Danfoss vlt aqua Programming Guide

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
2

Danfoss vlt aqua Specifications

General

Supply Voltage	200-240V, 380-500V, 525-600V
Enclosure	IP20
Features	Energy optimization
Approvals	CE, UL, cUL
Input Voltage Range	200-240V, 380-500V, 525-600V
Output Voltage Range	0 to supply voltage
Protection Features	Overvoltage, Undervoltage, Overcurrent, Short circuit, Ground fault
Communication Interfaces	PROFIBUS
Cooling Method	Air-cooled