# Any one use ST Generator head from China



## solidwoods (Dec 23, 2005)

Howdy
I'm shopping 30kw gen head . Anyone know the average hrs. that the brushes will last?
Thanks
jim


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## Johnny Dolittle (Nov 25, 2007)

I thought they all went to brushless ???? Or are the Chinese old school yet?

BTW About ... 4-5 years ago I read about some outfit in Canada importing Changfa lister style diesels and generator heads realized the Chinese grease in the bearings in the generators was very sub-standard and they recommended replacing it.


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## ace admirer (Oct 5, 2005)

well i dont have many hours on mine, but the ring and brushes look pretty heavy duty, like a 1945 design, 

i did wash and replaced lubricant.


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## solidwoods (Dec 23, 2005)

I'll repack the grease also, may as well it's not real hard to do and if one goes/locks up one may have a pile of parts.

That's one thing that can be said for Communism , it builds very simple equipment and in China's case Billions of'em.
Now Cubas problem is when communism falls the locals will be endanger from the vacuum created by the old vehicles being bought up and shipped out. The island may rise out of the water giving them a little more beach.ound:

JD
I'll E-look around brushless (besides what I've found so far)


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## justin_time (Dec 2, 2012)

I wouldnt just regrease the bearings, the fact your doing that makes me think these have open raceways. Take a look at the cooling fan blades ,Those ST heads move a lot of air, those open greased bearings are a magnet for dirt and dust. Pull the rotor right out and knock the bearings off. The bearing numbers should be on the raceway.Phone some bearing supply houses with those numbers but tell them you want sealed bearings. NSK brand is what I suggest.Do not use Chinese bearings, I am sure they can make good ones, I have just never found any. Since you have the rotor out spray on a good coat of glyptol.
Nothing wrong with the ST heads, in fact a solid,bullet proof, hackable, design that can be easly repaired. I highly recommend them for stationary use. They will punch out way over their name plate rating for starting heavy inductive loads, and so ---- heavy no one will steal one.

To answer your question about brushes thats hard to say but I cant imagine less that 3000 hrs likely lots more, but every one I have bought has come with an extra set of brushes.In regards to buying a 30kw head, I can only say, wow, how many homes do you plan on running? thats going need a 55-60 horse Diesel to drive it!

PS, just remembered, I do have one, a 5kw ST head that I did just replace the grease in(before I knew better). It has maybe 300 hrs on it and I can hear the front bearing grinding now.


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## solidwoods (Dec 23, 2005)

JT
Thanks I'll check the bearing type. I wouldn't guess they are not sealed bearings but checking is one of those really cheap things that one can do to avoid trouble.

My energy need is 20kw max. I'm using a 30kw head to I don't run it hard/hot. I have a large hot water need so with load sensing I can off/on some water heating elements. This is quite beneficial to gasifiers also because they can be tuned to optimize the gasifiers performance.

Brush hrs. I'm asking around and so far I've found a range of 800hrs (an ebay seller of the 30kw) to 3k hrs. 

I'll have to look up glyptol to see what it is.


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## justin_time (Dec 2, 2012)

800 hrs, is a fail, I would be asking why such a short life span, and there are reasons that I will get to, but first I have to tell you that I too can produce hot water but I would never do it electricaly as I get more hot water from the cooling of the Diesel. Even a little 5-7 hp water cooled Diesel will produce hot water faster than it can be used. One of my gen sets has the engine making 4 hp, and the alternator is loaded to 1500 watts, I have steam coming off the 30 gallon cooling tank in about 30 minutes.
Also using a over sized head as likey you are going to do, means greater losses powering the field windings. Dont get me wrong, it will absolutly work for you, but my concern is getting the most power out per litre of fuel burnt, a big concern with fuel costs greater than 4 dollars a gallon, maybe not such a concern where you are.
Regarding brushlife, 3 thousand hours would be the minimum I would expect to get on any slip ring/ brush type alternator running at 1800rpm, which is what the ST heads run at.
I would rotate or have someone rotate the shaft while I looked at the brushes, you want to be sure they are running centered on the slip rings, if not adjust the holders (I have never seen a ST with the brushes centered right, then you want to check for brush bounce as this can really shorten brush life. With someone spinning the shaft put one finger on a brush and watch another brush as the shaft is spun. If you can feel and see the brush moving in the holder, you have a problem. Ideally they should be rock steady-no movement. You can have brush bounce for a number of reasons, worn bearings, or crap new ones, a bent rotor shaft,I have found the usual cause on these type unit when new is just that the slip rings have not been machined true, or machined down enough(easy to fix). Just sometings to check if you only get 800 hours.


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## Darren (May 10, 2002)

I'd be more concerned with the quality of the insulation on the windings. If it's USA built, you can rely on the NEMA classification. From China ..... it's like that Johnny Cash song where he pages Ben Dover.


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## justin_time (Dec 2, 2012)

Darren said:


> I'd be more concerned with the quality of the insulation on the windings. If it's USA built, you can rely on the NEMA classification. From China ..... it's like that Johnny Cash song where he pages Ben Dover.


 
I havent found a problem with the quality of insulation, though glyptol will improve it, I have one thats been outside since 2005, and no problems.I agree a North American build ST head would be great, let me know when you find one!


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## solidwoods (Dec 23, 2005)

JT
If you will read my above posts you will see I'm not using diesel , I'm using a gasifier that runs off of dry organic material.

You'll also see that I use allot of hot water for many many reasons.
I'm not just a homeowner with small energy needs. I'm 2 businesses that use allot of hot water, a 1000sf greenhouse with 1500gl aquaponics system water at 80deg, and I'm heating 2 homes.
So I'll be using engine coolant and an exhaust gas/water heat exchanger from the engine, gasifier filter/cooler water and electric heating elements to keep the electric at a steady draw rate (around 20kw total). But steady draw rate is down the road because that in it's self is a bit of work.

I'll check the brush alignments and check for bounce, thanks.

I have to tell you that I too can produce hot water but I would never do it electrically as I get more hot water from the cooling of the Diesel. Even a little 5-7 hp water cooled Diesel will produce hot water faster than it can be used.


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## justin_time (Dec 2, 2012)

Your mention of gasifier didnt register, guess fuel costs wont be a problem then. What type of engine do you use?


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## solidwoods (Dec 23, 2005)

I'm using a gas 4cyl Ford power unit with a hand operated clutch. It is on an Asplundh chipper. I don't know the cid of the engine. I'll take some pics and try here and some other areas on HT to see if anyone can help ID it.
jim


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## fordy (Sep 13, 2003)

solidwoods said:


> I'm using a gas 4cyl Ford power unit with a hand operated clutch. It is on an Asplundh chipper. I don't know the cid of the engine. I'll take some pics and try here and some other areas on HT to see if anyone can help ID it.
> jim


................1 Hp=746 watts , so 30,000 divided by 746 = 40 Hp. ! , fordy


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