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Re: The Official unofficial CPE 2000i Generator Thread
Rygar wrote: Okay, now that raises another question. What's the difference between a generator and an inverter? Sorry, but the two answers already provided to this question were both a little off. An alternator produces alternating current. In a "syncronous generator", the AC from the alternator is regulated at high voltage, and the frequency is controlled by governing the rpm of the coupled engine/alternator. This high voltage AC is fed directly to the generator's receptacles. In an "inverter generator", the AC from the alternator is regulated at low voltage, then fed through a rectifier to produce low voltage DC. That low voltage DC is then fed through an inverter which produces high voltage AC. That's the difference. Think of an inverter generator as an automotive electrical system plus an inverter, but without the battery. This is why some inverter generators also have a 12v DC receptacle - they just tap the low voktage DC before it goes into the inverter. It's inefficient to go from AC to DC and then back to AC, but by doing it this way, the frequency of the AC is decoupled from the rpm of the engine/alternator. This allows the throttle to be be controlled by a stepper motor instead of a governor, and the rpm can be reduced when there is less load, saving fuel. Because of the inefficiency of the AC-DC-AC conversion, syncronous generators are slightly more efficient than inverter generators at full load (and a lot cheaper to build). What makes the inverter generator even worth the bother and expense, is the fact that most portable generators almost never operate at full load.949Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
otrfun wrote: Curious, when does inrush current become surge current? After 10ms, 100ms, 500ms, 1 second, 1 minute?? Technically, what we're talking about here is in-rush current, sometimes called input surge current or switch-on surge current. http://en.wikipedia.org/wiki/Inrush_current An electrical surge is a different phenomenon, where the supply voltage rises or spikes. So, to answer your question: In-rush does not become surge. (Well, technically, I think there is a way to use in-rush to induce harmonic frequency bouncing and cause a supply voltage spike or surge, but that ain't happening here. :) ) What the generator marketing departments call "surge" actually means, "temporary overload". A Honda running for 30 minutes at 2000w is not handling an inrush - it's just running on overload.472Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
mfifield01 wrote: I ran it connected directly to the camper power cord (25' 10g) and it still bogged down. I checked voltage drop on the long run and had 123.x volts on a wall plug in the camper. I used 10, 12, and 14 gauge wires to get to that distance. A reminder... Voltage drop is a function of load. As the load on the circuit increases and decreases, so does the voltage drop. So measuring the voltage of a 400' loop of copper isn't really going to tell you anything if there is no load on it, since 0 load = 0 voltage drop. (Or, not much anyway, there will be a touch due to the wire itself, but at 120v it won't be much and might not even be noticeable.) To find out what's really going on, one has to measure the voltage of the loop while it's under full load in order to induce the maximum voltage drop.574Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
professor95 wrote: You can do this with your eyes, touching the battery case and a cheap voltmeter. You absolutely do not have to invest in a "smart" auxiliary battery charger for generator use if you are willing to follow a few "smart" rules. Well, that also depends on the battery resistance and how much amperage the power supply actually causes to flow through the battery. Too little amperage flow equates to a lot longer generator run time. But this reminds me of something else - Morningstar, for one, allows their solar charge controllers to be bench tested by feeding the output of a regulated power supply into the input of the charge controller. So, that's one alternative - in the case of the previously mentioned power supply, set it to 15.5v and run it through a solar charge controller to get a proper multi-stage charge into the battery.386Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
Glenlivet wrote: If he can use that to safely activate his new battery, and doing so costs him .0025% of his battery's full capacity in so doing due to a bit of sulfation, then it's cheap at the price, especially when compared to what the donkey at the parts desk might have done! Well yes, but the problem with sulfation is that it's additive. Each time the battery is drained and not fully recharged in a timely fashion, a bit more of the lead in the plates get covered with crystalline sulfation. So the battery just keeps losing total capacity little by little over time. Eventually, that 100ah battery might actually be a 50ah battery, or a 20ah battery... As long as the crystals haven't built up to the point of shorting the plates, or the battery hasn't been overheated causing the plates to warp and touch, the battery will behave normally. I.e., it can be charged up and will have a resting voltage of 12.8v, etc. It'll just go dead a lot faster because its total capacity has gone down. Sulfation forms any time a lead-acid battery is drained. That's normal. And it dissolves back into the electrolyte when the battery is charged. That's normal too. The problem is when it sits long enough to harden. Then it doesn't dissolve when the battery is charged. It has become permanent. Until makers start supplying their AGM batteries already activated, like Odyssey and Optima do, the chance that someone out of your sight will like as not activate and charge your nice new AGM battery the same way Grandpa charged the six volt Exide battery in his DeSoto and wreck it, is just too great. Most AGM batteries are VRLA (valve-regulated lead-acid), in other words - sealed. They are shipped fully charged from the factory, minus whatever self-discharge from sitting on the shelf at the dealer (not a lot, AGMs don't usually self-discharge very quickly). So with most AGMs there is nothing for a dealer to do, except perhaps give them a top up charge if they've been sitting a while. Since they are factory sealed, there is no "activation". And yes, apologies to all for the hijack. I just felt I should speak up about using a regulated power supply as a battery charger before someone ends up deep sixing an expensive battery.311Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
