©
National Instruments Corporation
5
SCC-ACC01 Accelerometer Input Module User Guide
Figure 1.
SCC-ACC01 Signal Connections
The signal source can be floating or ground-referenced. The SCC-ACC01
input circuitry includes high-impedance bias resistors typically required for
floating sources. External bias resistors connected to ground are not
required.
For floating signal sources in high-noise environments, connect the
negative terminal of the signal source to the AI GND terminal on the
SC-2345 screw-terminal block to reduce common-mode noise.
For information about how to configure the SCC-ACC01 module using
NI-DAQmx, refer to the
SCC Quick Start Guide
.
Using the SCC-ACC01
Scaling Voltage Measurements
If you configured the SCC-ACC01 using Measurement & Automation
Explorer (MAX) and are using NI-DAQ, the reading you get from the
E Series DAQ device is properly scaled. Use scaling constants obtained
from your sensor data sheet to convert the accelerometer voltage to the
desired unit, such as newtons, m/s
2
, or g. Otherwise, complete the
following steps to scale the readings:
1.
Measure the accelerometer voltage.
a.
Read the accelerometer channel on the E Series DAQ device
V
ESERIES
(CH
X
).
b.
Calculate the accelerometer voltage using this formula:
V
ACC
=
V
ESERIES
/2
where
V
ACC
is the SCC-ACC01 input voltage.
V
ESERIES
is the E Series DAQ device input voltage.
I
EX
(4 mA)
E Series
AI (
X
)
+
–
+
–
4
3
2
1
SCC-ACC01
ACC
AC
Coupling
19 kHz
Lowpass
Filter
