Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

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Ground Plane
LINE
FREQUENCY MOTOR CABLE SHIELDED
MOTOR
DRIVE
Ground wire
Shield
z
z
z
L1
L2
L3
PE
U
V
W
PE
175ZA062.11
C S
I 2
I 1
I 3
I 4
C S
C S
C S
C S
I 4
C S
z PE
Figure 2.30 Situation that Generates Leakage Currents
If the shield is to be placed on a mounting plate for the Adjustable frequency drive, the mounting plate must be made of
metal, because the shield currents have to be conveyed back to the unit. Moreover, ensure good electrical contact from the
mounting plate through the mounting screws to the Adjustable frequency drive chassis.
When non-shielded cables are used, some emission requirements are not complied with, although the immunity
requirements are observed.
In order to reduce the interference level from the entire system (unit + installation), make motor and brake cables as short
as possible. Avoid placing cables with a sensitive signal level alongside motor and brake cables. Radio interference higher
than 50 MHz (airborne) is especially generated by the control electronics. Please see for more information on EMC.
2.9.2 Emission Requirements
According to the EMC product standard for adjustable frequency drives EN/IEC 61800-3:2004 the EMC requirements depend
on the intended use of the Adjustable frequency drive. Four categories are defined in the EMC product standard. The
definitions of the four categories together with the requirements for line power supply voltage conducted emissions are
given in
Table 2.10 .
Category Definition
Conducted emission requirement
according to the limits given in EN
55011
C1 Adjustable frequency drives installed in the first environment (home and office) with
a supply voltage less than 1000 V. Class B
C2 Adjustable frequency drives installed in the first environment (home and office) with
a supply voltage less than 1000 V, which are neither plug-in nor movable and are
intended to be installed and commissioned by a professional. Class A Group 1
C3 Adjustable frequency drives installed in the second environment (industrial) with a
supply voltage lower than 1000 V. Class A Group 2
C4 Adjustable frequency drives installed in the second environment with a supply
voltage equal to or above 1000 V or rated current equal to or above 400 A or
intended for use in complex systems. No limit line.
An EMC plan should be made.
Table 2.10 Emission Requirements
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