Author Topic: Metro 4Kva gen head 6/1 Metro  (Read 27122 times)

behoof

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #30 on: March 08, 2010, 04:38:34 AM »
I had a 7.5KW Metro genset from Sam that had a 12HP Petteroid direct driving a Indian genhead.  I think all the Indian made genheads are series wound generators; all the load current flows through both the stator and rotor!  The diode groups form a full wave rectifier to keep DC flowing through the rotor so that it has constant North and South poles; also the more current you try to pull through the generator the higher the output voltage goes, within some design limits  ;) of course.  These generator heads are center tapped so you can have both 120 and 240, but I think you only get 1/2 the rated output at 120V  >:( !  They can't be rewired to get full output at 120V like a ST genhead as far as I know.  Of course I don't know anything for certain since I haven't seen your unit in person.  The genset I had worked very well, I could load it up very heavy and the output voltage just kept rising and it would start my compressor or swamp cooler even when overloaded but the Petteroid was blowing black smoke and the frequency dropped way down past where the Kill-o-Watt would give a reading.  The weak spot in these style genheads is the diodes, that's why they give you extras with the generator (you did get extras with yours, right?); I was always afraid of blowing a diode when overloading my generator for a test so I only did it a few times for short periods.  The diodes stayed cool to the touch as far as I could tell and they were in the airflow of the cooling fan.  Still I wonder what would happen if a diode was to fail and be a short?  Maybe this type diode never does fail into a short and just pops open?  I didn't want to find out so when a guy needed a generator in a hurry I sold the unit to him; the direct injection Petteroid was way too noisy for me to use in my neighborhood.  The Listeroid 6/1 is the least noisy diesel that I have ever heard so far  :) !  Leland

Thanks for all the info, and I may just follow your lead on this... I have a feeling that this genset may just become available and a new one may very well be in my future.

I just love my Lister, I made an expansion chamber for the exhaust and it made it a lot quieter, all I hear now is the fuel system and a bit of machine noise... no biggie, I like that racket LOL

Have to list it somewhere and leave it hooked up as is so the new owner can see it run. It really does work great, on both legs and 220v but I'd really like to have all the power available in the 110v range... oh well, on the next one.

I built that permanent magnet alternator for wind power but it's 3 phase and I use those for battery charging but I do like the PM gen's/alts for simplicity.

I really do have too much fun...

Thanks a lot for the great reply, very informative

Thanks to everyone, I just hope as time goes on I can share also.

behoof

behoof

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #31 on: March 08, 2010, 04:44:43 AM »
I agree totally with your Line at the bottom... can't weaken or give in <period>

I had a piece of unwelded then galvanized Chinese chain come loose on one of my windmills and it made a 1 foot hole in the ground when it hit...

broke my heart BUT, it'll be going back up this Spring better than ever!

Can't let the Bast**ds get you down as they say.

Would still love to see a schematic on this thing, especially after reading these great posts on how it works. Would love to see what the rectifier is doing and how they have this thing wired. It's hard to get a decent look inside, you can't even get the lid off without clipping stuff. Ahhh well, more fun for me.

Yep, diodes go pop and open... let's hope I don't find out about that.

Thanks,
behoof aka skipb

Doug

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #32 on: March 08, 2010, 10:06:21 PM »
There is nothing to see.....

Its a copy of an old English style head. Its basicly an ST head that inside out and it rectifiies and pulls current through an aux coil in the field ( not all that different from other styles designed in the same periode )
It's a Good Life, If You Don't Weaken

behoof

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #33 on: March 10, 2010, 02:00:30 AM »
THANKS EVERYONE,

Appreciate all that great replys and shared knowledge. I'm at a point with my question now where I've decided that this generator will be as it is. I'm going to make it available or keep it for a spare.

Now for finding another generator for my 6/1, one that I can have devote all its power to the 110v side, as stated above not interested in 220v.

Anyone have any ideas on which generator (PM alt, U frame, ST etc) they would advise, I'd sure appreciate the insight.

Best to all,
behoof aka Skipb

Doug

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #34 on: March 10, 2010, 06:00:51 PM »
U frame??????


U frame is a pre 1962 standard for electric motors and generators running lower than modern flux densities and insulation types at or below 105 c. A generator bu8ilt to U frame specs is probably out there but it holds no real advantage too you other than its a bit cooler to the touch, quieter in opperation and unfortunately lower efficiency.

A Pm alternator is a lot like a car with no gas pedal you.

An ST head is just a brand new old thing....
It's a Good Life, If You Don't Weaken

behoof

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #35 on: March 11, 2010, 01:12:23 AM »
U frame??????


U frame is a pre 1962 standard for electric motors and generators running lower than modern flux densities and insulation types at or below 105 c. A generator bu8ilt to U frame specs is probably out there but it holds no real advantage too you other than its a bit cooler to the touch, quieter in opperation and unfortunately lower efficiency.

A Pm alternator is a lot like a car with no gas pedal you.

An ST head is just a brand new old thing....

Thanks Doug,

Pretty much as I understood it... except that I really liked your analogy for the PM Alt ... good one

behoof

NoSpark

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #36 on: March 11, 2010, 02:29:00 AM »
You mean like a Toyota?  :D
Anand Powerline 6/1 ST5

behoof

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #37 on: March 11, 2010, 02:38:03 AM »
You mean like a Toyota?  :D

Ya know? Come to think of it, Perhaps? Just Perhaps the throttle linkage in the Toyota's was made in India???

Ya Think?

NoSpark

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #38 on: March 11, 2010, 02:54:50 AM »
Throttle linkage? Everything is fly-by-wire now. Could still be made in India though, yeah.
Anand Powerline 6/1 ST5


Doug

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #40 on: March 11, 2010, 07:16:43 PM »
Nothing wrong with drive by wire.
AVRO was using it on airplanes in the 50s ( as were many companies ).
The real question is the software
It's a Good Life, If You Don't Weaken

behoof

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #41 on: March 11, 2010, 11:35:15 PM »
Yeah, drive by wire is cool... I drive a 96' Ford 7.3TD and everything on that truck is "by wire" no biggie really... I'd really hate to see me have the Toyota Disease get this Ford... there'd be NO stopping it, <period>

lowspeedlife

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Re: Metro 4Kva gen head 6/1 Metro
« Reply #42 on: March 13, 2010, 06:07:01 PM »
I'm still not convinced about toyota's "problem", they may have had some sticking gas pedals but for sure the guy going 90 MPH in california last week is bull crap. He repeatedly stated he was too affraid to to take his hands off the steering wheel to shift the car into neutral or push the on/off button, (both are four inches from the steering wheel) but then said he had reached down to try to pull up the gas pedal at 90 mph. I'm 6'3" with pretty long arms & can't reach a prius gas pedal when it's in the up position. (friend has one & i tried it). This guy has financial "issues" too, & has been on game shows (think "Balloon boy") one of his creditors is toyota. It's a shame that our news media has sold itself out to become "the national enquierer" instead of a real investigative orginization. Hell, the Enquirer broke the John Edwards love child story & the news orginizations ignored it for months during a presidential campain!!, 30 years ago that would never have happened.


  Scott R.
Scott R.

5.7 liter diesel k-5 blazer. converting to wvo.
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