Guys I am trying to get this generator working , it came from a industrial pressure washer with heater, this was suppose to generate energy to power the diesel burner , but i have no juice , there is not much inside , i wonder if is repairable , if it is what is that i need to replace , looks that does not have much stuff inside , but complex enough for a electrical handicap , as I am ,

 

What you have is an Alternator producing AC that is going to a Bridge Rectifier to make DC....




The four terminals on the Square bridge rectifier will be marked with ~ + ~ -, the brushes go to the ~ terminals.

 

If there is a wound set of field coils (As opposed to a permanent magnet field) then the bridge rectifier is probably to provide DC to the field winding. It is also possible that the field is actualy the rotating winding as it is in car alternators. You will need to post a scematic of how it is wired internally so we can see if the output is taken from the fixed winding or from the rotating winding via the slip rings ad brushes. We also need to know hoe the thing that looks like a capacitor is connected.

Les.

 

i work on generators, guessing from what you show. it is a simple set up..
the generator is a AC OUTPUT hence the outlets. the bridge rectifier (the square block) provides dc voltage to the armature to create the magnetic field to generate power. the capacitor is most likely a filter.
also the armature may have lost it's residual magnetism, in that case you would have to FLASH it.. to flash it, you would reassemble the generator.
get a old lamp cord plug it into the generator, and then connect it to a 12v battery for just a second. this should give it residual magnetism, so that it can then self excite again..if generators sit for years unused, they can loose their mojo..
i'd check for continuity at the outlet, and check for continuity on the slip rings ( armature) and then check all points to ground to make sure there is no shorts.. the bridge rectifier may be all that is wrong.. that's about all i can tell you for now..
good luck.. keep us posted..

 

also the armature may have lost it's residual magnetism

I've never done it myself but the local small engine repair guy claims that small AC generators can be flashed by turning the shaft backwards for 10 to 20 seconds (he uses an electric drill with some type of adapter). I was surprised that would do it. Have you ever done that, @dacflyer ?

 

Maybe let it run for a while to see if it comes back to life, if you haven't already.

I have an old 1960's or 70's 2kW generator that has this issue. Every few years I'll fire it up and sometimes there is zero output. But after it runs for a few minutes it will come back to life. It's obvious the instant it happens because the load on the motor suddenly increases, even if there's nothing plugged into it. So either the magnetism is on the edge and increases just enough when it gets warm, or maybe the brushes are just dirty and have to run for a few to get scrubbed clean... but once it's working, it's working..until it sits for a few more years.

 

I've never done it myself but the local small engine repair guy claims that small AC generators can be flashed by turning the shaft backwards for 10 to 20 seconds (he uses an electric drill with some type of adapter). I was surprised that would do it. Have you ever done that, @dacflyer ?

that has never worked for me,, and it is not good for the engine either...