Monitor and control equipment
i-Vu CCN Pro 4.2
75
Field
Notes
Sample every _:_:_ (hh:mm)
This method records (samples) the point’s value at the time
interval you define in this field.
NOTE
Be sure to set trend intervals to one minute or greater.
Sample on COV
(change of value)
This method records the point’s value only when the value
changes by at least the amount you enter in the
COV Increment
field.
NOTE
Use this method for a binary point or for an analog point
that has infrequent changes in value.
Allocate memory for __ samples in the
module
Type the maximum number of samples to be stored in the
equipment.
NOTE
Trending consumes memory in the equipment. The amount
of memory available depends on the type of module. Each
trended point consumes 48 bytes of memory plus 10 bytes for
each trend sample. Each trend microblock consumes 416 bytes
of memory plus 10 bytes for each trend sample.
Click
Reset
to delete all samples currently stored in the
equipment.
The sample and memory allocation fields together define trend
data storage in the controller in terms of hours.
EXAMPLE
If you set these fields so that samples are collected
every 5 minutes for a maximum of 120 samples, the controller
will store 600 minutes (5 x 120) or 10 hours of trend data.
Stop When Full
Select this field to stop trend sampling when the maximum
number of samples is reached.
Enable trend log at specific times only?
Collects trend data for the specific period of time you define in
the
time
and
date
fields.
Enable Trend Historian
Archives trend data to the system database.
Store Trends Now
Writes all trend data in the controller to the system database
without having to enable trend historian.
Every __ trend samples write to historian
Writes all trend data in the equipment to the system database
each time the equipment collects the number of samples that
you enter in this field. This number must be greater than zero
and less than the number entered in the field
Allocate memory for
__ samples in the module
. The number of trends specified must be
accumulated at least once before the historical trends can be
viewed.
Trend samples accumulated since last
notification
Shows the number of samples stored in the controller since data
was last written to the database.
Last Record Written to Historian
Shows the last two times that trend data was written to the
database.
Keep historical trends
for __ days
This is based on the date that the sample was read. Set this field
to 0 to use the system default defined in System Settings
Delete
Deletes all trend samples stored in the database for the item
selected in the navigation tree.
