On Sun, 24 Oct 2010 19:18:07 -0500 Dieselhead <126die...@gmail.com> wrote:
> Hey Y'all, > > I am puzzled with a generator problem. For what vehicle? > From the armature terminal a wire goes to the cut-offswitch. Inside > there is a relay. When i push down to make contact, the output > terminal to the armature is energized. I have not seen the relay > engerize by itself Can you get an ohmmeter on the relay's coil's terminals and measure its resistance? > 1. With the engine running: no voltage anywhere in the charging > system except at the battery terminal on the cut-out switch. > > 2. I checked continuity from the Field terminal to the resister, > then through the resistor All good, but I was not able to get from > the resistor to ground. I ran a temp ground from the resistor to the > battery. Started the engine, but still no generating. Is there current flowing through the resistor under this condition? Does the resistor really want to go to ground, or to the battery's positive? > 3. I checked continuity of what internal components of the cut-off > relay that I could. all appeared to be ok. > > > Ran out of daylight. I was not able to check voltage when holding > the relay switch closed AFTER i made sure the resistor had a good > ground. Not enough hands. Get a helper, or tie one lead of the voltmeter to the chassis some way. That way you'll only need two hands. > > IN theory: > > THe battery voltage passes through the relay to the armature. > The field goes through a resister to ground. > > Seems simple. Is this the correct theory? What should I check next? As I mentioned above, the field winding's terminal may want to be connected to the battery positive terminal because the other end of the field winding may be grounded to the case of the generator. > Is there any danger of frying the generator if I hook the battery > directly to the armature for testing at low engine rpm? I don't know for sure. If all the relay does is connect the armature to the battery, no. In that case, why bother changing connections; just push the relay closed. > Seems like that and checking voltage , engine running, with the relay > points closed are the next thing to check. I think checking with the relay points closed is the first thing to check. Craig _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
