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SD1too · 26th October 2019, 17:57

Hi Steve,

Thanks very much for the two boards. Royal Mail excelled themselves, the package arrived this afternoon around 4 pm.

A close examination has revealed that two brushes are wired to the red wire which is the positive supply. Both are therefore in circuit when the slow speed relay is triggered at 104 degrees. The earth return is via the single brush connected to the black wire.

This arrangement means that this single brush carries twice as much current as each brush connected to the positive supply. We would therefore expect the single brush connected to the black wire to wear at twice the rate of the other two and that is exactly what appears to have happened.

Thanks for this Steve.

Simon

26th October 2019, 17:57	#12
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,344 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	3 wire 2 speed motor for 1.8 engine Hi Steve, Thanks very much for the two boards. Royal Mail excelled themselves, the package arrived this afternoon around 4 pm. A close examination has revealed that two brushes are wired to the red wire which is the positive supply. Both are therefore in circuit when the slow speed relay is triggered at 104 degrees. The earth return is via the single brush connected to the black wire. This arrangement means that this single brush carries twice as much current as each brush connected to the positive supply. We would therefore expect the single brush connected to the black wire to wear at twice the rate of the other two and that is exactly what appears to have happened. Thanks for this Steve. Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.