3.21.4 23-6* Trending
Trending is used to monitor a process variable over a
period of time and record how often the data falls into
each of ten user-defined data ranges. This is a convenient
tool to get a quick overview indicating where to put focus
for improvement of operation.
Two sets of data for Trending can be created in order to
make it possible to compare current values for a selected
operating variable with data for a certain reference period,
for the same variable. This reference period can be pre-
programmed (
and
). The two sets of data can be read from
(current) and
(reference).
It is possible to create Trending for following operation
variables:
-
Power
-
Current
-
Output frequency
-
Motor Speed
The Trending function includes ten counters (forming a
bin) for each set of data containing the numbers of
registrations reflecting how often the operating variable is
within each of ten pre-defined intervals. The sorting is
based on a relative value of the variable.
The relative value for the operating variable is
Actual/Rated * 100%
for Power and Current and
Actual/Max * 100%
for Output Frequency and Motor Speed.
The size of each interval can be adjusted individually, but
will default be 10% for each. Power and Current can
exceed rated value, but those registrations will be included
in 90%-100% (MAX) counter.
Relative value
operating variable
Counter 1: +1
Counter 0: +5
Counter 2: +0
Counter 3: +1
Counter 4: +0
Counter 5: +11
Counter 6: +1
Counter 7: +2
Counter 8: +6
Counter 9: +0
130BA281.10
80
70
50
60
30
40
10
20
%
90
100
Once a second, the value of the operating variable
selected is registered. If a value has been registered to
equal 13%, the counter “10% - <20%” will be updated with
the value “1”. If the value stays at 13% for 10s, then “10”
will be added to the counter value.
The contents of counters can be displayed as bars on LCP.
Select
Quick Menu
>
Loggings
:
Trending Continued Bin /
Trending Timed Bin / Trending Comparison
.
NOTE
The counters starts counting whenever the frequency
converter is powered-up. Power cycle shortly after a reset
will zero the counters. EEProm data are updated once per
hour.
23-60 Trend Variable
Option:
Function:
Select the desired operating variable to be
monitored for Trending.
[0]
*
Power [kW]
Power yielded to the motor. Reference for
the relative value is the rated motor power
programmed in
or
. Actual value can be
read in
or
.
[1]
Current [A]
Output current to the motor. Reference for
the relative value is the rated motor current
programmed in
. Actual
value can be read in
.
[2]
Frequency
[Hz]
Output frequency to the motor. Reference
for the relative value is the maximum output
frequency programmed in
. Actual value can be read in
[3]
Motor Speed
[RPM]
Speed of the motor. Reference for relative
value is the maximum motor speed
programmed in
Parameter Description
VLT
®
HVAC Drive Programming Guide
166
MG.11.CC.02 - VLT
®
is a registered Danfoss trademark
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