Danfoss AAF 007 Guia De Instalacion página 8

Advanced Active Filter AAF 007
Installation Guide
b. Checking correct polarity of CT cables: S1 to CTX and S2 to groundX (refer to step 7 in the Illustrations section).
c.
- Checking correct order of CT to filter terminals: L1:CTA, L2:CTB, L3:CTC. L2:CTB is only required for 4-wire systems
with neutral.
- d. Checking correct sequence of grid phases installation.
- e. Ensuring the right position of the CT according to the setting in the filter. Load side or grid side.
Routing of wires: The wires between AAF 007 and the current transformers must be twisted pair cables. A correct
function is only possible if the wiring exactly matches the upper diagram in step 7 in the Illustrations section. If
wires are interchanged, the harmonics are not to be reduced, but amplified. To avoid interchanging of wires, do
not use any wire color twice.
7.
When the filter is connected to mains, it will start operation. Check that the wiring is correct by assessment of the improve-
ment of the power quality either with the PC tool for filter or with a power quality meter. Consult the operating guide for
further information.
1.7 Parallel Installation
It is possible to install the filter modules in parallel to increase the filters' output current. If filter modules are installed in parallel, 1
CT set could be used for all parallel filter modules. Wire the CT's secondary wires in series from the CT to filter module 1, to module
2, to module X, and back to the CT terminals S2 or I, see step 1 in the Illustrations section.
For correct wiring of the current transducer when having 2 filters, refer to step 5 in the Illustrations section.
For correct wiring of the current transducer when having more than 2 filters, refer to step 6 in the Illustrations section. Ensure that
the CT configuration is configured to "series" (default) when applying series connection of CTs as described in steps 5 and 6 in the
Illustrations section.
Refer to step 2 in the Illustrations section for correct clearance distances what ensures correct operation in respect to thermal and
electro-magnetic considerations.
1.8 Current Transducers
The Advanced Active Filter AAF 007 needs extra current transducers (CTs). The possible installations of the CTs are on the mains
side/closed loop, which measures the mains current, including the filter output current, and on the load side/open loop, which
measures just the load current without the filter current.
On both settings, a CT is required. A CT set consists of 2 CTs. A 3-phase 3-wire system has 3 conductors but just 2 phase currents/
conductors are measured with CTs on phase L1 and phase L3. Phase 2 is calculated internally. If 3 CTs are already existing, only
phases L1 and L3 has to be connected to the filter.
If the current transducers are already in the installation or are ordered separately to the filter, ensure that they meet the following
specifications to guarantee the expected performance of the filter:
• Minimum burden 2.5 VA
• Minimum accuracy class 0.5
• 5 A secondary current
The cross-section of the wires has a significant influence on the quality of the control. If the cross-section is too small in relation to
the wire length, the resulting measurement will be too small to achieve a good control quality and good reduction of harmonics.
2
2 × d × v × I × ρ
A =
S
The following values need to be known:
• S = Power of the current transformer (typically 2.5 VA)
• d = Distance (length of cableway) between filter and current transformer
• v = Twisting factor (typically 1.5)
• I = Secondary current of the current transformer (typically 5 A)
• ρ = Rho = Specific resistance of copper (0.01786
2
Ω × mm
m
)
Example:
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Installation
AN43084697267901-000101 / 130R1374