SCXI-1327 Installation Guide
4
ni.com
When connecting or disconnecting signal lines to the SCXI terminal block screw terminals,
make sure the lines are powered off. Potential differences between the lines and the SCXI
ground can create a shock hazard while you connect the lines.
Connections, including power signals to ground and vice versa, that exceed any of the
maximum signal ratings on the SCXI device can create a shock or fire hazard, or can
damage any or all of the boards connected to the SCXI chassis, the host computer, and the
SCXI device. National Instruments is
not
liable for any damages or injuries resulting from
incorrect signal connections.
If hazardous voltages (
≥
30 V
rms
and 42.4 V
peak
or 60 VDC) are present, you
must
connect
a safety earth-ground wire to the terminal block safety-ground lug, shown in Figure 1. This
complies with safety agency requirements and protects against electric shock when the
terminal block is not connected to the chassis. To connect the safety earth-ground to the
safety-ground lug, run an earth-ground wire from the signal source to the terminal block.
National Instruments is
not
liable for any damages or injuries resulting from inadequate
safety earth-ground connections.
Do
not
loosen or re-orient the safety-ground lug hardware when connecting the
safety-ground wire; to do so reduces the safety isolation between the high voltage and
safety ground.
Clean the module and accessories by brushing off light dust with a soft non-metallic brush.
Remove other contaminants with a stiff non-metallic brush. The unit
must
be completely
dry and free from contaminants before returning it to service.
The terminal block
must
be used with a UL-listed SCXI chassis.
Configuring the High-Voltage Attenuator
Each channel has a 100:1 high-voltage attenuator that you can enable or
disable by changing switch settings as shown in Table 1. Each channel
requires two switches that you must set in the same position for the
attenuator to operate correctly. The switches are behind their corresponding
terminals.
•
Set both switches to the 100:1 position to attenuate the appropriate
channel. This setting places a precision 100:1 divider in the circuit to
divide the voltage by 100 before the voltage enters the module.
•
Set both switches to the 1:1 position to bypass the attenuator of the
appropriate channel. This setting removes the 100:1 divider from the
input stage.
Summary of Contents for SCXI-1327
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