Dead Band Around Zero - Danfoss VLT AutomationDrive FC 300 Design Manual

Introduction
P1 = (Minimum input value, Minimum reference value)
Minimum reference value
3 3
Minimum input value
P2 = (Maximum input value, Maximum reference value)
Maximum reference value
Maximum input value
Table 3.3 Parameters Defining the Endpoints P1 and P2 depending on which Analog or Pulse Input is used

3.3.4 Dead Band Around Zero

In some cases the reference (in rare cases also the
feedback) should have a Dead Band around zero (i.e. to
make sure the machine is stopped when the reference is
"near zero").
To make the dead band active and to set the amount of
dead band, the following settings must be done:
•
Either Minimum Reference Value (see Table 3.3 for
relevant parameter) or Maximum Reference Value
must be zero. In other words; Either P1 or P2
must be on the X-axis in Illustration 3.15.
•
And both points defining the scaling graph are in
the same quadrant.
The size of the Dead Band is defined by either P1 or P2 as
shown inIllustration 3.15.
26
RSPSupply - 1-888-532-2706 - www.RSPSupply.com
http://www.RSPSupply.com/p-21462-Danfoss-131B8966-VLT-Automation-VT-Drive-VFD-FC301-230V-5-HP.aspx
®
VLT AutomationDrive FC 300 Design Guide, 0.25-75 kW
Analog 53 Analog 53
S201=OFF S201=ON
6-14 Terminal 6-14 Terminal 53
53 Low Ref./ Low Ref./Feedb.
Feedb. Value Value
6-10 Terminal 6-12 Terminal 53
53 Low Voltage Low Current
[V] [mA]
6-15 Terminal 6-15 Terminal 53
53 High Ref./ High Ref./Feedb.
Feedb. Value Value
6-11 Terminal 6-13 Terminal 53
53 High High Current
Voltage [V] [mA]
®
MG33BE02 - VLT
Analog 54 Analog 54
S202=OFF S202=ON
6-24 Terminal 6-24 Terminal 54
54 Low Ref./ Low Ref./Feedb.
Feedb. Value Value
6-20 Terminal 6-22 Terminal 54
54 Low Low Current
Voltage [V] [mA]
6-25 Terminal 6-25 Terminal 54
54 High Ref./ High Ref./Feedb.
Feedb. Value Value
6-21 Terminal 6-23 Terminal 54
54 High High
Voltage[V] Current[mA]
Quadrant 2 Resource output
(RPM)
High reference/feedback
1500
value
Low reference/feedback
value
-10 -6
-1500
Quadrant 3
Illustration 3.15 Dead Band
is a registered Danfoss trademark
Pulse Input 29 Pulse Input 33
5-52 Term. 29 5-57 Term. 33 Low
Low Ref./Feedb. Ref./Feedb. Value
Value
5-50 Term. 29 5-55 Term. 33 Low
Low Frequency Frequency [Hz]
[Hz]
5-53 Term. 29 5-58 Term. 33 High
High Ref./ Ref./Feedb. Value
Feedb. Value
5-51 Term. 29 5-56 Term. 33 High
High Frequency Frequency [Hz]
[Hz]
Quadrant 1
P2
Resource
input
0 P1
(V)
-1 1 6 10
Terminal X Terminal X
low high
Quadrant 4