Posted on 15 May 2020

Connection Systems - Connectors and Terminals








Below is a description of the benefits and field of application for several electrical connection systems.


Clamping Yoke Screw Connection

The clamping-yoke connection is the most used screw connection in the world. Steel clamping yokes made by using a stamping and bending process guarantee a vibration proof clamp connection. When the screw on the clamp is tightened, there is a counter effect in the clamping yoke's threaded area which prevents the connection from accidentally loosening. As the screw thread is on an inclined plane, there is a force gain created and a very high clamping force is achieved. Hardened steel with optimal corrosion protection can be used for stability and security, and copper alloys in the contact area for good electrical conductivity.



  • The screw connection guarantees a globally accepted, vibration proof, and maintenance free connection.
  • A large conductor clamping area is covered.
  • The "Wire Ready" technology ensures that the terminal points are fully open at delivery, even after being transported world-wide
  • The "Wire Guard" protection mechanism prevents accidental insertion of the wire underneath the clamping area, which can be dangerous, and it protects against hidden faulty contacts
  • The flat clamping yoke also enables the clamping of very small cross-section wires

Field of Application

The standard connection for applications in industrial environments with the highest requirements for reliability even under harsh conditions.


PUSH IN Spring Connection

The PUSH IN spring connection with direct plug-in technology allows the fastest wiring process: the stripped or prepared wire is simply pushed into the terminal point as far as it will go and the connection is finished. Operating the release lever is only required with very standard wire or to release the connection. The stainless steel spring ensures a high contact force between wire and the tinned copper busbar. A stainless steel cage enclosure prevents subsidence in the contact area. To prevent any drop in clamping force, plastic parts are deliberately not used.



  • Fast, toolless wire connection with direct insertion technology
  • The stainless steel spring results in a vibration resistant connection
  • Higher resistance to wire pull-out than in a tension clamp system
  • Constant conductor clamping force independent of the operator
  • Operator error is reduced using a color coded and intuitive actuator
  • Wire feed and the operation are aligned in the same direction which permits a compact equipment design

Field of Application

The default choice for operation in the field, it permits speedy wiring and, combined with its small size, its intuitive use is also advantageous even in environments with severe vibration.


 TOP Screw Connection Terminal with Pull-Effect

In the traditional case, the screw is always at a right angle to the conductor outlet direction, the TOP connection however, allows wire insertion and the screw orientation in the same direction. The TOP connection produces the greatest possible packing density in the terminal area. The ”pull effect“ ensures that the connected wire is pulled in to the clamping point, producing a secure contact.




  • The “pull effect” pulls the wire into the terminal point. Problems with clearance and creepage distances are avoided.
  • Wire feed and the operation are aligned in the same direction, which permits a compact equipment design
  • The minimum installation height results in an extremely high packing density

Field of Application

Housing design or installation requirements such as PCB slots, that do not allow a right angled screw operation for reasons of space.


Tension Clamp Connection

The pre-tensioned tension clamp made from high quality rust and acid resistant steel pulls the wire against the galvanised copper busbar, resulting in a permanent and vibration resistant connection. The spring can be opened with a screwdriver. The wire is fed through the wire guide into the spring cage. When the screwdriver is removed, the wire is clamped. The surface-treated busbar ensures low contact resistance and a high resistance to corrosion.



  • Constant conductor clamping force independent of the operator
  • Widespread connection technology
  • Simple operation using a screwdriver or the integrated release lever

Field of Application

Fast wiring with a constant clamping force, even in environments with severe vibration.


Crimp Connection

The crimp connection method provides an affordable solution with pre-assembled female plugs that is also  appropriate for large batch jobs. The crimp contacts can be attached using hand tools or with a crimping machine when producing large batches. The contacts then only need to be locked into the housing provided. For fully  automated processing, taped crimp contacts are available.




  • Rapid, fully automated preassembly of connectors is possible
  • Long lasting, positive connection methods
  • Minimal contact resistances
  • The conductor connection is extremely thermal shock and vibration resistant

Field of Application

Applications that combine fully automatic and factory oriented processing steps with the actual field wiring - works even in environments with severe vibration or temperature fluctuations.


IDC Connection (Insulation Displacement Connection)

The IDC connection is the fastest way to install a wire, and is one of the most effective solutions for the end user. In the insulation displacement technique, a cable is pressed into the cutting zone of a fork contact. This cuts the insulation and produces a reliable connection between conductor and the cutting metal. The clamping capacity of different wire crosssections and the choice of insulation material is limited.




  • A particularly easy and time-saving connection method
  • Constant conductor clamping force independent of the operator
  • No special tools needed to connect the wire

Field of Application

All applications where a lot of connections need to be completed in a short period of time and the wire cross-section and insulation material are laid down.


Leaf Spring Screw Connection


The leaf spring screw connection is the oldest method on the market for connecting a conductor. The leaf spring below the screw reliably prevents damage to the conductor when the clamp screw is tightened. The leaf spring is a simplified connection yet suited for the requirements of building automation connection technology.




  • Cost effective alternative to the clamping-yoke connection
  • A particularly simple connection solution suited to less demanding environmental conditions.
  • High power density in a small footprint

Field of Application

Applications with less demanding environmental conditions and narrow installation space.


Flat-Blade Connection


Flat blade connections are a widespread connection method in accordance with DIN 46247. This technology connects preassembled, insulated and noninsulated cable lug sleeves by simply insertion of the cable lug connector on a standard terminal block.




  • Fully automated, preassembled wire bundles are possible
  • Can be used with 2.8 and 6.3mm flat blade receptacles
  • Suitable for insulated and uninsulated versions.

Field of Application

Suitable for applications where pre-assembled cables neeed to be fitted quickly into the PCB.


For more information, please read:

Printed Circuit Boards

Perfect Fit Connectivity Solutions for Drive Controllers and Regulators


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