ABB ACS480, Руководство по оборудованию, Страница: 73 / 180

￭ Disconnecting the ground-to-phase varistor, or connecting the EMC
filter
Before you proceed, see When to disconnect ground-to-phase varistor, or connect EMC
filter (page 71) . Obey the guidelines.
1. Stop the drive and disconnect it from the power line.
2. Wait 5 minutes to let the intermediate circuit capacitors discharge.
3. To disconnect the varistor, remove the metal VAR screw.
4. To connect the EMC filter, remove the plastic EMC screw, and replace it with the metal
screw included in the drive delivery.
￭ Identifying the earthing system of the electrical power network
WARNING!
Only a qualified electrical professional may do the work instructed in this section.
Depending on the installation site, the work may even be categorized as live
working. Proceed only if you are an electrical professional certified for the work.
Obey the local regulations. If you ignore them, injury or death can occur.
To identify the earthing system, find out the supply transformer connection. If that is not
possible, measure these voltages at the distribution board, and use the table below to define
the earthing system type.
1. input voltage line to line (U
L-L
)
2. input voltage line 1 to ground (U
L1-G
)
3. input voltage line 2 to ground (U
L2-G
)
4. input voltage line 3 to ground (U
L3-G
).
Electrical installation – North America 73
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