So this stuff is complicated. I have been reading this forum for the last few days, and have read a lot of the topics. I came up with this drawing to help me put this together and to hopefully have you guys point out any flaws. Cause you know I would hate to electrocute my wife. She totally wouldn't forget/forgive that.
So some questions to start. Outback inverters/chargers. Anybody using them here? What is your opinion on the brand or this specific inverter?
Does all of the AC grounds go to one ground bus bar? Even like the chassis grounds (generator, inverter)? Is that then grounded to the bus chassis?
How big of a fuse/circuit breaker between the inverter and the battery bank? Do I need one there? Or just a disconnect? I'm guessing I would need a 150A? 120V*30A AC RMS=3600/24V=150A DC.
I copied and pasted the Shore/Gen part from Outbacks installation sheet. Would I really be shorting the Neutral and Ground together?
Any other safety pieces that I am missing? Something you would change? Something out of whack with my calculations? Two pieces just really out of sync, size wise?
Magnum energy msh4024m, 4000w 24vdc hybrid pure sine inverter charger
MAGNUM ENERGY MSH4024M, 4000W 24VDC HYBRID PURE SINE INVERTER CHARGER
How do you handle 24V systems? How do you use the alternator as a charging source? How do you power 12V accessories? Is everyone just setup as a 12V systems?
Hey MM, that's quite the set up. going solar for me is on the horizon but not the near future. i believe there are charge controllers that you hook to the solar panels that have additional inputs for you alternator or generator.
the grounding questions you ask are pretty heavy. i can't give you a decent response. RV grounding is not a yes or no question. it needs to be understood, why and how.
the problem of rv grounding when using a generator vs a shore is that if you bond neutral and ground inside your rv for the generator, any plug into shore power would detect that as a fault and trip the shore line.
i don't understand 30A well enough to answer how to fix it. my system is 50a, different enough that i can't help.
24v would be nice. My setup is 12v. i don't know how you'd step down 24v to 12,(maybe a transformer) but there are lots of truck, bus accessories that run 24v, so the more of that you use, the more efficient it is.
the rest of your answers should be in the inverter manual.
magnum makes a great inverter/ charger. at 24 volt a 250 amp fuse would do. its best to go 12 volt for our application, just so much easier. you will need a charge controller between the panels and the batteries.
After doing some calculations we would use 2498WH per day for both the 12V & 120V applications. Then I multiplied the 120V applications by 1.15 to compensate for inversion loss to come up with 2793WH per day. A family of 5 can use some power! I estimated a little high, but I figure that is the way to go.
If I go with 4 T-105's that will get me about .9 days of power at 50% discharge. So I'm thinking I should go with 8 batteries to get 1.7 days. Then I could run the generator for 3-4 hours every day to top them back off without worry.
There won't be any solar, just shore and generator.
Questions:
1) Does anyone have a diagram how 8 - 6V batteries should be wired for 12V output? I can't find that exact diagram. I think I know how, but I want to know. Don't need to melt anything
2) What gauge wire should I be using to connect the batteries/inerter? The battery to inverter will only be 4 foot max.
3) Should I even try to connect the alternator with a disconnect? Or is this bank just too large and will kill my alternator?
Coachwork: Crown, integral. (With 2kW of tiltable solar)
Chassis: Crown Supercoach II (rear engine)
Engine: Detroit 6V92TAC, DDEC 2, Jake brake, Allison HT740
Rated Cap: 37,400 lbs GVWR
I'm using a borrowed computer in Mexico now and I can't open the PDF, so I can't see exactly what battery configuration you have. The only thing that confuses me is the link between the pos and neg. Isn't that going to just short out, or am I reading it wrong?
I'm using a borrowed computer in Mexico now and I can't open the PDF, so I can't see exactly what battery configuration you have. The only thing that confuses me is the link between the pos and neg. Isn't that going to just short out, or am I reading it wrong?
