Additional Grounding Requirements - Ul (Nec); Selecting The Control Cables; Shielding; Signals In Separate Cables - ABB ACH580-01 Hardware Manual

102 Guidelines for planning the electrical installation
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.
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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

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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.
A double-shielded cable (a) is the best alternative for low-voltage digital signals, but
single-shielded (b) twisted pair cable is also acceptable.
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Signals in separate cables

Run analog and digital signals in separate, shielded cables. Do not mix 24 V DC and
115/230 V AC signals in the same cable.
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Signals that can be run in the same cable

If their voltage does not exceed 48 V, relay-controlled signals can be run in the same
cables as digital input signals. The relay-controlled signals should be run as twisted
pairs.
a b