I've learned that my inverter will either charge or invert, but not both at the same time. The problem is, when I plug into a simple 15 amp extension cord, I don't have enough power to recharge and run anything in the bus.
So, I got this wild idea. What if I run my power off the inverter and have much of what I need, and plug in only a 24V charger to maintain the batteries? The inverter will absorb the short term higher loads ie: coffee pot, or water heater, etc. The charger will bring the batteries back from the heavier loads.
Am I out to lunch? Will this work? Will there be any conflict?
Thanks
this one is amazing but big bucks !
if you only have 15 amps to plug into it will add more power if needed from your battery bank then as soon as there is power available from your 15 amp post plug it will recharge the batteries . again and again . I have used my a/c this way and was shocked how often it was recharging the batteries well the a/c was on
https://www.solarwholesaler.ca/product/magnum-msh4024m-24v-hybrid-invertercharger/ (https://www.solarwholesaler.ca/product/magnum-msh4024m-24v-hybrid-invertercharger/)
dave
Quotethis one is amazing but big bucks !
if you only have 15 amps to plug into it will add more power if needed from your battery bank then as soon as there is power available from your 15 amp post plug it will recharge the batteries . again and again . I have used my a/c this way and was shocked how often it was recharging the batteries well the a/c was on
Yup, I know there's some pretty awesome technology out there, but I'm just a poor man working my way through life. I like my inverter and I don't want to buy another.
But in my little brain, another charger seems appropriate.
Something like this perhaps?
https://www.batterystuff.com/power-supplies/load-bearing-chargers/power-max/power-max-pm3-30-24.html (https://www.batterystuff.com/power-supplies/load-bearing-chargers/power-max/power-max-pm3-30-24.html)
You can still only do so much with a 15 amp cord, there is no free lunch.>>>Dan
Quote from: Tikvah on September 04, 2016, 06:45:36 AM
Something like this perhaps?
https://www.batterystuff.com/power-supplies/load-bearing-chargers/power-max/power-max-pm3-30-24.html (https://www.batterystuff.com/power-supplies/load-bearing-chargers/power-max/power-max-pm3-30-24.html)
One thing to be aware of with the Iota and Power-Max chargers - they have very high starting surges, and their Power Factor is also quite low (about 0.6-something if I recall for the Iotas). This means they could trip breakers when first switched on; their low PF isn't of concern unless you're powering them offgrid from a generator. The alternative to a low PF charger is one like the Mean Well (what a name!) that has a PF in the high-0.9s, but because it's a multi-stage "smart charger" it won't charge batteries if there's any load on them at the same time - that doesn't sound too smart to me.
Do your research first - chargers aren't as simple as they seem!
John
Since chargers and inverters often have their own quirks, what might seem like a good idea might not work out the way you want it to. If you have a particular charger in mind, maybe you could speak to someone in their tech support department to get their blessings. Same goes for the inverter.
QuoteSince chargers and inverters often have their own quirks, what might seem like a good idea might not work out the way you want it to. If you have a particular charger in mind, maybe you could speak to someone in their tech support department to get their blessings. Same goes for the inverter.
Ya, that's a good idea. For example, I never thought of the fact that some chargers don't charge if there is a load. That's specifically why I want it - so it charges during a load.
I can run everything in my bus except the AC and charge my batteries at their normal rate with a 15 amp circuit. I think you are trying to fix something that isn't broken. With most smart inverters you can adjust the charging current, and therefore the current draw on the 15 amp circuit. Modern smart battery chargers don't really draw all that much current once the initial inrush of bulk charge is done.
Hey Dave, what kind of inverter do you have?
I agree with bevans, a modern "smart" inverter/charger would have a max current setting that controls how much it is allowed to draw from the incoming shore AC (whether from mains or gen).
