25-52 Alternation Time Interval
Range:
Function:
24 h
*
[1 – 999 h]
If
Alternation Time Interval
[1] option in
Alternation Event
, par.
25-51, is selected, the alternation of the variable speed pump
takes place every time the Alternation Time Interval expires
(can be checked out in
Alternation Timer Value
, par. 25-53).
25-53 Alternation Time Value
Option:
Function:
0 N/A
Readout parameter for the Alternation Time Interval value set
in par. 25-52.
25-54 Alternation Predefined Time
Range:
Function:
00:00
*
[00:00 – 23:59]
If option
Predefined Time
[3] in
Alternation Event
, par. 25-51, is
selected, the variable speed pump alternation is carried out ev-
ery day at the specified time set in Alternation Predefined Time.
Default time is midnight (00:00 or 12:00AM depending on the
time format).
25-55 Alternation if Capacity < 50%
Option:
Function:
[0]
Disabled
[1]
*
Enabled
If Alternation If Capacity <50% is enabled, the pump alternation
can only occurs if the capacity is equal to or below 50%. The
capacity calculation is the ratio of running pumps (including the
variable speed pump) to the total number of available pumps
(including variable speed pump, but not those interlocked).
Capacity
=
N
RUNNING
N
TOTAL
× 100 %
For the Basic Cascade Controller all pumps are equal size.
Disabled
[0]: The lead pump alternation will take place at any
pump capacity.
Enabled
[1]: The lead pump function will be alternated only if
the numbers of pumps running are providing less than 50% of
total pump capacity.
Only valid if par. 25-50,
Lead Pump Alternation
is different from
Off
[0].
25-56 Staging Mode at Alternation
Option:
Function:
[0]
*
Slow
[1]
Quick
This parameter is only active if the option selected in
Lead Pump
Alternation
, par. 25-50, is different from
Off
[0]
Two types of staging and destaging of pumps are possible. Slow
transfer makes staging and destaging smooth. Quick Transfer
VLT
®
AQUA Drive Programming Guide
2. Parameter Description
MG.20.O2.02 - VLT
®
is a registered Danfoss trademark
239
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