necessary, for the other fuse.
8. Align the fan and filter with the fan holes, making sure that the label side of the fan is face
down. Reinstall the four screws and make sure the assembly is secure.
Refer to the chassis user manuals for fuse specifications.
My chassis worked until I inadvertently removed and reinserted a module while the chassis
was powered on. Now my chassis does not power on. What can I do?
SCXI modules are not hot-swappable, so you might have blown a chassis fuse. If replacing the
fuse does not correct the problem, you might have damaged the digital bus circuitry or the SCXI
module. Contact NI Technical Support at
ni.com/support
for assistance.
MAX does not recognize my chassis when I perform a test. What can I do?
Check the following items:
• Verify the chassis is powered on.
• Verify the chassis is correctly cabled to a DAQ device. If more than one DAQ device is
installed in your PC, verify the device selected for
Chassis Communicator is actually
connected to the chassis.
• Check backplane pins to determine if any were bent during installation of the modules.