VARIAC transformer round shape brush VS Flat carbon brush

[Kiriakos GR]

Supposedly round shape carbon brush this has significantly longer life cycle than regular shape of carbon brush.

This is a claim made by Carroll & Meynell in UK, they present their brand as transformer manufacturer, and within 2016 they awarded their engineer with Indian origin about this new design.


Unfortunately for any brand which trying re invents the wheel, their problem is that the world this is full of wheels.

My own research at finding a new or used (made in Europe VARIAC), this helped me to discover that round shape brush in VARIAC transformers’, this is a Made in Germany (engineering – idea).

Thanks to eBay German sellers, lots of museum class equipment is available in their auctions.

Brand named as: Gebr Ruhstrat Lenglern, this is from first ones which they use round shape brush in their VARIAC at 70’s or so.
Over the years this company it is alive by the branding Ruhstrat Transformers & Resistors.

Another brand using also this round shape brush this is Schuntermann Transformers GmbH.

While, The chicken or the egg causality dilemma this is hard to solve, about the dilemma of whom did use first, these round shape brush, or better described as wheel shape carbon brush, this is much easier to solve. 

I wrote this topic so other people with similar level of curiosity, them to be helped too.