Danfoss VLT HVAC Series, Programming Manual, Page: 147 / 338

3.13.3 13-1* Comparators
Comparators are used for comparing continuous variables (i.e., output frequency, output current, analog input, etc.) to fixed preset values. In addition,
there are digital values that will be compared to fixed time values. See explanation in par.13-10
Comparator Operand . Comparators are evaluated once
in each scan interval. Use the result (TRUE or FALSE) directly. All parameters in this parameter group are array parameters with an index of 0 to 5. Select
index 0 to program Comparator 0, select index 1 to program Comparator 1, etc.
13-10 Comparator Operand
Array [4]
Option: Function:
Select the variable to be monitored by the comparator.
[0] * DISABLED
[1] Reference
[2] Feedback
[3] Motor speed
[4] Motor current
[5] Motor torque
[6] Motor power
[7] Motor voltage
[8] DC-link voltage
[9] Motor thermal
[10] VLT temp.
[11] Heat sink temp.
[12] Analog input AI53
[13] Analog input AI54
[14] Analog input AIFB10
[15] Analog input AIS24V
[17] Analog input AICCT
[18] Pulse input FI29
[19] Pulse input FI33
[20] Alarm number
[30] Counter A
[31] Counter B
13-11 Comparator Operator
Array [6]
Option: Function:
[0] * < Select < [0] for the result of the evaluation to be TRUE, when the variable selected in par.
13-10
Comparator Operand
is smaller than the fixed value in par.13-12
Comparator Value
. The result
will be FALSE, if the variable selected in par.13-10
Comparator Operand
is greater than the fixed
value in par.13-12
Comparator Value
.
[1] = (equal) Select ≈ [1] for the result of the evaluation to be TRUE, when the variable selected in par.
13-10 Comparator Operand is approximately equal to the fixed value in par.13-12 Comparator Val-
ue .
[2] > Select > [2] for the inverse logic of option < [0].
VLT ® HVAC Drive Programming Guide 3 Parameter Description
MG.11.C6.22 - VLT ® is a registered Danfoss trademark
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