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25-42 Staging Threshold
Range:
Function:
90%
*
[0 – 100%]
When adding a fixed speed pump, in order to prevent an overshoot of pressure, the variable speed pump ramps
down to a lower speed. When the variable speed pump reaches the “Staging Speed” the fixed speed pump is
staged on. The Staging Threshold is used to calculate the speed of the variable speed pump when the “cut-in
point” of the fixed speed pump 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
η
STAGE % =
η
LOW
η
HIGH
× 100 %
to 100%, where n
LOW
is Motor Speed Low Limit and n
HIGH
is Motor Speed High Limit.
25-43 Destaging Threshold
Range:
Function:
50%
*
[0 – 100%]
When removing a fixed speed pump, in order to prevent an undershoot of pressure, the variable speed pump
ramps up to a higher speed. When the variable speed pump reaches the “Destaging Speed” the fixed speed pump
is destaged. The Destaging Threshold is used to calculate the speed of the variable speed pump when the de-
staging of the fixed speed pump occurs. The calculation of the Destaging 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.
Destaging Threshold must range from
η
STAGE % =
η
LOW
η
HIGH
× 100 %
to 100%, where n
LOW
is Motor
Speed Low Limit and n
HIGH
is Motor Speed High Limit.
VLT
®
HVAC Drive Programming Guide
3. Parameter Description
MG.11.C5.02 - VLT
®
is a registered Danfoss trademark
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