If I understand your proposed solution, you'd essentially be robbing from Peter to pay Paul anyway, since your storage pool (your batteries) is the same and your input feed source is also the same (15amp input). So unless you plugged your charger into a different 15 amp circuit, you'd risk blowing your single circuit. Plus, regardless, if the standalone charger ever detected a draw (i.e. a significant enough voltage drop that exceeds its output capacity to compensate), it will likely shut down. That would mean that your battery bank doesn't have the capacity to handle that current load and is trying to use the charger as a DC source.
Your inverter should be smart enough to invert (i.e. Draw from batteries) when load requires it (augmenting input AC with inverted DC from batts), and when load settles down and normalizes, it should cease being an inverter and return to being a charger (as max input current allows). Thus indeed never really inverting and charging at the same time.
This is the way Victron and Magnum (among others) do it.
This is what I have: http://www.theinverterstore.com/3000-watt-pure-sine-inverter-charger-24-volt.html (http://www.theinverterstore.com/3000-watt-pure-sine-inverter-charger-24-volt.html)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fep.yimg.com%2Fay%2Fyhst-81669383275414%2F3000-watt-pure-sine-inverter-charger-24-volt-58.gif&hash=e8dce9e050b5c24d6098a65f4a6543b37bab95c3)
3000W 24V
Quote from: Geom on September 05, 2016, 09:22:03 AM... Your inverter should be smart enough to invert (i.e. Draw from batteries) when load requires it (augmenting input AC with inverted DC from batts), and when load settles down and normalizes, it should cease being an inverter and return to being a charger (as max input current allows). Thus indeed never really inverting and charging at the same time.
This is the way Victron and Magnum (among others) do it.
Some sources call that "load sharing". An Outback (at least some Outbacks) don't do that. If you exceed the max set on your shore cable, it will shut down draw on the shore power and pull *all* the juice to invert your loads from the batteries. Then, when your loads drop below the max, it will go back to using some shore power to run your loads and use the rest for recharging the batteries. It's probably not a big difference, but it seems to me that it's less sophisticated and will draw batteries deeper and more often than the load share system.
I didn't know enough to ask the right question when I bought the Outback. :(
load sharing yes . as the a/c cycles and the compressor turns off and on that is when the inverter starts charging but if the a/c cant keep up then yes it would be shared with the batteries . the system works great as you will never blow a breaker ( 15 amp ac ) now if you are a POWER HOG and can,t control the amount of power you use then 15 amps will never work . a little trick I do when I only have 15 or 20 amps available is if you want to turn something else on when the a/c is on just turn up the setting on the thermostat for the a/c then when you can turn off the other item ( say a toaster ) you can turn the a/c down again to cool off with out tripping the breaker . works great
dave
forgot to add there are settings that you can use to set the ac amperage that you have say 15 amp ,20 amp 30 amp that is how the inverter knows when to use the battery bank to add to the system + if you set the incoming ac amps on the display you can see how much amps you are using at any time
sorry for the drift
dave
Load sharing will simply switch between inverter power or shore power as the ac load requires. Hybrid inverter will supplement shore power by adding inverter power to it as necessary, combining both sources of power together. Load sharing inverter only provides one or the other source of power, not both at the same time. Important to know the difference if you're shopping so you know you get what you expect it to do.
Sent from my SM-G920T using Tapatalk
I read the (rather thin :) ) manual for that inverter. It's actually a pretty nice straight forward inverter.
But it does not have a rate limiter to control its input load.
It does have the ability to limit the charge current (and thus the required load) via dip switches.
But that's not something you really want to do, as that would limit your ability to charge when you are hooked up to a high amperage plug (30 or 50 amp).
This inverter also does not really "power assist" the load per say. It more tolerates a rather high initial surge current (likely by augmenting some from batteries). But it only does so for up to 20 seconds.
It has a setting that can control AC preference vs DC preference. I would definitely check that to make sure that it's in AC preference. In DC preference it's essentially always inverting, and only uses AC when the batteries are depleted.
