Measurement Computing eZ-Balance rev.9.0 - Manual (Page 27)

eZ-Balance 969391 Windows, Buttons, and Menus 3-9
Configuration Window . . . Input Channels Tab
Attribute Comments
Integration
None
Single
Double
Accelerometer and velocity signals can be integrated. Select the desired integration type
[None, Single, or Double]. To do this, left-click on the cell and select the integration
type from the resulting list.
In regard to integrating acceleration and velocity:
. . . for Acceleration: single integration results in velocity.
double integration results in displacement.
. . . for Velocity: single integration results in displacement.
FSV
(Full Scale
Voltage) Select the maximum Full Scale Voltage that is expected for the instrument.
Erroneous results will occur if you select a voltage value that is less than the actual input
voltage. If you are unsure of the instrument’s maximum voltage value, select a high
voltage value [i.e.: +/-25V for displacement probes; +/- 5V for accelerometers and
velocity sensors.]
IEPE
(Integral
Electronics
Piezoelectric)
The Institute of Environmental Science and Technology adopted the term IEPE (Integral
Electronics Piezoelectric) to identify what had been commonly referred to as ICP
®
(Integrated Circuit Piezoelectric). The two terms are synonymous; however, ICP is
registered by PCB Pizeotronics.
A constant bias current is available for IEPE transducers that are used as signal input for
associated analog channels and for compatible expansion modules that accept IEPE
transducers, for example, the WBK18. The bias current is sourced through the center
conductor of the input channel BNC connector and returns to the acquisition device [e.g.,
ZonicBook/618E or the WBK18, or IOtech 600 Series device] via the BNC’s outer
conductor.
The current source features an operating compliance voltage (see specs) and is protected
in regard to both short-circuit and overvoltage. Operating compliance refers to the
highest voltage that can be applied without change of the current source value. For
applications that do not require bias, the current source can be disconnected from the
input by un-checking IEPE in the Input Channels tab on a per-channel basis.
Checking a channel’s IEPE cell enables the current source for that channel. With IEPE
enabled, level detection circuitry continuously monitors the channel’s input voltage.
Recognition of a voltage greater than 25V (transducer open) or less than 1V (transducer
short) triggers a transducer fault condition for the associated channel. This error is
communicated to the user via a front panel LED on some units (not on 600 Series) and is
also available through a software status request at the end of an acquisition. When
recognized, an error is latched until the commencement of a new acquisition.
Consequently, even intermittent faults are detected and communicated. Detection of a
fault does not, however, alter the acquisition process or its data.
When the IEPE function is not available to a channel a dash appears in the IEPE column
for the associated channel.