3.1.2.2 Connections of the Current Terminals
Fixing Elements
The fixing elements for the transformer connection are part of the current terminal (housing side). They have a
stress-crack- and corrosion-resistant alloy. The head shape of the terminal screw allows for using a flat screw-
driver (5.0 x 1.0 mm) or a crosstip screwdriver (PZ2). We recommend PZ2.
Cable Lugs and Wire Cross-sections
There are two connection options: the connection of single wires and the connection with a ring lug. Only
copper wires may be used.
We recommend ring lugs with the following dimensions:
Figure 3-5
For complying with the required insulation clearances, insulated ring lugs have to be used. Otherwise, the crimp
zone has to be insulated with corresponding means (e.g. by pulling a shrink-on sleeve over).
We recommend ring lugs of the PIDG range from Tyco Electronics.
Two ring lugs can be mounted per connection.
Figure 3-6
As single wires, solid conductors as well as stranded conductors with conductor sleeves can be used. Up to
two single wires with identical cross-sections can be used per connection.
SIPROTEC, 7SK80, Manual
E50417-G1140-C344-A5, Release date 11.2012
Ring lug
Current transformer connection
Mounting and Commissioning
3.1 Mounting and Connections
309