803A first run and hertz question

[jimbo913]

Well, I finally got everything wired and since it was a nice day I figured it was a good time as any to verify proper operation before power gets knocked out.

I connected it up and after a 5 min warm-up I adjusted hertz and voltage prior to switching over to generator power.

Initial load was only registering around 5%, but everyone was outside and mostly nothing was on except small pool pump and all the phantom loads. I turned on the dryer and it jumped up to 50%. I noticed that the hertz had dropped to about 55 or so (lower than expected) but voltage held fairly steady (+/- 1-2v). I readjusted the hertz to 60 and flipped on my downstairs AC unit. I expected a surge but heard none. I checked the voltage and hertz and both were steady but the load was up to 75%.

I let it run awhile at 75% and then turned off the AC, dryer and switched back to line power while I let the generator cool off and then I shut it down. Total test lasted about 15 mins because I had some other stuff to do. The generator did take awhile to idle down (about 25 seconds) until it fully stopped running.

Anyway, it looks like the 803 can likely run both my AC units and normal loads. Rarely would we ever need to dry clothes on gen power and that could easily be done at night so we should have plenty of power while not being too over powered.

Question: Shouldn't the hertz be able to hold steady from 5% to 100% rated power? Am I missing something in the setup such as it needs to warm up longer prior to adjusting the hertz and/or voltage?

And how long should these take to shut off?

Jim

 

[jimbo913]

Doubt I will ever hook the generator up via auto transfer given the requirement to manually adjust the hertz. Seems like each time I start it there is some fine tuning needed for hertz and volts. I have only started it 3x and only once with any load.

 

[DieselAddict]

The governors on these units are mechanical so there will always be some droop. If you have to adjust it every time or if the droop is too much you will want to check all the linkages for binding or friction. My 802s gain a little RPM as they warm up. I don't bother adjusting every time I start since I know now they will rise up after they run for a few min. I get about 2-3hz droop from light load to full load.

If its taking 25 seconds to wind down after you pull the kill switch you aren't getting full fuel cut-off. Can you check to see if the fuel cutoff solenoid is full screwed in?

Edit - Corrected the droop number. One line on the gauge isn't one hz.

 

[jimbo913]

When you say pull the kill switch, is that differnt than just turning the master control knob from run to off? I didn't try pulling the emergency stop.

 

[DieselAddict]

Sorry, Yea. I meant turning the control knob to off.

 

[jimbo913]

I can't post a photo from my phone so will follow up when I can via PC. The gap between the nut and the end linkage is about 1/2 thickness of the nut or less.

 

[jamawieb]

A good running unit should only drop 1-2 hertz. Some units that have more hours will drop 3-4 but 5 is a little to much. I would adjust the governor and set you're hertz to 61-62 hertz with no load. Most electronics can take an increase in hertz but if you drop below 57 for an extended time, you'll do damage to them.

 

[jimbo913]

Thanks. I will read up on the governor and fuel solenoid adjustment. The unit only has 11hrs since reset so most likely tight linkage or adjustments are causing the issues.

 

[jimbo913]

I stand corrected, it was actually only about 2.5hz fluctuation because the gauge is .5hz per line like DieselAddict stated. It moved about 5 lines and in my mind I was thinking 5hz.

I will mess around with the fuel solenoid linkage..

 

[zarathustra]

Generally one can expect droop between no load and max load. However I'd expect that one could set the cycles a little high at no load to compensate for the "loaded droop". I believe that is SOP.

As far as taking some time to slow to a stop -- some take more time than others, but once the electricity is off the fuel pump stops pumping and the fuel pressure should drop to near zero almost immediately. Now if the pressure isn't dropping immediately then I'd suspect a blockage in the tubing that returns fuel to the tank or that "manifold" that comes off of the final fuel filter. It should have a nozzle (restriction) on the far left of the metal manifold where it connects to the rubber re-cycling hose. That nozzle is a passive piece that keeps the pressure in the manifold constant.

Note that the pump is a low volume high pressure pump ~50 psi. The Aux pump is just the opposite -- low pressure high volume.

I suppose that a maladjustment of the fuel solenoid could cause this problem, but as long as the rod/bar on the shutoff is moving smoothly it should shut off.

Are you sure it takes a full 25 seconds?

 

[jimbo913]

Thanks, some good info in that post.

I didn't exactly time it during shutdown but it seemed to take a long time and was double what it took the first two times I started it but those times I never got it warmed up. Even then it seemed to take a long time. It was long enough that I wondered if it would shut off. Maybe she gets really good fuel economy!

I suspect its just the linkage binding but it feels loose. What I need is to get someone to shut it off while I watch it. Easier said than done with a house full of females. I tend to always try and figure out how to achomplish tasks alone..

 

[Ratch]

What I need is to get someone to shut it off while I watch it. Easier said than done with a house full of females. I tend to always try and figure out how to achomplish tasks alone..

Use the dead crank switch. Throw it to center position and it should be like hitting the emergency stop button. There should be no ill effects from this as long as you don't have it loaded (and even then, I can't think of how it would be different than a normal shutoff).




That will essentially drop 24v dc to everything, deactivating the solenoid (deactivating it is what makes it kill fuel).







Theoretically, you could also unplug the solenoid while its running, which would make it go to shutdown state.





Every time I exit the thread, I think of something else...


You could also disconnect the solenoid linkage, open the fuel lever fully, turn the master switch to run primary, then instead of start, hit the "crank" position on the dead crank switch to start the engine, then once running stable, manually rotate the lever to kill fuel and see how it dies.





And yet more...you could disconnect the solenoid linkage, and make sure the core moves freely. It's possible the rod has corrosion (if the unit sat unused for a long time) than needs cleanup. I'm not sure how I'd lubricate it if necessary, I typically would rather rely on polished surface than a grease that could solidify without lots of usage.

By the way, don't forget about the fan blades and moving parts when monkeying around with it running.

 

[jimbo913]

Ok, so I took a little better look at it and from the side the linkage looked fine and felt loose enough, but from the top you can see it is bent a bit, so I will definitely remove it and straighten that out but the odd thing is that when you manually push or pull the solenoid rod, it only rides in one position of that slot and it returns fine.

 

[Dewie38]

Spec on the 802 and 803 is for them to shut down within 30 seconds, if it shuts down in less time don't worry about it.
The difference between no load and full load speed is 1.8 Hz or 3% (3% of 60Hz).
The difference between no load and full load, some times called droop or frequency regulation, is adjustable by removing the 8mm allen screw on the side of the engine (it is right in front of the shutdown solenoid on the front cover of the engine).
With the set running at full load and 60 Hz remove the load by opening the set circuit interrupter. The no load speed should be no higher than 61.8 Hz.
If it is shut down the set remove the 8MM allen screw (it is just a plug that allows you to get to the adjustment)
With a 5mm allen wrench turn the adjustment clock wise about a quarter turn. One full turn is equal to about 1/2 Hz.
Replace the 8mm allen plug (running with the plug removed will give you an oil bath).
Start the set and apply load again and adjust speed to 60 Hz remove the load and see what you have at no load.
Repeat as necessary until the droop is about 1.8 Hz. (1.6 or 1.5 Hz is acceptable).