Generator Operation Question

[AMR]

All this generator talk made me change the oil in my generator this weekend and give it a once over to be sure it is running like a champ. It took a few tries to get the correct oil filter from a small engine place so I ended up at Wal-mart picking up a Fram that finally fit.

I have an operational question. The manual states that the automatic idle control should be OFF when there are pump loads connected. Hence the generator should run wide open when loads like the well pump are on it. I tried to reason this out with an old text book, I am not an electrical expert but I think that amperage wants to head toward infinity as voltage goes toward zero, in other words, if the pump kicks on and the generator is slow bringing the voltage up the wire could overheat, does that make sense? What do others here do? What about the small fractional hp circ pumps for my heat or the small fans in my air handlers? Would those be impacted the same way?

Big difference in fuel consumption, 7 hours wide open or up to 15 hours or more in auto idle control. It is a waste as the well pump may or may not even kick on for hours at a time. I don't want to get in the business of having to turn the breaker for the well on/off and the idle control on/off, but it may come to that to save fuel.

 

[MossRoad]

All this generator talk made me change the oil in my generator this weekend and give it a once over to be sure it is running like a champ. It took a few tries to get the correct oil filter from a small engine place so I ended up at Wal-mart picking up a Fram that finally fit.

I have an operational question. The manual states that the automatic idle control should be OFF when there are pump loads connected. Hence the generator should run wide open when loads like the well pump are on it. I tried to reason this out with an old text book, I am not an electrical expert but I think that amperage wants to head toward infinity as voltage goes toward zero, in other words, if the pump kicks on and the generator is slow bringing the voltage up the wire could overheat, does that make sense? What do others here do? What about the small fractional hp circ pumps for my heat or the small fans in my air handlers? Would those be impacted the same way?

Big difference in fuel consumption, 7 hours wide open or up to 15 hours or more in auto idle control. It is a waste as the well pump may or may not even kick on for hours at a time. I don't want to get in the business of having to turn the breaker for the well on/off and the idle control on/off, but it may come to that to save fuel.

I would turn the well off at the breaker to save fuel and wear and tear on the generator.

My guess is that the well pump probably draws the most amps out of anything in your home on start up. It probably has a capacitor to help it with the initial push. That capacitor will drain immediately, before the generator can kick off of idle and then there is a huge load pulled on the generator while the engine is trying to get up to speed, etc....

I'm surprised they mentioned only well pumps and not other high HP motors like spas and pool pumps.

 

[schmism]

Big difference in fuel consumption, 7 hours wide open or up to 15 hours or more in auto idle control.

What geny? The only generators i know of that can double there run time based on throttling down (to match demand) is the small Inverter (DC based) models.

Now i know there are some larger gen sets that have a feature that idle down the motor when there is no load connected. (think a welding Genny... it idles till you strike a lead, then it throttles up) but for most home standby operation to run lights and refrigerators and TV's etc, there is usually ALWAYS a demand on it at some point (ie your meter is usually always spinning at least some) therefore its unlikely to ever idle down when there is no load. (as there is hardly ever a no-load scenario.) Remember it has to maintain a "wide open" rpm in order to generate a 60 hz frequency needed for power output regardless if its a 200 watt load or a 5000 watt load.

So in this case i would think the locked wide open and auto idle control is going to be a non issue. (your run time is going to be roughly 7 hrs period)

 

[Mighty Dodge]

I've got a Lincoln G8000 welder/gen. When using it for house power 240 volts the manual states to turn off the auto idler. The reason is the idler circuit is connected to only one leg of the 240 outlet. If a load is applied from the other leg the idler circuit won't see it and rev up the engine.

M.D.

 

[George2615]

I believe Steve is right. If the generator sees no load and idles down then a load such as a pump comes on there is that slight delay (a few seconds) that it takes to ramp up to full speed that the voltage and 60 cycles may not be correct which could cause harm to the pump or generator just like a brownout or low voltage condition from the power company.

My generator has an idle down position but it will only idle down when there is no load. If one light switch is turned on, the generator runs at full speed to maintain 60 cycles and the proper voltage. Of course at my house when running the gen there is always something plugged into an outlet that keeps it running full speed anyway. It never idles down when supplying the house with power.

 

[Travelover]

That idle feature is designed for use on construction sites where the generator may have no load for a long time, then a saw or drill is used and needs power. For a home, it pretty much needs to provide constant power, especially for high surge loads like a well pump or even a refrigerator.

Inverter type generators are a different story, as they provide full voltage at various engine speeds.

 

[BobRip]

My experience with power outage is that the refrigerators and freezers need to run at least 12 hours a day and this is about all I run the generator. Thus the idle back is of little use in my home power application.

Moss, well pumps are particularly difficult to start since the load of accelerating the water in the typically long pipes acts like a flywheel and can take many seconds (30 or so if my memory is correct) to get up to speed. The current stays pretty high during most of that period. I monitored this with an amp meter a few times and this is my interpretation of what I saw.

I have installed larger hydro tanks in my water system so I can typically go hours between running the pump. I actually have two tanks now, about 30 gallons each. This also extends the pump life during normal operation. Of course the times between runs depends on water usage. When we take showers, I leave the well breaker on and make sure the water heater breaker is off.

 

[Doc_Bob]

I have installed larger hydro tanks in my water system so I can typically go hours between running the pump. I actually have two tanks now, about 30 gallons each.

Who makes these tanks?
Bob

 

[BobRip]

I don't know, but they sell them at Lowes. Just get the biggest you can fit in your area. I have the two in series.

 

[SnowRidge]

I don't know, but they sell them at Lowes. Just get the biggest you can fit in your area. I have the two in series.

Bob, I assume you are talking about bladder pressure tanks. I also have two, but they are plumbed in parallel, not series. You can add more tanks by T-ing them into the supply line.

Sizing pressure tanks can get quite complicated. From what I have seen, they are frequently undersized, which can lead to early pump failure.