Micromod Micro-PWC: 53PW6000 MicroPWC Configuration Guide - Manual (Page 255)

Micro-PWC CONFIGURATION GUIDE
Historical Database 235
5.3 Summary - Historical Database
Historical
Database Used to store data collected from the Micro-PWC server real-time tag
database; this data is used by various applications such as logging, trending
and data archiving.
Acknowledge
Bit Event bit used to confirm that a collection operation has been completed in the
historical database. When this bit is set, it is toggled from its current state to the
alternate state (i.e., from 1 to 0 or from 0 to 1).
Active Value Defines the state of the event bit (zero or one) which triggers a collection; the
face of the active value button displays the selected value. This parameter is
relevant only when the event bit is used.
Archive Group Set of data which is scheduled for archiving at a specified time. (The name and
scheduling information for archive groups is configured using Menu > Config-
ure > Archival Groups; refer to
Section 2.3, Archival Groups , for details.)
The face of the archive group button displays the name of the currently
assigned archive group. If no archive group has been assigned, it displays the
legend None. To assign the currently selected historical database point to an
archive group, click this button, then select the name of the desired archive
group in the resulting window. The default selection is None.
Collection
Option Defines the form in which collected values are stored. Available collection
options are average, minimum, maximum and instantaneous. The default
option is AVG; to change the option, click the button which displays the current
collection option; a new collection option can be selected from the resulting
window.
Collection Rate Interval between collections, the frequency with which data is gathered from an
associated point in the Micro-PWC server. The default collection rate is one
minute. Valid collection rates range from one second to one day, plus three
additional options: None, Manual, and Custom.
None is used when collection is based on an event condition, rather than a
time interval. Manual is used when data is to be entered manually, such as lab
data. Custom allows the user to define a custom time interval other than the
standard intervals supplied.
Computations The Micro-PWC can be configured to perform computations on data as it is col-
lected. Available calculations are: average, minimum, maximum and standard
deviation. Computations can be performed hourly, daily, weekly or yearly. The
computed values are stored in Historical Computation atoms, which can be
accessed by other applications, such as trending. Atoms are also available to
store the timestamp of the first instance of the minimum and maximum collec-
tion values.