Substitute Fuses For; Motor Bearing Currents; Control Cable Routing - GE AF-600 FP Operating Instructions Manual

Electrical Installation
3.1.16 Substitute Fuses for 240 V
Original fuse Manufacturer
KTN Bussmann
FWX Bussmann
KLNR LITTEL FUSE
L50S LITTEL FUSE
A2KR FERRAZ SHAWMUT
A25X FERRAZ SHAWMUT
3.1.17 Motor Insulation
For motor cable lengths ≤ the maximum cable length
listed in the General Specifications tables the following
motor insulation ratings are recommended because the
peak voltage can be up to twice the DC link voltage, 2.8
times the mains voltage, due to transmission line effects in
the motor cable. If a motor has lower insulation rating it
recommended to use a du/dt or sine wave filter.
Nominal Mains Voltage Motor Insulation
≤ 420 V
Standard U
U
N
420V < U ≤ 500 V Reinforced U
N
500V < U ≤ 600 V Reinforced U
N
600V < U ≤ 690 V Reinforced U
N

3.1.18 Motor Bearing Currents

All motors installed with 150 HP or higher power drives
should have NDE (Non-Drive End) insulated bearings
installed to eliminate circulating bearing currents. To
minimize DE (Drive End) bearing and shaft currents proper
grounding of the drive, motor, driven machine, and motor
to the driven machine is required.
Standard Mitigation Strategies:
1. Use an insulated bearing
2. Apply rigorous installation procedures
- Ensure 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 for instance by
screened cable which has a 360°
connection in the motor and the
frequency converter
AF-600 FP High Power Operating Instructions
Substitute fuses
KTS
FWH
KLSR
L50S
A6KR
A50X

3.1.19 Control Cable Routing

= 1300V
LL
= 1600V
LL
Tie down all control wires to the designated control cable
= 1800V
LL
routing as shown in the picture. Remember to connect the
= 2000V
LL
shields in a proper way to ensure optimum electrical
immunity.
Field Installed Network Module options connection
Connections are made to the network options on the
control card. For details see the relevant network
instructions. The cable must be placed in the provided
path inside the frequency converter and tied down
together with other control wires (see illustrations).
Illustration 3.13 Control card wiring path for the 43. Control card
wiring for the 41, 42, 44, 51 and 52 use the same path.
- Make sure that the impedance from
frequency converter to building ground
is lower that the grounding impedance
of the machine. This can be difficult for
pumps
- Make a direct earth connection between
the motor and load motor
3. Lower the IGBT switching frequency
4. Modify the inverter waveform, 60° AVM vs.
SFAVM
5. Install a shaft grounding system or use an
isolating coupling
6. Apply conductive lubrication
7. Use minimum speed settings if possible
8. Try to ensure the line voltage is balanced to
ground. This can be difficult for IT, TT, TN-CS or
Grounded leg systems
9. Use a dU/dt or sinus filter
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