Glenlivet wrote: Seeing as a common vehicle operating voltage is 13.8 V., are you saying that a production car's battery, as designed, never achieves a full state of charge? Yes, that's what I'm saying. (Though my old '76 Ford campervan bus voltage averages closer to 14v.) Voltage regulated alternators (~constant voltage charging systems) aren't really designed to charge batteries at all. They are designed to supply and maintain a more or less steady bus voltage, while supplying whatever loads happen to be drawing down the bus. The typical cranking battery won't be discharged much by starting the vehicle. Say 250a starter draw for 3 seconds. Ignoring Peukert for the moment: 250 amps x 1 hour would be 250 amps per hour or 250ah 250ah / 60 minutes would be 4.1 amp*hours per minute 4.1ah / 60 seconds would be .07ah per second .07ah * 3 seconds would be .21ah So the cranking battery, on average, could be expected to be drawn down by one fifth of an amp*hour each time it was used. The voltage regulated alternator system is designed to hold the bus voltage, and by doing that, can be expected to replenish the teeny-tiny amount of amperage drawn from the cranking battery. But, that battery will be overcharged if held at too high a voltage for too long, so it's better to hold the bus voltage down to a level which will not cause damage to the battery over a long exposure time. That would seem awfully inefficient and would represent awfully negligent design from decades of automotive engineers. :h I disagree. It would be only slightly inefficient, and would represent a design philosophy of "best compromise" by the engineers. The design engineers do have better solutions - such as multi-stage voltage regulators often used in marine applications. You don't often find those used in automotive applications however. There are also alternator/voltage regulator systems for automotive applications which utilize PWM technology - though even they are still simply single-stage constant voltage systems designed to maintain bus voltage. The PWM allows for a much tighter, more well-regulated bus voltage - but really does nothing to improve battery charging, which is proper, since the voltage regulated alternator is not designed to be a battery charger in the first place. The internet is chock with advice and information about battery charging, with most lore being similar but variations existing. The most telling phrase I encountered is: 'You talk to different engineers, even at the same company, you get different answers.' :B Not surprising, of course, because there is a reason why it happens: If you study the recommended charging specs for a large assortment of lead-acid batteries from a large assortment of manufacturers, you will find mostly similar trends, but each with their own specific minor variations. This is largely due to the fact that a lead-acid battery is a big sloppy chemical device and not a precise electronic component. Basically, it's the St. Bernard of the electronics world. For the most part, "close enough is good enough" when dealing with such a sloppy and imprecise apparatus. I'd have to think that the finished and stabilized voltage of an out of circuit wet battery will dictate what the level of charge it containes, and when the full charge voltage is 12.7 and the battery, removed by several hours from a charger, reads 12.7 volts then it is 100% charged, whether it got that way from being on the vehicles' own charging stystem, from being 12 hours on a 'maintainer' that generates no more than 13.8 volts, or whether it got that way from being on a three stage charger for a shorter period of time. It would seem so. However that doesn't exactly agree with the manufactures recommended charging routines, which generally (and pretty much always in the case of deep cycle), specify an extended time at a higher voltage (absorb stage) to achieve full charge. Personally, I agree with you: Hold a battery at a low float voltage for long enough (in some cases, a few days) and it will eventually reach a full charge. (An analogy would be simmering a sauce at a very low heat as opposed to simmering at medium heat.) But then...by not pumping it up to a full charge quickly, sulfation certainly will result, and what started as a 100ah battery might only be a 99.75ah battery at that point. But yes, it will be filled...to the limit of its new lower capacity.311Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
The problem with those power supplies as battery chargers, is they are regulated to 13.8v. That is less voltage than what almost any flooded or AGM battery manufacturer recommends to achieve a full charge on their batteries. Most 3-stage chargers will do a bulk to 14.4v to 14.8v (depending on who made the charger) and then drop to 14.2v for some hours for the absorb stage, and then drop to 13.2v to 13.8v (again, depending on who made the charger) as the long-term float (maintenance) stage. So even if the power supply puts out 36a (peak, this would drop off as the battery voltage rises toward 13.8v), it's not going to get the battery fully charged because it will never push the voltage high enough to fully activate the chemistry (never reach full absorption). It will work to get the battery to 85% or so of a full charge, and will hold it there as long as there is less than 36a of loads on the battery. But taking the battery to 85% instead of 100% will increase the rate of sulfation, and will not extend the life of the battery as much as it would be extended if the battery were regularly pumped up to 100% with a proper charger.312Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
The issue with rigging gravity feed from one tank to another is the risk of overflowing the lower tank. If it were me, I'd probably T into the fuel line and run a separate line to the external tank with a valve to switch between the internal and external tanks. BTW FYI: In discussing with Champion tech support the problem that my generator had, I was told that the warranty doesn't cover "off grid" usage. I asked for clarification and was told that RV use IS considered "off grid".368Views0likes0CommentsRe: The Official unofficial CPE 2000i Generator Thread
Atlee wrote: Is there larger extended run gasoline tank available that will work on twin Champion 2000 generators? I know there is a Honda one available. For that matter, would the Honda extended run gas tank fit the Champion 2000? The reason that extended run tanks work on the Honda, is because it has a fuel pump. So you run a line into the top of the fuel cap from an external tank, and the vacuum created by the fuel pump sucks fuel in from the external tank. Setting up an external tank for a generator which uses gravity feed is a whole other ball game.368Views0likes0Comments
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