Lead Pump Alternation; Alternation Event; Alternation Time Interval; Alternation Timer Value - Danfoss VLT Programming Manual

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VLT HVAC Drive Programming Guide

25-50 Lead Pump Alternation

Option:
[0] * Off
[1] At staging
[2] At command
[3] At staging or command
NB!
It is not possible to select other than

25-51 Alternation Event

Option:
[0] * External
[1]

Alternation Time Interval

[2] Sleep Mode
[3] Predefined Time
25-52 Alternation Time Interval
Range:
24 h* [1 - 999 h]

25-53 Alternation Timer Value

Range:
0 N/A* [0 - 0 N/A]
25-54 Alternation Predefined Time
Range:
Application [Application dependant]
dependent*
Function:
Lead pump alternation equalizes the use of pumps by periodically changing the pump that is speed
controlled. This ensures that pumps are equally used over time. Alternation equalizes the usage of
pumps by always choosing the pump with the lowest number of used hours to stage on next.
No alternation of lead pump function will take place. It is not possible to set this parameter to options
other that Off [0] if par. 25-02 Motor Start
Alternation of the lead pump function will take place when staging another pump.
Alternation of the lead pump function will take place at an external command signal or a pre-pro-
Alternation Event
grammed event. See par. 25-51
Alternation of the variable speed (lead) pump will take place at staging or the "At Command" signal.
(See above.)
Off [0] if par. 25-05 Fixed Lead Pump
Function:
This parameter is only active if the options
Lead Pump Alternation
been selected in par. 25-50
nation of lead pump takes place every time the event occurs.
Alternation takes place when a signal is applied to one of the digital inputs on the terminal strip and
this input has been assigned to Lead Pump Alternation
puts .
Alternation takes place every time par. 25-52
Alternation takes place each time the lead pump goes into sleep mode. par. 20-23
Sleep Mode
be set to [1] or an external signal applied for this function.
Alternation takes place at a defined time of the day. If par. 25-54
set, the alternation is carried out every day at the specified time. Default time is midnight (00:00
or 12:00AM depending on the time format).
Function:
If Alternation Time Interval [1] option in par. 25-51
of the variable speed pump takes place every time the Alternation Time Interval expires (can be
checked out in par. 25-53 Alternation Timer Value
Function:
Readout parameter for the Alternation Time Interval value set in par. 25-52
terval .
Function:
Predefined Time
If option [3] in par. 25-51
alternation is carried out every day at the specified time set in Alternation Predefined Time. Default
time is midnight (00:00 or 12:00AM depending on the time format).
MG.11.C9.02 - VLT ® is a registered Danfoss trademark
3 Parameter Description
is set other than Direct on Line [0].
for available options.
is set to Yes [1].
At Command [2] or At Staging or Command
. If an Alternation Event is selected, the alter-
[121] in parameter group 5-1*, Digital In-
Alternation Time Interval
, expires.
Alternation Predefined Time
Alternation Event , is selected, the alternation
).
Alternation Event
, is selected, the variable speed pump
3
[3] have
Setpoint 3
must
, is
Alternation Time In-
249