3.4.11 Mains Disconnects
Frame size Power & Voltage Type
D P132-P200 380–500 V OT400U12-9 or ABB OETL-NF400A
E P250 380-500 V ABB OETL-NF600A
E P315-P400 380-500 V ABB OETL-NF800A
F P450 380-500 V Merlin Gerin NPJF36000S12AAYP
F P500-P630 380-500 V Merlin Gerin NRK36000S20AAYP
Table 3.9 Recommended Mains Disconnects
3.4.12 F-Frame Circuit Breakers
Frame size Power & Voltage Type
F P450 380-500 V Merlin Gerin NPJF36120U31AABSCYP
F P500-P630 380-500 V Merlin Gerin NRJF36200U31AABSCYP
Table 3.10 Recommended Circuit Breakers
3.4.13 F-Frame Mains Contactors
Frame size Power & Voltage Type
F P450-P500 380-500 V Eaton XTCE650N22A
F P560-P630 380-500 V Eaton XTCEC14P22B
Table 3.11 Recommended Contactors
3.4.14 Motor Insulation
For motor cable lengths ≤ the maximum cable length, the
motor insulation ratings listed in Table 3.12 are
recommended. The peak voltage can be twice the DC-link
voltage or 2.8 times mains voltage, due to transmission
line effects in the motor cable. If a motor has lower
insulation rating, use a dU/dt or sine wave filter.
Nominal Mains Voltage Motor Insulation
U
N
≤ 420 V
Standard U
LL
= 1,300 V
420 V < U
N
≤ 500 V Reinforced U
LL
= 1,600 V
Table 3.12 Recommended Motor Insulation Ratings
3.4.15
Motor Bearing Currents
Motors with a rating 110 kW or higher combined with
frequency converters are best with NDE (Non-Drive End)
insulated bearings to eliminate circulating bearing currents
caused by motor size. To minimise DE (Drive End) bearing
and shaft currents, proper grounding is required for:
•
Frequency converter
•
Motor
•
Motor-driven machine
•
Motor to the driven machine
Although failure due to bearing currents is infrequent, use
the following strategies to reduce the likelihood:
•
Use an insulated bearing
•
Apply rigorous installation procedures
•
Ensure that the motor and load motor are
aligned
•
Strictly follow the EMC Installation guideline
•
Reinforce the PE so the high frequency
impedance is lower in the PE than the input
power leads
•
Provide a good high frequency connection
between the motor and the frequency converter
•
Ensure that the impedance from frequency
converter to building ground is lower than the
grounding impedance of the machine. Make a
direct ground connection between the motor and
load motor.
•
Apply conductive lubrication
•
Try to ensure that the line voltage is balanced to
ground.
•
Use an insulated bearing as recommended by the
motor manufacturer (note: Motors from reputable
manufacturers typically have insulated bearings
as standard in motors of this size)
Installation Operating Instructions
MG37A202 Danfoss A/S © Rev. 2014-07-29 All rights reserved. 29
3 3
To Next Page
Loading...
Need help?
General
