Measurement Computing eZ-PostView rev.2.0 - Manual (Page 92)

4-14 Edit Menu 969795 eZ-Analyst
Configuring Analog Input Channels
Partial Column Headings for Analog Input Channels
No. This column lists the available analog input channels; for example, channels 1
through 8.
Active Initially all input channels are active. To set unused channels to OFF, remove the
check from the associated “Active” checkbox.
Label This should be a meaningful name. Highlight a cell before typing a label. When
you press the key, the button, or the button the label is
accepted.
Channel
Type*
This column applies to WaveBook and ZonicBook/618E systems. It does not
apply to ZonicBook Medallion. The column consists of a fixed label, which
indicates each channel’s parent hardware. Main unit channels, i.e., those that
connect directly to a WaveBook or ZonicBook/618E [as opposed to an expansion
module] are denoted by the label, “Direct”. Channel Type cannot be edited.
* The Channel Type column does not apply to ZonicBook Medallion applications.
Ref /
Resp
There are two types of channels, Reference and Response. All channels are
initialized as Response channels. If you are using a force channel, then (1)
highlight that channel’s Response/Reference cell, and (2) select Reference on the
resulting popup menu.
FSV Full-Scale Voltage. The cells in this column are used to set the FSV value in
Volts.
ICP
A constant 4mA bias current is available for ICP transducers that are used as
signal input for ZonicBook/618E’s analog channels (CH1 through CH8) and for
compatible expansion modules that accept ICP 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] via the BNC’s outer conductor.
The current source features an operating compliance of 24V 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.
In the absence of a transducer, the current source will output an open circuit
voltage of 30V. For applications that do not require bias, the current source can
be disconnected from the input by un-checking ICP in the Input Channels tab on
a per-channel basis.
When the ICP cell is checked for a channel, the current source is enabled, the
input voltage is continuously monitored with level detection circuitry. Recognition
of a voltage greater than 25V (transducer open) or less than 1V (transducer
short) triggers a transducer fault condition for the affected channel. This error is
communicated to the user via a front panel LED 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 ICP function is not available to a channel a dash appears in the ICP
column for the associated channel.