Galvanic Isolation (Pelv); Pelv - Protective Extra Low Voltage - GE AF-600 FP Design And Installation Manual

Installation Consideration
NOTE!
Some of the harmonic currents might disturb communi-
cation equipment connected to the same transformer or
cause resonance in connection with power-factor
correction batteries.
To ensure low harmonic currents, the adjustable frequency
drive is standard-equipped with intermediate circuit coils.
This normally reduces the input current I
The voltage distortion on the line power supply voltage
depends on the size of the harmonic currents multiplied
by the line power impedance for the frequency in
question. The total voltage distortion THD is calculated on
the basis of the individual voltage harmonics using this
formula:
THD U
% =
7 7
(U % of U)
N
7.3.1 Harmonics Emission Requirements
Equipment connected to the public supply network:
Options Definition
1 IEC/EN 61000-3-2 Class A for 3-phase balanced
equipment (for professional equipment only up to
1.5 hp [1 kW] total power).
2 IEC/EN 61000-3-12 Equipment 16A-75A and profes-
sional equipment as from 1.5 hp [1 kW] up to 16A
phase current.
Table 7.7
7.3.2 Harmonics Test Results (Emission)
Power sizes from 1 hp [0.75 kW] and up to 25 hp [18.5 kW]
in 200 V and up to 125 hp [90 kW] in 460 V complies with
IEC/EN 61000-3-12, Table 4. Power sizes 150–600 hp [110–
450 kW] in 460 V also complies with IEC/EN 61000-3-12
even though not required because currents are above 75
A.
Provided that the short-circuit power of the supply S
greater than or equal to:
S
3 ×
=
SC
3 × 120 × 400 ×
at the interface point between the user's supply and the
public system (R
7-6
RMS
2 2 2
U U
+ + ... +
N
5 7
R U I
× ×
SCE line power equ
I
equ
).
sce
AF-600 FP Design and Installation Guide
It is the responsibility of the installer or user of the
equipment to ensure, by consultation with the distribution
network operator if necessary, that the equipment is
connected only to a supply with a short-circuit power S
greater than or equal to that specified above.
Other power sizes can be connected to the public supply
network by consultation with the distribution network
operator.
by 40%.
Compliance with various system level guidelines:
The harmonic current data in the table are given in
accordance with IEC/EN61000-3-12 with reference to the
Power Drive Systems product standard. They may be used
as the basis for calculation of the harmonic currents'
influence on the power supply system and for the
documentation of compliance with relevant regional
guidelines: IEEE 519 -1992; G5/4.

7.4 Galvanic Isolation (PELV)

7.4.1 PELV - Protective Extra Low Voltage

PELV offers protection by way of extra low voltage.
Protection against electric shock is ensured when the
electrical supply is of the PELV type and the installation is
made as described in local/national regulations on PELV
supplies.
All control terminals and relay terminals 01-03/04-06
comply with PELV (Protective Extra Low Voltage) (Does not
apply to grounded Delta leg above 400 V).
Galvanic (ensured) isolation is obtained by fulfilling
requirements for higher isolation and by providing the
relevant creapage/clearance distances. These requirements
are described in the EN 61800-5-1 standard.
The components that make up the electrical isolation, as
described below, also comply with the requirements for
higher isolation and the relevant test as described in EN
61800-5-1.
The PELV galvanic isolation can be shown in six locations
(see Figure 7.3):
is
sc In order to maintain PELV, all connections made to the
control terminals must be PELV. For example, the
thermistor must be reinforced/double insulated.
=
1.
2.
DET-768A
Power supply (SMPS) incl. signal isolation of U
indicating the intermediate current voltage.
Gate drive that runs the IGBTs (trigger
transformers/opto-couplers).
sc
,
DC