Electrical Design And Installation; What This Chapter Contains - ABB PQFM Instruction Manual

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6 Electrical design and installation

6.1

What this chapter contains

This chapter gives the data required for integrating the PQFM active filter successfully
in an electrical installation. It also gives electrical connection examples for popular filter
options.
WARNING: The PQFM is able to operate on networks where the supply voltage is up to
10% higher than the equipment's rated voltage (inclusive of harmonics but not
transients). Since operation at the upper limits of voltage and temperature may
reduce its life expectancy, the PQFM should not be connected to systems for which it
is known that the overvoltage will be sustained indefinitely. Auxiliary circuits are
designed to operate in a +/- 10 % range of the equipment nominal auxiliary voltage
(230 Vrms, internally derived). Excessive (auxiliary) voltage levels may lead to filter
damage.
The active filter must be connected to the network in parallel with the loads.
Basic filter functionality can be obtained after connection of:
- Ground (PE) (per cubicle).
- Three power cables (per cubicle).
- 3 CTs (one per phase, to be connected to each filter unit in a filter system through
a daisy chain method with return path).
More advanced filter features (e.g. external monitoring of the filter status) require some
more connections. The connections for these advanced features have to be made on the
PQF-Manager. For IP00 filters, the PQF-Manager has to be firstly installed. Refer to
Section 5.6 for instructions on how to mechanically mount the PQF-Manager in a cubicle.
Refer to next section for information on how to connect the PQF-Manager electrically to
the filter system.
WARNING: Ensure that the filter supply is isolated upstream during filter installation.
If the system has been connected to the supply before, wait for 25 mins after
disconnecting the mains power in order to discharge the capacitors. Always verify by
measurement that the capacitors have discharged. DC capacitors may be charged to
more than 1000 Vdc.
The DC capacitors of PQFM units are automatically charged once the auxiliary circuit
is energized, regardless of whether the filter is switched off or not. Do not touch the
DC capacitor link when the auxiliary fuse box is closed.
42 Electrical design and installation ç Manual Power Quality Filter PQFM