Calculation Of The Exact Filter Size Needed - Danfoss AHF 005 Manual

Ordering numbers, 690 V 50 Hz
I Typical Motor
AHF,N
Used [kW]
43 A
72 A
101 A
144 A
180 A
217 A
289 A
324 A
370 A
Please note that the matching of the typical Danfoss adjustable frequency drive and filter is pre-calculated
based on 500V and assuming typical motor load. VLT 5000 series is based on a 160 % torque application,
while the VLT 8000 series are based on 110% torque application.
The pre-calculated filter current may vary from the input current ratings of VLT 5000 and VLT 8000 series as
stated in the respective instruction manuals, as these numbers are based on different operating conditions.

Calculation of the exact filter size needed

For optimal performance, the harmonic filter should
be sized for the line input current to the adjustable
frequency drive, i.e. the input current drawn based on
the expected load of the adjustable frequency drive
and not the size of the adjustable frequency drive itself!
The line input current to the adjustable frequency
drive (I ) can by calculated using the nominal motor
FC,L
current (I ) and displacement power factor (Cos
M,N
φ)) of the motor. Both data are normally printed
on the nameplate of the motor. In the case where
the nominal motor voltage (U
actual line-line voltage (U
6
Danfoss ordering number
AHF 005
37, 45 130B2328
55, 75 130B2330
90 130B2331
110, 132 130B2333
160 130B2334
200 130B2335
250 130B2331 &
130B2333
315 130B2333 &
130B2334
400 130B2334 &
130B2335
) is unequal to the
M,N
), the calculated current
L
Typical Danfoss adjustable frequency
AHF 010 VLT 5000 160 %
130B2293 5042, 5052
130B2295 5062, 5072
130B2296
130B2298 5122, 5152
130B2299
130B2300
130B2301
130B2302
130B2304
must be corrected with the ratio between these
voltages as shown in the equation below.
The harmonic filter chosen must have a nominal current
(I ) equal to or larger than the calculated adjustable
AHF,N
frequency drive line input current (I
If several adjustable frequency drives are to
be connected to the same filter, the harmonic
filter must be sized according to the sum of
the calculated line currents.
If the harmonic filter is sized for the load, and
the motor of the corresponding adjustable
frequency drive is changed, the current must
be re-calculated to avoid overload of the harmonic filter.
MG.80.B4.22 - VLT is a registered Danfoss trademark
AHF 005/010
drive series
VLT 8000 HVAC
8052
8062, 8072
5102 8102
8122, 8152
5202 8202
5252 8252
5302 8302
5352 8352
8402
).
FC,L