I can't quite figure out WHY you'd want that, but they rambled on about some technobableygook about doing so in a solar configuration. And I guess I can kinda sorta maybe see that, but even then I'd still prefer to use shore power when it's available; EVEN WITH solar backing it.
So from what I see, without a rate limiter I'm not sure how you're not blowing breakers already.
From what I read, that inverter runs as if the taps are fully wide open. And that transfer switch will handle up to 40 amps.
So I'm curious why/how you're noticing that undesirable behavior; as it has no idea it's on a 15 amp, vs 30 amp , vs 50 amp circuit.
I'm also not sure why, when the load drops (say after the coffee is made), that it wouldn't just go back to charging as normal.
So I would definitely check the dip-switch that controls that AC vs DC preference.
Now a possible solution could be intentionally setting that dip-switch to DC preference (yeah yeah, I know what I said above :) )
If you did so, then you'd constantly be inverting. But then you could just hook a plain old 24V charger to whatever input AC plug you have available and have that charge the batts all the time. And since you'd be running off batts all the time, the inverter wouldn't really know the difference. That's not really an ideal solution as it limits your load potential to just the 3000 watts of the inverter, you wouldn't be using the rather impressive high-efficiency charger already on the inverter, and you could possibly overload that external charger if the load is high enough (as previously mentioned). But I think it'd get you (close to) what you need.
But again, there should be no reason to do that, as the inverter should just go back to charging when the load subsides.
Confusing enough??? :D
Quote from: Geom on September 06, 2016, 08:35:54 PM... I read the (rather thin :) ) manual for that inverter. It's actually a pretty nice straight forward inverter. ...
Confused .. ??? ??? Which inverter?
Quote from: Tikvah on September 05, 2016, 09:49:05 AM
This is what I have: http://www.theinverterstore.com/3000-watt-pure-sine-inverter-charger-24-volt.html (http://www.theinverterstore.com/3000-watt-pure-sine-inverter-charger-24-volt.html)
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fep.yimg.com%2Fay%2Fyhst-81669383275414%2F3000-watt-pure-sine-inverter-charger-24-volt-58.gif&hash=e8dce9e050b5c24d6098a65f4a6543b37bab95c3)
3000W 24V
The OP's inverter is what I was referring to :D
Quote from: Geom on September 07, 2016, 08:52:34 AMThe OP's inverter is what I was referring to :D
Got it, thanks!
That's helpful information Geom,
I haven't understood the AC priorioity vs the Battery priority switch.
I think I need to find about a 30 amp, 24 volt charger that will charge even when there is a load.
Thanks
Quote from: Tikvah on September 07, 2016, 12:01:44 PMThat's helpful information Geom, I haven't understood the AC priorioity vs the Battery priority switch.
I think I need to find about a 30 amp, 24 volt charger that will charge even when there is a load.
Thanks
Hey, Dave. As you may have noticed from my comments on this and other threads about inverters, I haven't been thrilled with the Outback that was recommended to me a while ago. It pretty much works but I'm tired of lots of sorta clunky things in its operation -- plus, it's 12V and the big alternator on my new engine (and most of the engine control system) is 24V and it's easier to find a heftier inverter with 120V output if it's 24V input. So, I've been looking.
I have become convinced that -- like a lot of things in life -- you don't get what you don't pay for and you've got to watch people who want to not give you what you did pay for. It appears to me that performance, features, ease of use, and reliability are pretty much directly linked to $$$$. There are lots of cheaper inverters out there but their specs don't look good and reviews on Amazon and other places on the net seem to indicate that few of them make people happy. Chris and Cherie (the Technomads) are really big on their Victron; I sure like the way it works, highly efficient, easy to use, good selection, models specifically for "mobile" use that actually have things we need and not just a little weather resistance. Whoever designs Victron inverters really knows what people need. The control system looks really well featured and easy to use. But there's the thing about the $$$. Oh, well, I guess those are the choices. I have a while before I want to buy -- if you find something that looks good, let us know, OK?
Thanks, BH