The compact designed cast resin Busbar ISOBUS TKL is intended for use in both AC and DC circuits.
For AC circuits the voltage range is up to 24 kV and rated current is up to 12,000 A, frequency can be 50 or 60 Hz.
For DC circuits the voltage range is up to 33 kV, rated current up to 18,000 A.


Cast-resin Busbar ISOBUS TKL is manufactured for low and medium voltage systems.

Low voltage systems:
Nominal voltage Up to 1 kV Up to 1,5 kV
Nominal current Up to 6 100 А Up to 10 000 А


Medium voltage systems:
Nominal voltage Up to 24 kV Up to 33 kV
Nominal current Up to 12 000 А Up to 18 000 А


  • ISOBUS TKL is intended for operation in ambient temperatures ranging from -60° to +55 °C
  • The lifespan of the product is over 50 years
  • With degree of protection up to IP68, it’s an optimal solution for marine, offshore & wet environments
  • The very high fire rating greater than 3 hours, means that it is perfect for service entrance and risers in civil construction
  • ISOBUS TKL has extreme resistance to chemicals & aggressive atmospheres
  • ISOBUS TKL can be easily modified and extended as the application grows/needs change
  • Suitable for outdoor & indoor application
  • Maintenance free
  • High degree of fire rating
  • No phase to phase short circuit possible
  • Partial discharge free according to IEC 60137
  • Natural (air) cooling
  • Very low power losses (I²R)
  • Lowest lifecycle costs for end clients

E-Cu or E-Al conductors are embedded in a cast resin & inert fine particle, composite insulation material. The compound has excellent dielectric properties together with high mechanical strength. It is also extremely resistant to corrosive atmospheres.
We use universal casting forms that incorporate simultaneous automated monitoring; this means we can produce an almost unlimited number of different shaped elements. We can produce both standard and custom built solutions. Elements have an overall maximum length of up to 6 meters (20 feet).
The shaped elements are manufactured in various configurations: L-shaped, T-shaped, with bends from 90° to 170°, T-offs, elements with a double bend, custom elements, etc.

ISOBUS TKLN — Low voltage systems: Copper or aluminum conductors (from 2 to 10), sealed in one housing made of a special compound. In the same housing a neutral and/ or a protective conductor (section of 50%, 100%, and 150%) can be placed. Busbars are completed with holders for the busbar support during the installation on metal structures. Special assembly supports are provided.

ISOBUS TKLC — Medium voltage systems: The air gaps are designed in to allow for natural cooling of the busbar. Single or paired conductors can be used in the busbar design. Busbars are completed with a self-supporting screen, and holders for the busbar support during the installation on metal structures. Special assembly supports are also provided.

Medium voltage systems are completed with a special mesh protective screen. Busbars for outdoor installation are completed with a climate screen.

TKLC with mesh protective screen for indoor application

TKLC with climat screen for outdoor application

Examples of elements
ISOBUS TKL elements are made of self-extinguishing materials. They have a very high fire rating. The corresponding test reports and fire certificates are issued for them. Wall penetrations are fire safe. Openings, through which a busbar runs, are filled with special noncombustible materials.

Low voltage examples ISOBUS TKLN:

Straight element

Welded elbow element

Double elbow element

Welded element

Terminal element

Medium voltage examples ISOBUS TKLC:

Straight element

Welded elbow element

Double elbow element

Bend T-element

Terminal element

Cast-resin busbar ISOBUS TKL can be installed in the following variations: ceiling, floor, wall, both horizontal & vertical.

The busbar ISOBUS TKL consists of separate elements. Electrical connections elements sections are carried out by means of copper or aluminum plates which have embedded nuts. These are tightened by using stainless steel bolts with the correct torque applied, as defined in the installation manual. After the assembly, the bolted connections are cast with the same compound with which the insulation material of the busbar’s elements is made, thereby providing the insulation continuity through the whole length of the route.


  1. Aluminum profile (for mounting of the busbar and for the screen installation)
  2. Aluminum or copper conductor
  3. Cast connection
  4. ISOBUS TKLC busbar element
  5. Bolted connection
  6. Air gaps for natural cooling


  1. ISOBUS TKLN busbar element
  2. Copper/Aluminum connection plate
  3. Spacer between phases
  4. Pressure plate
  5. Bolt

Electric Connection Methods
Due to the almost endless variety of the busbar element’s shapes they can connect to any form of electric equipment (from the top, from a side, from the bottom):

Protective boxes may be used for protection of contact connections (degree of protection IP65)

Press-welded flexibles

High-flexible braids

To compensate the linear changes caused by the temperature differentials, the special expansion element is installed through each 20-25m of a direct route.

UL and IEEE Certifications are in process.

In addition to in house routine testing our products have undergone rigorous type testing as follows:

  • Heat tests;
  • Tests for stability under continuous currents of a short-circuit;
  • Tests for resistance to mechanical factors of the environment;
  • Tests for mechanical stability;
  • Water-proof and dust-proof tests;
  • Tests for heat resistance and frost resistance during the operation, transportation and storage;
  • Tests of the electric strength of insulation;
  • Test for the intensity of partial discharges;
  • Seismic stability tests and other tests.

The delivery includes:

  • Cast-resin busbar type ISOBUS TKL elements;
  • Connection plates;
  • Molds for casting the elements‘ joints during the installation;
  • Fixation system;
  • Chemical components for compound preparation (during the installation);
  • Flexible connectors;
  • Grounding cables;
  • Factory packaging (wooden pallets/boxes).

If applicable additional material is supplied as well, like:

  • A vacuum mixer with the drive (for medium voltage);
  • Protective boxes;
  • Accessories


The content of the documentation is as follows:

  • Packing list;
  • The set of assembly factory drawings;
  • Installation instruction manual;
  • Test reports for each element;
  • Technical passport.


Depending on the specification requirements, cast resin busbar ISOBUS TKL can be connected to almost any additional electric equipment:

  • Current transformers
  • Voltage transformers
  • Disconnecting switches
  • Tap off boxes with MCCB
  • Terminal elements for the cable connection
  • Overvoltage limiters
  • Automatic circuit breakers
  • Tap-offs for other rated currents


According to the design documentation busbars & components are packed and fastened into wooden boxes. Separately delivered small size assembly units, details and fasteners are packed into wooden boxes according to the design documentation.