Pelv - Protective Extra Low Voltage - Danfoss FC 300 Design Manual

FC 300 Design Guide
See following EMC immunity form.
Voltage range: 200-240 V, 380-480 V
Basic standard
Acceptance criterion
Line
Motor
Brake
Load sharing
Control wires
Standard bus
Relay wires
Application and Fieldbus op-
tions
LCP cable
External 24 V DC
Enclosure
AD: Air Discharge
CD: Contact Discharge
CM: Common mode
DM: Differential mode
1. Injection on cable shield.
Table 3.2: Immunity

3.6.1 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 illustration):
In order to maintain PELV all connections made to the control terminals must be PELV, e.g. thermistor must be reinforced/double insulated.
1. Power supply (SMPS) incl. signal isolation of U
intermediate current voltage.
2. Gate drive that runs the IGBTs (trigger transformers/opto-cou-
plers).
3. Current transducers.
4. Opto-coupler, brake module.
5. Internal inrush, RFI, and temperature measurement circuits.
6. Custom relays.
The functional galvanic isolation (a and b on drawing) is for the 24 V back-up option and for the RS 485 standard bus interface.
Burst Surge
IEC 61000-4-4 IEC 61000-4-5
B B
2 kV/2 Ω DM
4 kV CM
4 kV/12 Ω CM
4 kV CM 4 kV/2 Ω 1)
4 kV CM 4 kV/2 Ω 1)
4 kV CM 4 kV/2 Ω 1)
2 kV CM 1)
2 kV/2 Ω
2 kV CM 1)
2 kV/2 Ω
2 kV CM 1)
2 kV/2 Ω
2 kV CM
2 kV/2 Ω 1)
2 kV CM 1)
2 kV/2 Ω
0.5 kV/2 Ω DM
2 kV CM
1 kV/12 Ω CM
— —
, indicating the
DC
MG.33.BC.02 - VLT ® is a registered Danfoss trademark
3 Introduction to AutomationDrive FC 300
ESD Radiated electromagnetic field
IEC IEC 61000-4-3
61000-4-2
B A
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
8 kV AD
10 V/m
6 kV CD
Illustration 3.5: Galvanic isolation
RF common
mode voltage
IEC 61000-4-6
A
10 V
RMS
10 V
RMS
10 V 3
RMS
10 V
RMS
10 V
RMS
10 V
RMS
10 V
RMS
10 V
RMS
10 V
RMS
10 V
RMS
—
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