Clamps for substations are built in aluminium alloy for pure aluminium, ACSR and aluminiun alloies conductors; while those for copper conductors are built in bronze aluminium.
Screws, nuts and lock washers are in stainless steel.
Bi-metallic combination is made through interposition of an “Elettrocupal” lock washers among pieces of different alloy, in order to avoid the electrolytic couple.
| TIGHTENING TORQUES OF SUBSTATION CLAMPS | |
Stainless steel bolt | Tightening torque [Nm] | |
M8 | 12 | |
M10 | 20 | |
M12 | 30 | |
| RAITED CURRENT OF SUBSTATION CLAMPS | ||
Conductor type | Ø conductor [mm] | Raited current [A] | |
| Aluminium | Copper | ||
| Bare conductor | 5÷12 | 100 | 200 |
| 12÷20 | 250 | 500 | |
| 20÷25 | 400 | 800 | |
| 25÷30 | 500 | 1000 | |
| 30÷36 | 800 | 1600 | |
| 36÷40 | 1000 | 2000 | |
| Stud | 20 | 400 | 800 |
| 30 | 700 | 1400 | |
| 40 | 1200 | 1600 | |
| 50 | 1500 | 2000 | |