￭ Additional grounding requirements – IEC
This section gives grounding requirements according to standard IEC/EN 61800-5-1.
Because the normal touch current of the drive is more than 3.5 mA AC or 10 mA DC:
• the minimum size of the protective earth conductor must comply with the local
safety regulations for high protective earth conductor current equipment, and
• you must use one of these connection methods:
1. a fixed connection and:
• a protective earth conductor with a minimum cross-sectional area of
10 mm
2
Cu or 16 mm
2
Al (as an alternative when aluminum cables are
permitted),
or
• a second protective earth conductor of the same cross-sectional area as
the original protective earth conductor,
or
• a device that automatically disconnects the supply if the protective earth
conductor is damaged.
2. a connection with an industrial connector according to IEC 60309 and a
minimum protective earth conductor cross-section of 2.5 mm
2
as part of a
multi-conductor power cable. Sufficient strain relief must be provided.
If the protective earth conductor is routed through a plug and socket, or similar means
of disconnection, it must not be possible to disconnect it unless power is
simultaneously removed.
Note: You can use power cable shields as grounding conductors only when their
conductivity is sufficient.
￭ Additional grounding requirements – UL (NEC)
This section gives grounding requirements according to standard UL 61800-5-1.
The protective earth conductor must be sized as specified in Article 250.122 and table
250.122 of the National Electric Code, ANSI/NFPA 70.
For cord-connected equipment, it must not be possible to disconnect the protective
earth conductor before power is removed.
Selecting the control cables
￭ Shielding
Only use shielded control cables.
Use a double-shielded twisted pair cable for analog signals. ABB recommends this
type of cable also for the pulse encoder signals. Use one individually shielded pair for
each signal. Do not use common return for different analog signals.
Guidelines for planning the electrical installation 87
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