Danfoss VLT CDS302 Operating Instructions Manual page 115

Parameter Descriptions
activated, an alternation is carried out by ramping the
variable speed compressor to 4-13 Motor Speed High Limit
[RPM] or 4-14 Motor Speed High Limit [Hz], and then
decelerated to zero speed. After a "Delay Before Starting
Next Compressor" (25-58 Run Next Compressor Delay) the
next lead compressor (middle graph) is accelerated and
another original lead compressor (top graph) is added after
the "Delay Before Running On Mains" (25-59 Run on Mains
Delay) as a fixed speed compressor. The next lead
compressor (middle graph) is decelerated to Motor Speed
Low Limit and then allowed to vary speed to maintain
system pressure.
Illustration 6.37
25-58 Run Next Compressor Delay
Range: Function:
0.5 [25-58 Run This parameter is only active if the
sec Next Compressor option selected in 25-50 Lead
*
Delay – 5.0 sec] Compressor Alternation, is different
from [0] Off.
This parameter sets the time between
stopping the old variable speed
compressor and starting another
compressor as a new variable speed
compressor. Refer to 25-56 Staging
Mode at Alternation and Illustration 6.37
for description of staging and
alternation.
MG34M302 - VLT
®
Operating Instructions VLT
25-59 Run on Mains Delay
Range:
0.5
sec
*
6.14.5 25-8* Status
Readout parameters informing about the operating status
of the cascade controller and the compressors controlled.
25-80 Pack Status
Option:
Disabled
Emergency
Off
In Open Loop
Frozen
Jogging
Running
Running FSBW The frequency converter is tripped off and the
Staging
Destaging
Lead Not Set
®
is a registered Danfoss trademark/Commercial Compressor
CDS302 and CDS303
Function:
[25-58 Run This parameter is only active if the
Next Compressor option selected in 25-50 Lead
Delay – 5.0 sec ] Compressor Alternation, is different
from [0] Off.
This parameter sets the time between
stopping the old variable speed
compressor and starting this
compressor as a new fixed speed
compressor. Refer to 25-56 Staging
Mode at Alternation and Illustration 6.37
for description of staging and
alternation.
Function:
Read out of the status of the Pack Controller.
Pack Controller is disabled (25-00 Cascade
Controller).
All compressors have been stopped by means
of a Coast/Coast inverse or an External Interlock
command applied to the frequency converter.
All compressors have been stopped by means
of a Stop command applied to the frequency
converter.
1-00 Configuration Mode has been set for [0]
Open Loop. All fixed speed compressors are
stopped. The variable speed compressor will
continue to run.
Staging/destaging of compressors has been
locked and reference locked.
All fixed speed compressors are stopped. When
stopped, the variable speed compressor will run
at jog speed.
A Start command is applied to the frequency
converter and the Pack controller is controlling
the compressors.
Pack Controller is controlling the fixed speed
compressors based on 4-14 Motor Speed High
Limit [Hz].
The Pack Controller is staging fixed speed
compressors.
The Pack Controller is destaging fixed speed
compressors.
No compressor available to be assigned as
variable speed compressor.
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