25-31 Stage Function
Option:
Function:
[0] *
Disabled
[1]
Enabled
If the Stage Function is set to
Disabled
[0],
Stage Timer
, par. 25-32, will not be activated.
25-32 Stage Function Time
Range:
Function:
15 sec.*
[0 – 300 sec.]
The Stage Function Time is programmed to avoid frequent staging of the fixed speed compressors.
The Stage Function Time starts if it is
Enabled
[1] by
Stage Feature
, par. 25-31, and when the
variable speed compressor is running at
Motor Speed High Limit
, par. 4-13 or 4-14 (or at Motor
Speed Low Limit par. 4-11 or 4-12 if par. 7-30 Process PID Normal/Inverse Control is programmed
to Inverse), with at least one fixed speed compressor in the stop position. When the programmed
value of the timer expires, a fixed speed compressor is staged.
25-33 Destage Function
Option:
Function:
[0] *
Disabled
[1]
Enabled
The Destage Function ensures that the lowest numbers of compressors are running to save energy.
If the Destage Function is set to
Disabled
[0], the
Destage Timer
, par. 25-34, will not be activated.
25-34 Destage Function Time
Range:
Function:
15 sec.*
[0 – 300 sec. ]
The Destage Function Timer is programmable to avoid frequent staging/destaging of the fixed speed
compressors. The Destage Function Time starts when the adjustable speed compressor is running
at
Motor Speed Low Limit
, par. 4-11 or 4-12 (or at Motor Speed High Limit par. 4-13 or 4-14 if par.
7-30 Process PID Normal/Inverse Control is programmed to Inverse), with one or more fixed speed
compressors in operation and system requirements satisfied. In this situation, the adjustable speed
compressor contributes little to the system. When the programmed value of the timer expires, a
stage is removed.
3.19.5 25-4* Staging Settings
Parameters determining conditions for staging/destaging the compressors.
25-42 Staging Threshold
Range:
Function:
90%*
[0 – 100%]
When adding a fixed speed compressor, in order to prevent an overshoot of pressure, the variable
speed compressor ramps down to a lower speed. When the variable speed compressor reaches the
“Staging Speed” the fixed speed compressor is staged on. The Staging Threshold is used to calculate
the speed of the variable speed compressor when the “cut-in point” of the fixed speed compressor
occurs. The calculation of the Staging Threshold is the ratio of
Motor Speed Low Limit
, par. 4-11 or
4-12, to the
Motor Speed High Limit
, par. 4-13 or 4-14, expressed in percent.
Staging Threshold must range from
ADAP-KOOL
®
Drive Programming Guide
3 Parameter Description
MG.11.N1.02 - VLT
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is a registered Danfoss trademark
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3