Use Of Aluminum Conductors - Siemens 1LA8 Operating Instructions Manual

Electrical connection
6.4 Connection
to use wire end ferrules, then before connecting the cable, attach these so as to form an
appropriate, current-carrying crimped joint at the end of the conductor.
Danger of explosion if the conductor ends become too hot
If the end of the conductor is not correctly enclosed by the wire end ferrule, but is trapped by
it, this can lead to overheating. The temperature class of the machine can be exceeded. This
can trigger ignition of an explosive mixture. This can result in death, serious injury or material
damage.
● Insert only one conductor end into each wire end ferrule. Attach the wire end ferrule
● Insert only one conductor end into each terminal.
6.4.5

Use of aluminum conductors

If you are using aluminum conductors, comply in addition with the following:
● Use only cable lugs that are suitable for connecting aluminum conductors.
● Immediately before inserting the aluminum conductor, remove the oxide layer from the
● Then grease the contact areas immediately using neutral vaseline in order to avoid re-
74
WARNING
correctly.
contact areas on the conductor and/or the mating piece, by brushing or filing.
oxidation.
NOTICE
Aluminum flow due to contact pressure
Aluminum flows following installation due to the contact pressure. The connection with
the clamping nuts can loosen as a result. The contact resistance would increase and the
current-carrying impeded; as a consequence the terminal box and the surrounding
components could burn. This could result in material damage to the machine or even in
total failure, which could in turn lead to indirect material damage to the system.
Retighten the clamping nuts after approximately 24 hours and then again after
approximately four weeks. Make sure that the terminals are de-energized before you
tighten the nuts.
SIMOTICS TN Series N-compact 1LA8
Operating Instructions 05/2014