Your last generator Maintenance Run

[3930dave]

90 - I suspect what you are pondering is what looks to be Hour ratings, under different test Classes.

Bigger stuff ^ than the caps I used to work with (down into the detail-weeds @ times), so I don't know those Classes.

No promises, as it is the Holidaze @ moment, but I'll ping a retired buddy of mine, as there is a decent chance he is familiar with those Classes.....

Rgds, D.

P.S. Ducati ! I'm so used to seeing red !

90 - got an email back today, from my Power Electronics buddy..... (Thanks GC !).

"As far as I know, the "Classes" listed refer to the lifetime rating, lifetime ratings also happen to be listed on the capacitor (redundant info). Good info for an electric motor run capacitor.
Assuming that is a "run" capacitor, as the low cap. value suggests, lifetime would be critical as the cap is always passing current, generating heat and internal gas pressure - i.e. wearing out.
A start capacitor is usually a higher uF value."

Rgds, D.

 

[90cummins]

Thank you!
90cummins

 

[90cummins]

Brushless generators use capacitors for voltage regulation. All you need to do is match the uf and voltage class rating….. I’ve even used slightly different uf rated capacitors when exact replacements can’t be found, and they work fine…maybe a volt or 2 more output.

Does increasing the uf increase or decrease voltage output?
Good info

90cummins

 

[grsthegreat]

Increases voltage a bit as you increase uf, but that was when I only increased one from 78uf to 80uf. Not sure how healthy for gen though

 

[kenmbz]

Don't change the cap value too much, it goes on an inductive load.

 

[grsthegreat]

Don't change the cap value too much, it goes on an inductive load.

Agree, but they stopped making the 78uf required one for the generac 10kw brushless. I went with a 80uf out of necessity, and it worked out ok. Figured they have a 5% +/- rating anyways.

 

[daugen]

GRS, would this be a decent deal?
my neighbor's son is in the business and could install it for me
would want to find out why pulled out

https://philadelphia.craigslist.org/grd/d/perkiomenville-17kw-generac-standby/7902407131.html

 

[Carl_NH]

Hi Daugen,

I just installed one very similar that only 8KW 161 hours, a 2018 model, though but it was free! My neighbor, a contractor, was remodeling a house, new owners wanted "everything" connected so pulled it out. I did wire it for 75 amps if we decide to replace it in the future,

We installed a new ATS, and bigger LP tank, and did the trenching, electrician and gas co did the connections - all in $6K (with a $1K new tank). Runs great and clean power.

Up here, these units go for $1-2K barely used. I guess people want to add the AC, or enlarge their system. Seems like a waste of $ but I was happy to get a whole house unit,

 

[grsthegreat]

GRS, would this be a decent deal?
my neighbor's son is in the business and could install it for me
would want to find out why pulled out

https://philadelphia.craigslist.org/grd/d/perkiomenville-17kw-generac-standby/7902407131.html

That’s a good price…. But I would also wonder why it was pulled. Maybe too small for their house

 

[3930dave]

GRS, would this be a decent deal?
my neighbor's son is in the business and could install it for me
would want to find out why pulled out

https://philadelphia.craigslist.org/grd/d/perkiomenville-17kw-generac-standby/7902407131.html

Nice size/price.

Outside of the garage, firing it up on a 30# tank might be a good idea.

Rgds, D.

 

[daugen]

That’s a good price…. But I would also wonder why it was pulled. Maybe too small for their house

thanks
I'd want a guaranty of decent operating condition if bought from a company
I have a 900 sf cottage with one small hvac
probably the right size
I run it all on 9kw now with the hot water heater turned off but it struggles at times

I think with the "reasonably" priced models up to 24kw now, going up from 17 to 24
might have been what someone needed with multiple hvacs. Or a new hot tub.

 

[grsthegreat]

Nice size/price.

Outside of the garage, firing it up on a 30# tank might be a good idea.

Rgds, D.

For a test maybe. It will freeze a small tank of fuel

 

[3930dave]

For a test maybe. It will freeze a small tank of fuel

Understood, @ Load.

Perhaps also a large enough pail to sit a 30#'er into hot-water for the short test ?

Rgds, D.

 

[Fallon]

Understood, @ Load.

Perhaps also a large enough pail to sit a 30#'er into hot-water for the short test ?

Rgds, D.

That's a standard work around for blacksmiths on gas forges. They freeze up due to rapid use too. As long as it's warm not boiling your fine. Some use a torch or heater, but that's pretty dangerous. If it's just a short test like 5-10 minutes you probably won't need to bother with anything

 

[3930dave]

That's a standard work around for blacksmiths on gas forges. They freeze up due to rapid use too. As long as it's warm not boiling your fine. Some use a torch or heater, but that's pretty dangerous. If it's just a short test like 5-10 minutes you probably won't need to bother with anything

Makes sense (not the torches etc....) . Increase in tank area (@ Cold Ambient) is one reason for dual-manifold tank setups, ie. on RVs, and IIRC, somebody built one on here for their small gen.

I understand some of the general thermodynamics, and have seen my HVAC buddy do same (water/pail) with refrigerant.

d seems to have found a good deal, and may have been working fine when pulled, but nothing beats actual operation and check of fundamentals....

Rgds, D.

 

[90cummins]

I had mentioned earlier that the regulator on my Neihoff 28 volt alternator was bad and I was undecided on how to proceed. Being a fan of market place I found a 5500 watt belt driven generator with a Yanmar hopper cooled diesel mounted on a very nice frame.
I picked it up for $250 brought it home and with a bit of love got it running and did a test run when the generator stopped working.
Inspection found a bad capacitor and TBN helped me find one that works very good regulating at 120v at 60hz.. I also replaced the 3 pole 240v outlet with a 30 amp 4 pole 120/240 outlet.
A google search originally identified the engine as a Yanmar NS10 however further looking found that NS65G is cast into the back of the flywheel.
After giving the injection pump some love and 4 oil changes and several oil filter cleanings I ran it loaded 2.7kw for several hours in preparation for load and fuel consumption testing.
The engine runs at 2200 rpm and the belt driven generator runs at 3600rpm.
It handles a 2.7 kw load nicely but the governor not as accurate allowing the engine to run up to 2500 rpm (68)hz when unloaded.
I have determined that 3.5kw is the maximum load the engine can manage.
The engine is hopper cooled with water and is NOT pressurized but has a condensing radiator on top with a belt driven fan which cools, condenses and recycles the water. During extended full load runs I have not observed steam escaping from the vented overflow tank.
This engine is started with a hand crank that I’m unable to manage so I use my Milwaukee magnum drill and an adaptor to & start it.
Fuel consumption is approx 18-19 grams per minute with a 2.7kw load.
If my rusty math is correct it would run 2.9 hours per gallon with a 2.7kw load (3.618)hp.
Based on my limited time with this unit it would not work as a stand alone backup because of the poor governor speed control however it would work fine as an AC supply for my inverter because the inverter would condition the input power and provider true pure sine 60hz output voltage.
Because of the low operating speed of 2200 rpm I would not hesitate to run this for days if needed.
I was having very little luck in finding information on this engine until bmaverick from TBN saw my post.
The information he had at his fingertips and his recollection of data was truly impressive.
That’s it for today 90cummins

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