Danfoss VLT CDS302, Operating Instructions Manual

Page: 121 / 161

28-43 DC Brake Cut-in Speed [RPM]
Range: Function:
700 RPM
‘0’ = Off
*
[0 – max
motor speed] Set the speed where the DC-brake
Current should cut in. The speed
must be higher than 0 RPM for the
DC-brake to activate before the
motor is coasted at 0 RPM to
prevent a reverse rotation.
6.15.6 28-5* Load Profile
The Load Profiler is used to get a graphical presentation of
the load pattern a cooling system has been subjected to
over the last 6 months. The system load is assumed to be
proportional to the compressor speed, and the Load
Profiler measures the load as the running hours spent
operating within certain speed intervals.
The speed intervals are calculated based on 4-11 Motor
Speed Low Limit [RPM] ( 4-13 Motor Speed High Limit [RPM] )
and 4-13 Motor Speed High Limit [RPM] ( 4-14 Motor Speed
High Limit [Hz] ) to match 0%, 25%, 50%, 75% and 100%
loads as good as possible. The speed intervals are denoted
“Off”, “Low”, “Med.”, “High” and “Full” and are calculated in
the following manner:
Δ = Motor Speed High Limit − Motor Speed Low Limit
Off : Speed = 0
Low :
Motor Speed Low Limit
≤
Speed
< Motor Speed Low Limit + Δ / 6
Med.
Motor Speed
Low Limit
+ Δ / 6 ≤
Speed
<
Motor Speed Low Limit
+ Δ / 2
High :
Motor Speed
Low Limit + Δ / 2 ≤ Speed < Motor Speed Low Limit + 5 × Δ / 6
Full :
Motor Speed
Low Limit
+ 5 × Δ / 6 ≤
Speed
≤
Motor Speed High Limit
For example, if 4-11 Motor Speed High Limit is 5400 RPM
and Motor Speed Low Limit is 1800 RPM the four calculated
intervals become
Low : 1800 RPM ≤ speed < 2350 RPM
Med : 2350 RPM ≤ speed < 3450 RPM
High : 3450 RPM ≤ speed < 4550 RPM
Full : 4550 RPM ≤ speed ≤ 5400 RPM
The profile is presented on the LCP as a histogram. In each
speed interval the indicated running time is accurate to
within 1 hour.
Illustration 6.40
The Load Profile is not updated if the Off key is pressed on
the LCP.
28-50 Reset Load Profile
Option: Function:
[0]
*
Do not reset No function
[1] Reset Clears the measured running time in all five
speed intervals.
28-74 Night Speed Drop [RPM]
Range: Function:
[] The value in this parameter will decrement the value in
4-13 Motor Speed High Limit [RPM] which becomes active
when night mode is activated.
Parameter Descriptions
Operating Instructions VLT
®
CDS302 and CDS303
MG34M302 - VLT
®
is a registered Danfoss trademark/Commercial Compressor 121
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