John
I think it will provide the series connection of two 6V battery banks for a total of 12V? Thoughts? It is a .jpg attachment on the last post.
that's a great link for battery info! i saw that a few days ago and have been pondering the balancing.
i think there is an error in both the last diagram from that link, and your copy in your diagram.
please, someone correct me if i'm wrong.
the text says that the current needs to travel through the same number of links and the same lengths of cable to balance.
in the final example, that is not demonstrated. the batteries closest to the load only go through one link, not two like the rest.
imo, you'd need to add two additional terminal posts. instead of all the wires ending at a common battery post, they all need to end at an additional terminal instead of the battery post. that way all batteries do travel through 2 links including the ones that only show current passing through 1 link as printed.
that's a great link for battery info! i saw that a few days ago and have been pondering the balancing.
i think there is an error in both the last diagram from that link, and your copy in your diagram.
please, someone correct me if i'm wrong.
the text says that the current needs to travel through the same number of links and the same lengths of cable to balance.
in the final example, that is not demonstrated. the batteries closest to the load only go through one link, not two like the rest.
imo, you'd need to add two additional terminal posts. instead of all the wires ending at a common battery post, they all need to end at an additional terminal instead of the battery post. that way all batteries do travel through 2 links including the ones that only show current passing through 1 link as printed.
I thought the same thing. In Method 4 he has some that are direct connected to the supply line and then others that have one extra hop. I may just go method 3 for simplicity in my mind. I was guessing that having only one extra hop made it okay?
the text says that the current needs to travel through the same number of links and the same lengths of cable to balance.
in the final example, that is not demonstrated. the batteries closest to the load only go through one link, not two like the rest.
Quote:
Originally Posted by MasterMerck
I thought the same thing. In Method 4 he has some that are direct connected to the supply line and then others that have one extra hop. I may just go method 3 for simplicity in my mind. I was guessing that having only one extra hop made it okay?
Now you two have me puzzled. When I look at SmartGauge's Method 4, I find the path from the negative output lead through the battery maze over to the positive lead.
When going through the bottom battery, the path is down through one short link on the right, then across the battery, then up a long link on the left. Now we're at the other output lead.
Going through the 2nd battery the path has no links on the right, then across the battery, then down one short link on the left, then up one long link on the left, and to the output.
Same deal for the 3rd and 4th batteries: in all cases the path involves one short link and one long link. The short links carry the current of just one battery and the long links carry the current of two batteries, so voltage drops across the wires works out. (voltage drop in the wires carrying varying number of batteries' currents is the thing I had failed to notice when I was introduced to method 2 a few years ago).
the 2 pairs are both balanced, but i was having trouble seeing the balance in between the 2 pairs. now i see, three wires on the upper pair, and 3 wires on the lower pair - balancing the balanced pairs out.
Two more quick notes: first, please remove the ground-neutral bond "neutral on input connected to ground." One should not tie those together when using shore power because the shore power system already provides the connection (and it should exist in only one place in the shore power system).
The ground-neutral bond should be provided, though, when running on inverter or generator power. Hopefully Magnum's support people can provide advice on how this is to be done. It's tricky with the hybrid inverter because one might run the inverter alone (bond needs to be provided), both the inverter and a generator (bond needs to be provided), or inverter and shore power (bond should not be provided).
You might consider installing a relay powered by the shore power input. The relay's normally closed connection could be used to provide the ground-neutral bond; when shore power is connected the relay would open and remove the bond. When using a generator, configure the generator to provide the bond.
Second note: more like unsolicited product recommendation. Just a couple weeks ago I built new battery cables for my pickup truck. I got 4/0 SGT type cable from a local supplier, plated closed-end lugs from Amazon, a relatively affordable 12 ton hydraulic crimper on eBay, and adhesive-lined heat shrink tube from Mouser Electronics. It all came together really nicely, and with the closed lugs and adhesive shrink tube it'll be a long time before I have to worry about corrosion eating its way up my cables! I'm looking forward to using all this again for repairing the starter cables on the bus and building new house battery cables.
the battery charger has never worked this well before! rarely did i go over 90% charged. the only time i've seen it this high is when i put the car charger on the battery bank.
i ran the fridge over night to tax the system a bit, and woke up to this.