Posted by Sherman in Idaho [24.32.202.166] on Thursday, April 18, 2013 at 03:16:53 :
In Reply to: polarizing 6 volt system posted by mark from mass [98.217.11.91] on Wednesday, April 17, 2013 at 20:59:23 :
"Polarizing" is also called "flashing the field". You basically just get a piece of wire long enough to touch one end to the ungrounded battery post (+ or - as the case may be) and touch the other end to the field terminal of of the generator momentarily with the engine running.
If you're changing the polarity of your system, or if the generator hasn't been used for a very long time, the flashing serves to set up some residual magnetism in the iron which will be enough to get it to start making electricity. It has to make a little bit of electricity even with no field current in order to produce enough to get the regulator to start feeding current into the field winding, at which point it quickly builds up the field to full strength.
I would suggest first just run the engine at 1000 rpm or so and see if the ammeter indicates charging and if the voltage on the battery is greater than 6.3V. If so, it already has enough magnetism in the field iron and you don't have to flash it.