PFISTERER Connex | Separable Connectors Specification Guide for Medium Voltage Electrical Systems

Published 23 Jul 2021

PFISTERER Connex | Stocked & Distributed in the UK by Thorne & Derrick

The following guide is designed to help with the specification of PFISTERER CONNEX Separable Connectors size 0 – 3/3-S. You can access the form using the link below.

Specification Form 

PFISTERER Connex Separable Connectors

Thorne & Derrick provide competitive prices and fast delivery from stock for the complete range of LV MV HV Power Products manufactured by Pfisterer – this includes Pfisterer CONNEX MV HV cable plugs and terminations.

The application, cable and MV-CONNEX Separable Connector need to be matched.

Only adapted connectors can achieve the required reliability in the grid.

For cables according to DIN VDE standard, a simplified selection process is possible.

See the beginning of “Section B”.

For cables that have not been produced to comply with DIN VDE, a product configurator is used to determine an individual article number for the required MV-CONNEX Separable Connectors size 0-3/3-S. In order to be able to define the article number, the Specification Form for MV-CONNEX Separable Connectors must be completely filled-in by the project specialists of the customer.

The individual article number consists of a 9-digit number plus an optional variant code. This article number contains all parts for connecting and earthing the individual cable. This article number is marked as Set – which means 3 pieces of the same connector.

Please find instructions below, which will help to correctly fill in the CONNEX Specification form.

The parameters needed can be separated into two groups:

A. Application specific parameters

B. Cable specific parameters

Please complete section ‘A’ and ‘B’.

Section A: Application specific parameters

GIS/Trafo Socket

The cable connector and the socket have to be the same size. The electrical parameters and dimensional measures are defined in the standards EN 50180 and EN 50181.

The following details might help you:

• size 0: lᴺ=250A;  Uᵐ=24kV
• size 1: lᴺ=630A;  Uᵐ=36kV
• size 2: lᴺ=800A;  Uᵐ=42kV
• size 3: lᴺ=1250A;  Uᵐ=42kV
• size 3-S: lᴺ=1250A;  Uᵐ=52kV

It is important to know the size of the socket of which is installed in the switchgear or the transformer.

Application

Depending on the application some special materials and/or additional components are needed.

For application “offshore” or for application “soil-resistant”, special material for housing and sealing is provided.

The section”offshore” should also be ticked if the application is in a coastal area where there is a saline/corrosive atmosphere. Soil-resistant is used if the cable connector itself is underground.

Lowest Ambient Temperature

The standard ambient temperature range is from +50ºC down to -25ºC. For applications where the ambient temperature goes down to -45ºC a special low temperature grease is needed. The temperature directly around the Separable Cable Connector is relevant.

Please note that for indoor application the decisive factor is the ambient temperature inside the building.

Connector Plug-in Location

Only for single sockets installed from inside of the equipment (not relevant for transformer elbow bushing or cast resin joints).

If the application is “outdor” and if the socket entry is from the top, an additional sealing system has to be applied. This is needed to prevent rain/water from entering the connector.

Therefore, please indicate if the position of installation is “top entry” or “other” (not top entry).

Voltage Tap

The voltage tap serves as an interface for a continuous voltage indicator system (DSA-LRM, DSA-2, DSA-i3). This is used to ensure the absence of voltage in the cable system before working on the cable system. For the indication of voltage, a separate product is needed (not in the scope of supply of the connector). To connect this voltage indicator system, the voltage tap (additional components) has to be included in the connector kit. Please indicate “yes” if needed.

standard is “no”

Section B: Cable specific parameters

For cables according to DIN VDE standard, a simplified process is possible. To select the connector, only “cable type”, “cross section”, “voltage level” and “section A” are required.

The simplified process is valid for the following cable types:

In case of non-DIN VE cables, please indicate all the cable parameters.

Cable Design

Single core cable or three core cable.

A three core cable only has to be indicated if the accessories for cable break out have to be included in the cable kit. If those accessories are not needed as they are e.g. already supplied in scope of project, single core cable can be selected (please indicate cable screen and armouring only for the single core cable).

Voltage Level

Voltage level of the cable

U⁰ = phase to earth voltage

Uⁿ = nominal voltage; phase to phase voltage

Uᵐ  max. operating voltage (2 x U⁰)

Common voltage levels as reference:

Conductor Cross Section

Cross Section is only a reference value and does not influence component selection.

Conductor Diameter & Type

The contact system consists of several components. The components are selected according to the conductor type and the diameter of the conductor. The diameter of the bare conductor is relevant (without semi-con conductor screen).

The components have a designed working tolerance in which the can be used. During cable preparation and connector assembly, the conductor diameter has to be within this tolerance, for the contact system components to fit properly.

Conductor types (IEC 60228):

RM: stranded circular (class 2)

SM: stranded sector

RE: solid circular (class 1)

SE: solid sector

RF: super-flexible stranded (class 5+6)

The standard is RM stranded circular (class 2).

Insulation Diameter

The insulation diameter defines the correct insulating part of the connector. The diameter of the bare insulation (without semi-con insulation screen) is required.

The insulating parts have a designed working tolerance in which they can be used. During cable preparation and connector assembly the insulation diameter has to be within this tolerance, for the insulating part to fit properly.

Semi-Conductive Insulation Screen

Depending on the semi-conductive screen type and layer thickness, a special assembly method with special components is used.

• Fully Bonded: The semi-con insulation screen is removed with a cable peeling tool. Standard for DIN VDE cables. Standard thickness is ≤ 1mm; in case thickness is ≥ 1mm please indicate the thickness of semi-con layer.
• Easy Strip: The semi-conductive insulation screen can be removed without a cable peeling tool.
• Graphite: The cable has a layer of graphite on the insulation. This could be the case with older cables, but is not common with new cables.
• Without Semi-conductive Layer: if a low voltage cable or a medium voltage cable with only 2 kV voltage level is used the insulation could be without semi-con insulation screen.

The standard is fully bonded, thickness ≤ 1mm.

Cable Screen

Depending on the cable deign the cable core could have one or more metallic layers. If these metallic layers are indicated on the specification form (Cable screen, 1st and 2nd armoring) corresponding accessories to connect and to ground these layers are supplied.

Diameter values are over each metallic layer.

The standard is: cable screen = Cu wire screen, without 1st and without 2nd armouring.

• Wire: made from Cu or Al
• Laminated foil ( ≤ 0,1 mm): made from Cu or Al
• Tape: made from Cu or Al
• Lead Sheath: made from Pb
• Corrugated Sheath: made from Cu or Al
• Wire Mesh: made from Cu

If your cable had another special cable screen, please indicate this on the form, e.g. fibre optics or up to 3 separate earthing leads (3 core cables).

Outer Cable Jacket

Diameter of the complete cable. For cables with very big or very small diameters, a special assembly method with special components is applied.

PFISTERER

The Pfisterer corporate group has been dealing with the interfaces in the flow of electricity ever since it was founded back in 1921.

As a specialist in energy transmission and distribution, Pfisterer offer our customers and business partners a range of sophisticated, future-ready products: For all voltage ranges and wherever reliable, long-lasting systems are needed for powerful energy grids.

As well as the energy sector, they are also active in transport technology and industrial solutions.

Key Product Categories: Duct Seals | Cable Cleats | Cable Glands | Electrical Safety | Arc Flash Protection | Cable Jointing Tools | Cable Pulling | Earthing | Feeder Pillars | Cable Joints LV | Joints & Terminations MV 

Further Reading

• PFISTERER CONNEX Selection Design Guide for Standard & Variant Inner Cone Plug Connectors Size: 306.50 KB