… delays the happy moment I’m working for since quite a while.

Since quite a while my main work and my main brain occupation revolves around the genset.

All is assembled and connected except of the right part of the genset enclosure which I keep open to be able to see if all hoses are tight when there is pressure inside.

My final main concern was the polarity of the brushes of the generator. The field is flashed by a DC current to enable an easier start of the genset. But a DC current creates a magnetic field of certain direction. With a wrong polarity the field points in the opposite direction and the generator might not start up or can get damaged. The manual says the red cable on the F+ connector and the black one on the other connector. But, there’s always a but, both cables are white. But, there is another but, a technician working on the brushes marked one cable with little piece of cable tie. Is this the for the F+ or F- connector?

I decided it’s for the F+ connector. But, there is a third but, is my decision correct or wrong?

Paul, the electrician says polarity is not important. The same was said by Harry, one of his electrical engineers, says the same. Because of the field direction of a DC current, me, the physicist is convinced that polarity matters. Who is right??? 2:1!

I don’t recall how often I read through the manuals. As they are digital editions I searched yesterday by accident for “flash” and found a small paragraph titled “Testing Field Flash”. Don’t know why I never came across this little paragraph before. (Seems I need glasses, stronger ones…)

And in this paragraph I saw how I can make the test. A test to see if my decision about the polarity is correct or if I need to work for 1 – 2 h to change the polarity.

I cranked the genset (with the governor unplugged to prevent the diesel engine to start) and happy moment No. 1 of the day! My polarity decision is correct!

As I built in new fuel hose there is the fuel line to each cylinder. The first cylinder was bled quickly. Happy moment No. 2 of the day.

On my way to happy moment No 3 and 4. the battery got flat. Since weeks it was not charged and had just enough power to start the PRT Volvo. My Volvos start extremely fast. But the genset needs priming, field flashing, and the generator turns during cranking this requires quite some power.

Now I’m charging the PRT engine battery and have to be patient until tomorrow morning when the battery is full and I can go for my happy moments No. 3 and 4.