Low voltage on st 10kw head

[Toad]

I have a 12/2 and a 10k St head.  When I set my cycles to 61 my voltage drops, It may drop as low as 200 volts under load.  The unit is new and only has about 50 hours on it,  everything seems to work ok but I am worried that this is to low of voltage.  Is there anything I can do to increase the voltage?  Do I need to have a voltage of 220 to 230?   This unit has an AVR and it is turned up as high as I can get it to go.  I have tried removing the AVR,  I had  the same results.  Any suggestions would greatly be appreciated.
 

[rocket]

check the temp on both cylinders... you may be running moslty on only one. also check the rpm of the engine under load ... it sounds like the fuel rack is open but the engine is not keeping up the rpms. if both cylinders are the same temp... but the rpms still drop under load i would check it isnt overloaded and if thats good.. possible timing... but being a twin.. first bet is you are only firing on one strong

[Geno]

Get George's CD if you don't already have it. http://utterpower.com/utterpower_cd.htm  Read his website (Its semi organized) And use learn how to use search option on this website. The answer is almost always out there several times over. If these computer things are not your thing we'll be happy to help you further.  Poor gov response is a cronic issue. 200V is to low. Details and all t-shooting steps performed are always helpful.

Thanks, Geno

[Jim Mc]

Right.  As Geno says, the 1st thing to do is figure if the low voltage is caused by low engine speed under load.  I'd suggest getting either a tachometer or frequency meter, and see how much droop you have in the governor.

[Toad]

I curently do not have a kilowatt but my clocks are running a little fast and my washer wont work unless the rpms of the motor are turned way down.  If I get everything running correctly the voltage on the generator is to low.  I can turn up the motor and increase
the voltage but some items wont work and my clocks will increase by 30 to 40 min over night.  The motor seems to run good at the lower rpm setting and everything in my house works ok.   But I am woried about the low votage, some of my motor items sound funny when they are running.  What I want to know is how can I get more votage and is it common for there to be a voltage problem when you get the freq. set on the generator.  I have been reading about transfromers that step up the voltage and stablelize the power surges.  Is this something I should consider.

[Doug]

Again the spector of Class B1 governance raises it ugly head when what we need is A1. And it would appear India only builds A1 into a select few Petter types and no Listers that I have read about at all...

No one talks about this, and yes what we do get in a B1 is usualy substandard too

Doug

[Toad]

And what is a B1 and A1?

[Jim Mc]

What I want to know is how can I get more votage...

With these ST heads, the output voltage varies as the speed varies.

Step 1 in solving a "voltage" problem is checking the governor.

So, answer us this:  What is the no-load voltage and frequency?  What is the voltage and frequency under a 6 kW load?  Oh, and how are you measuring it?  Got a good meter?

[Doug]

ISO3046/BS5541 is a standard for governers and load regulation A1, B1. A1 is intened for generators B1 is a general purpose.

If you can get your hands on a copy of Lister/Petter Diesel Engine Theory  publication NO. 027-08649 ( provided to me by Atual Patel ) its actualy a great primer for owning a Lister Petter engine of the types we are interested. These Indian fellows know the standards, unfortunately a 400 dollar Listeroid often isn't built to meet them.

Look at this Petter type as you can see in the details it meets A1 by 4.5 % change ( 5% is the limmit )

http://kirloskarapps.kirloskar.com/kirloskar/SearchLinkFrame.jsp?Word=DM10


Now look at this Lister type. No mention of % speed change asssume class B1 ( 10%
 or worse since even a big company such a KOEL doesn't advertise how well the governer performs)

http://kirloskarapps.kirloskar.com/kirloskar/SearchLinkFrame.jsp?Word=KS6

Doug

[Toad]

I cant tell the freq. at any rpm.  I can only tell what is happening to my components when they are under load.  My generator put out 230 no load when I have the rpm set to run at what makes most of my electical stuff work.  When I put a 6 to 7 kw load the voltage drops down to about 200 to 205.  I use my digital meter and check the voltage, I have found that voltage on the st head is prety close to what I get when I check with my meter.

[Jim Mc]

OK, Mr. Toad.  I'll try once more.  We really need to know what the rpms do under load. 

It would be reasonable to assume they drop.  In that case, I'd suggest you search the forum for recent threads on governors on these engines, and make the recommended changes.

[Doug]

Hey Toad can your meter measure the frequency full load, half load and full load? This is all we realy need to get your rpm...

Doug

[Toad]

I do not have a freq meter,  I can tell my freq by the way my appliance are working.  I am guessing that I am close when my clocks
run at the correct time and my washer and dryer will work.  I have been reading up on govenor problems and I assume that is what is
happening in my case.  Everything seems to be working ok until I get a big load on the generator, like my AC.  And then the power gets puled down 10 to 20 volts.

[Doug]

The trouble is voltager is only half the equation, frequency is also important is AC loads/ The goal here is to try and get the droop bellow about 10%. You never mentioned anything about hunting at any loads so lets assume its a sensitivity problem. Try a longer softer spring ( more constant tension ) and try to adapt the govener kits described in other posts here to get any slop and binding out first.

Doug

[BruceM]

If you have a friend who flys RC airplanes, borrow his optical tachometer.  Set it for a 3 bladed prop, then point it towards some natural light through the flywheel spokes.  When it reads 1300, you're set right at 650 rpm, since you have 6 spokes instead of 3.  Check it again with a large load. If it drops a bunch, then you know your problem is a lazy governor, and that needs to be addressed.

Otherwise you're just going to have to buy an AC frequency meter.