Siemens SIMOTICS FD 1MM1 Series, Operating And Installation Instructions

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6.6 Connecting the auxiliary circuits
6.6.1 Selecting cables
Take the following criteria into account when selecting the connecting cables for the auxiliary
circuits:
● Rated current
● Rated voltage
● System-dependent conditions, such as ambient temperature, routing type, cable cross-
section as defined by required length of cable, etc.
● Requirements according to IEC/EN 60204‑1
● Requirements according to IEC/EN 60079‑14
Use only sealing plugs, cable entries & conductor entries and thread adapters that are certified
and marked for use in the respective hazardous zone.
6.6.2 Bringing cables into the auxiliary terminal box and routing them
The required data for connecting the auxiliary circuits is located on the terminal diagram on the
inside of the respective auxiliary terminal or terminal box cover.
● In some cases a terminal strip is installed in the main terminal box for the auxiliary circuit
connections.
● The required stripped length on conductors for auxiliary terminals differs according to
terminal type (6 to 9 mm). When the length is correct, the conductor should reach the stop
in the terminal and at the same time the conductor insulation should reach the contact part
of the terminal.
Adapting the cable glands
A plate is bolted to the terminal box enclosure via a rectangular cutout through which the
connecting cables enter. The plate is generally delivered with threaded holes and cable glands.
1. Open the auxiliary terminal box and undo the cable entry plate screws. Depending on the
terminal box version, the cable entry plate is below a steel screening plate.
2. For the undrilled version, drill the required number of holes or threads in the required size
of the cable gland into the cable entry plate.
3. Mark the cables if necessary for subsequent assignment.
4. Pull the cables through the cable glands and the cable entry plate, and connect the cables.
5. Fit the cable entry plate.
6. Make sure that the seal on the screwed sockets for the cable glands satisfies the degree of
protection.
Electrical connection
6.6 Connecting the auxiliary circuits
SIMOTICS FD 1MM1
Operating Instructions 02/2019
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