Capacitor Disconnect - Danfoss AHF 005 Operating Instructions Manual

4 Installation
Frame E
NB!
4
For UL approval use copper conductor only.

4.1.4 Capacitor Disconnect

The power factor of the harmonic filter AHF 005/010 is decreasing with decreasing load. At zero load the Power Factor becomes zero and the capacitors
produce approximately 30% leading current compared to the rated current of the filter. The reactive current generated by the filter at partial load is
normally not of any concern, mainly because of the small current compared to the system capacity (max. 30%) as well as the fact that other load normally
compensates the capacitive current.
Illustration 4.2: Power Factor as a function of load.
In applications where this reactive current may not be accepted, Terminals X3.1, X3.2, X3.3 and X4.1, X4, X4.3 are giving acces to the filter capacitors.
As default (on delivery) the wiring will shorten Terminal X3.1 with X4.1, X3.2 with X4.2 and X3.3 with X.4.3. In the case of that no capacitor disconnect
is required no changes should be made. If capacitor disconnect is required a three-phase contactor should be placed between terminals X3 and X4.
Size the contactor and wiring according to below table. It is recommended only to use contactors with damping resistors.
NB!
It is not allowed to use one common 3 poled contactor in several paralleled AHF at once to disconnect the capacitors.
18
Frame F
AH F 01 0
1
0,9
0,8
0,7
0,6
0,5
0,4
0,3
0,2
0,1
0
0 20 40
Load [%]
MG.80.C2.02 - VLT
AHF 005/010 Operating Instructions
60 80 100
®
is a registered Danfoss trademark
Frame G, Frame H