st generator head

[berrybus]

 i have a st generator that has set for 2 yrs. it wont put out any power. i read something about recharging the thing with a 12 volt battrie but cant seam to get it to work. any sugestions?thanks thanks jim.

[Sean]

A little more information will help.  Is "ST" the brand?  What model is it? Rating and other specs?

Also, is the motor running and the head spinning, just not making power?  Where are you measuring the voltage?

If the generator was working fine before it sat for two years, "flashing the field" is not the most likely issue, which is what I think you are referring to when you say "recharging."

-Sean
http://OurOdyssey.BlogSpot.com

[berrybus]

this is a china made generator head. its a 15kw direct drive. i cant get any voltage reading on any wiring . i have tried to figure out how to flash the thing but every thing i read dosent give enough information on how to do it in detail. its strange how it worked before.thanks jim.

[Lin]

Does it have a reset button or fuse somewhere?

[Sean]

this is a china made generator head. its a 15kw direct drive. i cant get any voltage reading on any wiring . i have tried to figure out how to flash the thing but every thing i read dosent give enough information on how to do it in detail. its strange how it worked before.

Again, if you are getting no reading at all on a generator that was previously working, it is unlikely to be a residual magnetism issue.  Much more likely to be an open circuit someplace.

Without a make, model, or wiring diagram, it will be next to impossible for anyone to help you by typing on a bulletin board.  There are too many unknowns (regulation, field excitation, stator wiring, etc. etc.).

It could be as simple as a blown fuse, or maybe a bad transistor in the regulator (if any).

As much information as you can provide here will make things easier.  Photos, markings, wiring diagrams, anything.

-Sean
http://OurOdyssey.BlogSpot.com

[robertglines1]

I have seen these on E-Bay for around 600 . First  I have heard them mentioned here .Has anyone else had experience with them? sounds like Jim has a bad experience.Maybe simple fix:inquiring minds want to know..under ST generator head..have engine would build own gen set..

[NeoplanAN440]

hi,
im running a st5 on my Listeroid and a st12 on a Witte.

have you checked allready the brushes and slip rings??
does your head allready have the AVR??
weak point on these is mostly the bridge rectifier!!

check for ac voltage in front of the rectifier and dc voltage going to the brushes!!

[NeoplanAN440]

if you have no power on these connections,

remove the two field wires from the rectifier (AC side) and check resistance!!

then you can check the resistance on the rotor (DC side of rectifier)
or remove brushes and check on the slip rings!


if these are all there,i can walk you trough how to energize the rotor field via a battery!!!!

but two years sounds not likely that you need to do that!!!

as said,newer heads have problems with failing AVRs (you dont need that)
or the old design has bad rectifiers!!



i had one failed rectifier in 5 years of running up to 12hrs a day.
i removed the AVR on all my setups,as the st is stable enough as it is!!!

[Sean]

Does your head look like this?




-Sean
http://OurOdyssey.BlogSpot.com

[berrybus]

yes the picture is it. thanks jim.

[Just Dallas]

Removed

[Sean]

Please open the terminal box and tell me if you have a single jumper/strap between U5 and U6, or a pair of jumpers/straps, one U1-U6, and the other U2-U5.  Or also let me know if there is some completely different combination of jumpers.

-Sean
http://OurOdyssey.BlogSpot.com

[Sean]

Is that the Harbor Freight Generator head? It sure looks similar, even though it's a different color.

Dallas, the picture shown is a Dong Feng.  I believe HF sells Chicago Electric.

-Sean
http://OurOdyssey.BlogSpot.com

[Chopper Scott]

I knew a guy named Dong Feng that painted people's faces on a grain of rice. No wait..... it was Hung Lo and he painted your face while you ate rice.... I can't keep em apart. CRS I guess..

[Hartley]

I have 2 of the ST-10 Generator Heads.

According the the manual that I once had, all you had to do to
re-magnetize the fields was to momentarily hook a 6 or 12 volt battery
across the output leads (120/240) for a second or three.

That would zap some residual magnetism back into the armature.

That's all I have ever had to do even after sitting for a long time.

All ST-Heads are basically a universal design, not much different
between them other than capacity. They all run @ 1800 rpm. They
pretty much are built like a battleship and very heavy.

I bought mine from the same supplier as the Changfa diesel engine
that I have on one. The hardest part is hand cranking a horizontal
diesel engine and still being able to walk 5 feet afterwards.

Dave....

[Sean]

According the the manual that I once had, all you had to do to
re-magnetize the fields was to momentarily hook a 6 or 12 volt battery
across the output leads (120/240) for a second or three.

This is not correct.

To flash the field, a 12v battery must be connected between terminals F1(+) and F2(-), not the output terminals U1 and U2.  The battery must be connected briefly while the generator is already rotating at rated speed.  You should see the output come up to rated voltage almost immediately as the battery voltage is applied at the field terminals.

Again, if the generator was working when last stopped, I don't think this is a residual magnetism problem, especially since the OP already stated he tried flashing the field.  But it could be, and he might have done something incorrectly, such as reversed the battery polarity.

-Sean
http://OurOdyssey.BlogSpot.com

[Hartley]

Must have been the translation from chinese to japanese and then to spanish then to english.

I have never flashed a field with a generator running and wouldn't due to
shock hazards, The field voltage jumping up to 63 volts suddenly and full
output appearing on bare terminals is not the way I would want to start
or stop my day. I really don't like letting the smoke escape.

Sorry Sean,

[Sean]

I have never flashed a field with a generator running and wouldn't due to
shock hazards, The field voltage jumping up to 63 volts suddenly and full
output appearing on bare terminals is not the way I would want to start
or stop my day.

If the generator is not spinning, merely putting voltage on the field terminals will not accomplish the task.  In fact, it is further necessary to put a load on the generator in order to get the full effect.

The ramp-up to the full 63 volt field voltage is the reason I usually recommend using a good pair of insulated gloves while holding the leads against the terminals.

-Sean
http://OurOdyssey.BlogSpot.com

[Hartley]

Not to mention wearing a tie and long sleeve shirts.
 
My ICD/Pacemaker wouldn't stand for much nonsense these days anyway.
After getting slapped around 6 times by it, I try not to antagonize it too
much.   Much like getting hit by lightning repeatedly.

I see your point & technically but everyone has their own way I guess.

[berrybus]

well men i got up with my lower back in bad pain this morning. it might be a day or two before i go to the garage test the wiring.thanks jim.

[robertglines1]

did you get your front slide worked out?

[berrybus]

yes im getting there slowly with front slideout. with the farm and my dad being sick its ben slow. thanks for the help jim.

[berrybus]

well im not having much luck. i found a place called utterpower who has a kit to replace the dog house witch needs to be replaced anyway but i cant seem to send them email. any one heard of them?they make it look simple. the generator has 10 wires coming out of the top 2 are to theslip rings 2 are marked the rest im not sure. i cant find any voltage on any wires. not sure what to do next. thanks jim.

[Sean]

Jim,

I've had the manual sitting open here for a week waiting to hear back from you.  If you answer the questions I asked you in my last post, I can try to help you.

-Sean
http://OurOdyssey.BlogSpot.com