The classic phase clamp for rectangular-section conductors is a screw-fastening clamp allowing the tightening of conductor between the clamp’s body and its mobile jaw. The tightening force is provided by the clamping torque of the clamp’s driving screw. Both the clamp body and the jaw are aluminium alloy die cast items. The driving screw has a ‘’RO bayonet’’ end which allows easy coupling and detachment of the clamp from the ‘’RO bayonet’’ coupling systems of insulating sticks.
The dismounting of the clamp from the conductor is obtained through mobile jaw’s lowering, followed by the detachment of the clamp from the conductor.
The automatic phase clamp for rectangular-section conductors is also a screw-operated fastening clamp, the conductor being tightened between the clamp’s body and its mobile jaw. Additionally, this type of clamp is provided with a system of levers and springs that allows the automatic closing of the clamp’s jaw upon the contact of levers with the conductor (pre-fastening of the clamp on the conductor). Subsequently to this phase, which provides much easier handling the clamp, the fixing of the clamp must be completed through the tightening of the driving screw to the proper torque specification. Similar to the classic clamp, the automatic clamp includes two aluminium alloy cast items and a driving screw provided with a ‘’RO bayonet’’ end.
The dismounting of the clamp from the conductor is similar to the one used by the classic clamp, more exactly the screw is unscrewed , the jaw is lowered until there is sufficient space to detach the clamp from the flat bar.
|Technical characteristics||Classic clamp (C)||Atomatic clamp (CA)|
|Nominal short-circuit for t = 1 s Isc (kA)||30||30|
|Clamp body execution procedure||Cast body||Cast body|
|Material||Aluminium alloy||Aluminium alloy|
|Thickness of conductor bar where the phase clamp can be applied (mm)||40||37|
There are two types of phase clamp for rectangular-section conductors: flat bars, bar packets or flat iron of various thicknesses: