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[0]
Disabled
[1]
*
Enabled
25-30 Destage Function Time
Option:
Function:
[15 sec.]
*
0 – 300 sec.
The Destage Function Timer is programmable to avoid frequent staging/destaging of the fixed speed pumps.
The Destage Function Time starts when the adjustable speed pump is running at
Motor Speed Low Limit
, par.
4-11 or 4-12, with one or more fixed speed pumps in operation and system requirements satisfied. In this
situation, the adjustable speed pump contributes a little to the system. When the programmed value of the timer
expires, a stage is removed, avoiding dead head water circulation in the adjustable speed pump.
3.23.4. 25-4* Staging Settings
Parameters determining conditions for staging/destaging the pumps.
25-40 Ramp Down Delay
Range:
Function:
10 sec.
*
[0 – 120 sec. ]
When adding a fixed speed pump controlled by a soft starter, it is possible to delay the ramp down of the lead
pump until a preset time after the start of the fixed speed pump to eliminate pressure surges or water hammer
in the system.
Only to be used if
Soft Starter
[1] is selected in par. 25-02,
Motor Start
.
25-41 Ramp Up Delay
Range:
Function:
2 sec.
*
[0 – 120 sec.]
When removing a fixed speed pump controlled by a soft starter, it is possible to delay the ramp up of the lead
pump until a preset time after the stopping of the fixed speed pump to eliminate pressure surges or water hammer
in the system.
Only to be used if
Soft Starter
[1] is selected in par. 25-02,
Motor Start
.
3. Parameter Description
VLT
®
HVAC Drive Programming Guide
214
MG.11.C5.02 - VLT
®
is a registered Danfoss trademark
3