|Handling and Connection of Cables and Lines for Fixed Laying - Course: Basic skills and knowledge of electrical engineering. Trainees' handbook of lessons (Institut für Berufliche Entwicklung, 17 p.)|
|3. Connection of Cables and Lines for Fixed Laying to Electrical Equipment|
Criteria for connections by means of press-sleeves
- Hand pressing plier required.
Figure 20 Pressing plier
1 grips with pawl bolt, 2 setscrew for mechanical end stop
- Applicable for Al and AlCu conductors only.
- Applicable only for three or four conductors with a cross section of 2.5 mm2. (If two conductors are to be connected only, a third or fourth conductor is to be pressed in as filler).
- Shorter assembly time.
- Clamping inserts are not required.
- Longer lasting contact than that of other types of joints.
Sequence of operations
- Conductor length to permit three times re-adjustment. (150 mm are sufficient)
- Strip conductor ends and remove any oxide or other contamination layers.
Figure 21 Branch box prepared for pressing
- Slip press-sleeve over stripped conductor ends with rotary motion. Make sure that all conductor ends contact the bottom of the sleeve!
- Distance between sleeve opening and beginning of conductor insulation should not be more than 3 mm!
- Apply pressing plier at front and compress up to stop.
- Slip insulation sleeve onto pressed sleeve until conical end of insulation sleeve closely fits on press-sleeve.
Figure 22 Finished pressed-joint
1 press-sleeve, 2 insulation sleeve, 3 distance sleeve opening to conductor insulation
Figure 23 Pressed joint in a branch box/conduit box, made and insulated
What are the advantages of pressed joints over clamped