DAU - A Miba Group Company

Multiconnector Bus Bars for Power Electronics

The advanced generation of high power electronics (especially IGBT technique) has generated a high demand on power distribution solutions and thus also on the design engineer of bus bars. Minimal voltage drop, high currents, low inductivity and high capactive coppling between the conductors are some of the critical parameters which are needed for effective Multiconnector Bus Bar systems.

Therefore DAU has developed – together with a major customer – a system of cost effective high performance bus bars – called MBB (Multiconnector Bus Bar) which meet the requirements of any low and mid voltage application (up to 1100 V).

  1. Electrical Advantages:
    Low voltage drop, high noise suppression, low inductivity, high capacitive coppling between the layers, low impedance, high shielding, high current carrying capacity.
  2. Mechanical Advantages:
    High packaging density, low profile design, low weight, high mechanical strengths, modular design, shallow or deep drawn contact surfaces accomodates planar mounting surfaces for IGBT’s or Capacitors, high temperature stability, stable plattform, improved thermal properties due to very good temperature distibution, error free installation.
  3. Economic Advantages:
    Low system costs, low service costs, low installation costs, high quality standard due to high reliability.



Material Data for Mulitconnector Bus Bar Installation Materials:


Description Insulation
Epoxy1013-1016 Ω15-20 KV/mm1804,5
Polyester1018 Ω300 KV/mm6003,5
Polyimide 1014 Ω213 KV/mm3003,8
Polykarbonat1017 Ω35-80 KV/mm4003,0
Teflone1018 Ω40-80 KV/mm6002,1
Mylar/Hostaphan1016-1018 Ω35-60 KV/mm 3253,3

Multiconnector Bus Bars can be manufactored in many sizes and shapes, flat or even three dimensional, with up to 5 layers of conductors. The size and finish of the conductors, the type and number of terminals - threaded inserts, connector blocks, quick connectors or shallow or deep drawn contact surfaces as well as different types of dielectric materials can be designed specificly to be demand of the costumer. Creepage clearances between conductive surfaces can be increased with valleys or walls to meet the necessary requirements.

Multiconnector Bus Bars provide an easy design for structured power distribution compared to error prone wire harness. Rectangular conductors also offer a higher current carrying capacity than round wires. Due to the low inductance Bus Bars are preferable for connections between Insulated Gate Bipolar Transistor (IGBT) moduls and DC capacitor banks.

Finished assemblies - glued together with special glue - are verified dimensionally and mounted together precisely. The accurate terminations and overlays provide an error free customer assembly where active and passive components can be integrated to a complete power distibution subsystem.

DAU Multiconnector Bus Bars consists of several layers of conductors insulated by thin layers of Polycarbonate or other special insulation materials (depending on the application). Pure copper - tin plated - is the most widely used bus bar material. Aluminium is used when weight is a factor but its conductivity is only 60% that of copper. Other materials which can be used are brass and beryllium copper.


Material data for Bus Bar Conductor Materials:


Description Electrical Conductance
Specific Weight
Kupfer (Ecu F30)568,95
Messing158,1 - 8,7
Be-Bronze22 - 308,26


Multiconnector Bus Bar systems offer elegant solutions for manufactors of sophisticated electronic equipment. MBB‘s are manufactored by DAU with CNC programmed cutting and punching machines. Tin plating protects the copper from corrosion and provides reliable electrical connections. The dielectric films used for insulation provide high dielectric strength and can be chosen to tailor the capacitance and impedance. Multiple conductors and connectors can be housed into the assembly.

Finished assemblies are verified dimensionally and electrically to the customer’s request. Design is always optimized for  compact, efficient current distribution. Nearly unlimited package sizes are possible.

Current distribution in modern power supplies and digital systems request the design engineer to eleminate bulky wires. Well designed Bus Bars can reduce significant space and installation time.

made of Aluminium

or Copper welded together with the insulation material to a uniform package

threaded inserts