LOST JEEPS
http://www.lostjeeps.com/forum/phpBB3/

Good news / bad news
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=42667		 Page 1 of 1
Author:  danoid [ Tue Apr 28, 2009 9:20 am ]
Post subject:  Good news / bad news
Had a power outage recently...

The good news: 52.5 run hours on generator and 8.3 gallons used = approx 6.3 hours / gallon.

The bad news: I left a window open on the KJ and the wind was blowing the exhaust in the wrong direction. It now absolutely stinks of gas exhaust. PATOOIE!
Author:  Joe Romas [ Tue Apr 28, 2009 1:30 pm ]
Post subject: 
I have three diesel generators, 5500, 3500 and 3000 watts continious. (they are some of my toys :lol: ) The air cooled Chinese copies of Yanmar's and they don't exactly smell like roses :roll: The bigger one, 10 HP, is rated at 9 hours 50% load on 3 gallons. (or 1 gallon per 3 hours) So in your case that would be about 17 gallons :shock: When Ike came through here last August that was about how much fuel I used per hour but I ran it 3 hours on/3 off and that kept the refrigerators cold.

How did you get such good fuel "mileage" out of a gasoline unit or was it a small one when I only got/get 3 hours per gallon on #2 diesel :?: I had a 7000 watt gas Generac I sold my daughter and son inlaw and it drank gas like a fish during the outage.

Edit. I forgot I have a 1000 watt Kipor inverter smart throttle unit that has ratings close to yours :D
Author:  geordi [ Tue Apr 28, 2009 3:09 pm ]
Post subject: 
I have a gas Generac 7kw on my RV, and that thing is "rated" at 2 hours per gallon... BS! It GULPS fuel, running a gallon per hour no matter what is loaded onto it. I usually run it full-time when I'm driving someplace, so I just leave both roof airs pulling on it since there isn't any sense in only using just one.

But I rent out a 25kw diesel genset that at FULL BURN of 60 amps, was only using 1 gallon per hour (probably less) and usually is FAR less than 1/2 gallon per hour, which is it's rated "half load" usage. It's rated at 2 gallons per hour for full burn, but maybe that is at 3-phase. I don't know, I only pull single phase from it.

I want to own that big boy tho. For hurricane season, that thing would be a joy to have around. I rented it to a film that put 33 hours onto it and it only took 12 gallons to fill it back up. Hows THAT for economy!
Author:  grywlfbg [ Tue Apr 28, 2009 3:31 pm ]
Post subject: 
I have a little Honda 2kw that runs about 8 hrs on 1 gallon. I just needed something for tire warmers when racing but if the power drops it'll run the fridge just fine. Also has an inverter so can throttle way down when the load drops.
Author:  geordi [ Tue Apr 28, 2009 4:20 pm ]
Post subject: 
Can you elaborate on that inverter? I thought that generators have to remain at a set RPM in order to generate the right frequency. That makes sense to me for a diesel genset, as the RPM can be maintained while drastically cutting the fuel input when the load isn't present. Gas designs are much more limited because of the stoich fuel mix that has to be maintained or the engine will be damaged.

How do these inverter designs work?
Author:  danoid [ Tue Apr 28, 2009 8:22 pm ]
Post subject: 
Mine is a Yamaha EF3000iSEB. It's a 3000W inverter with variable engine rpm/throttle, but the kicker is that it will pull from the 12V starter battery for surge currents. (Yamaha says about 3500 watt surge) Ran both my fridge and freezer fine, then the kids turned on the TV...and still fine.

It was expensive for a low/mid power generator, but it's very quiet and I don't worry too much about fuel.
Author:  Uffe [ Wed Apr 29, 2009 3:31 am ]
Post subject: 
geordi wrote:
Can you elaborate on that inverter? I thought that generators have to remain at a set RPM in order to generate the right frequency. That makes sense to me for a diesel genset, as the RPM can be maintained while drastically cutting the fuel input when the load isn't present. Gas designs are much more limited because of the stoich fuel mix that has to be maintained or the engine will be damaged.

How do these inverter designs work?


Inverter designs take the voltage from the generator, rectify it, filter it, make it into a nice smooth DC voltage. Put that onto some capacitors and use a PWM modulated signal to run a set of powertransistors (IGBTs) to make whatever voltage and frequency you like, from that DC voltage. Then it doesn't matter what voltage or frequency you put into the system, the output is controlled using electronics and control software. The engine can then run optimally all the time.

All you need to make sure is that the input power to the DC-link (motor power to generator - losses) is the same as the losses and the output power of the inverter.
Page 1 of 1 All times are UTC - 5 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/