After receiving great feedback, we've updated our electrical plan. We're going with a 24v system and will tie in to the alternator for charging. Before we draw up a schematic, we'd very much appreciate the Board's scrutiny of the revised plan. Please fire away...
(https://lh5.googleusercontent.com/-CPKWZJmkrD8/T6Q5iFM8yzI/AAAAAAAAAJU/TLYbzPA7ZWo/s800/Electrical%2520Schematic%252003.jpg)
water pumps more common in 12 volt--I use 12 volt led (rite or wrong) You can get replacement about everywhere in 12 volt.
Ridiculous.
Just remember to balance your electrical load in your shore-power box between legs. example one ac on one side and other opposite. That way when you transfer your gen set in your load will be balanced. Look and see how you contact in you box is laid out. this might be as simple as putting them one under another or might require a total separation.
Unlike Geoff, I will provide some constructive commentary. Geoff has made it quite clear he prefers 12 volt over 24 volt.
I think you're overly complicating things with the extra transfer switches and all that. The MS4024 has a transfer switch that will handle two legs at 30 amps each. Your diagram seems a little unclear as you've connected 115 volts and 24 volts together in some places from what I can tell. The Honda EU6500is is a nice generator, but it is designed to sit outside, not enclosed and not run while on the road. (Maybe you aren't going to run the generator on the road with the 50DN.) Hauling gas for a generator can be a pain compared to a diesel model.
I would suggest you go to some of the web sites that sell inverters and down load some manuals for them. This will tell you how to wire up your system. Most of your diagram seems way off. You won't need any transfer switch at all if you buy some inverters. It isn't that complicated. Trace and Xantrex are just a couple names. Some of your diagram looks wrong, but we haven't done solar panels. All dc should run through your batteries. You might want to ask what everyone thinks of solar.
Don and Cary
1973 05 Eagle
GM 4107
Neoplan AN340
Quote from: robertglines1 on May 04, 2012, 05:57:49 PM
Just remember to balance your electrical load in your shore-power box between legs.
When there is 240VAC/50Amp shore service available, is there
also 120VAC/30Amp available? Or is it an either/or proposition?
when there is 50 amp on post there is 30 amp and usually a 20 amp plug also 30 amp at almost all campgrounds. 50 amp getting at most(80%) so your good to go. My comment about the 12 volt pump was intended to say if it quits you could go to any rv dealer and get one off shelf. I have not found that to be true with 24volt. Bob
Quote from: Cary and Don on May 04, 2012, 06:33:11 PM
I would suggest you go to some of the web sites that sell inverters and down load some manuals for them. This will tell you how to wire up your system.
Great advice. I just did that for the MS4024, and it confirmed most of my plan. It also recommended a bypass switch to cut the inverter out of the equation, which I just added after reading that.
Mid,
Welcome aboard. I have followed your beginnings but not responded to them yet. I think you are off to a great start. The more you can plan out, the better. Good for you.
I completely agree with the 24v thing. That makes a lot of sense. Our electrical system is made up of a 20KW Kubota genset, 2 4000 watt Trace inverters, 6 8D deep cycle batteries, all 120V in the cabin, 24V water pump. You will do just fine with the 24v. No worries.
One minor comment that I might have, but then again maybe not. You might want to simplify your system just a tad. The subpanels might not be totally needed, depending on what you are using. We have two small (100 amp each, so not too small) panels that we use for all of our AC. One before the inverters for when we are on shore power. The other is after the inverters and everything else in the cabin. Like I said, though, if you are using smaller panels, it might make sense to locate them different places.
I do agree on the transfer switches. Might not need all of them.
Your forsight and planning is impressive. Good work. I look forward to seeing the build.
God bless,
John
Quote from: John316 on May 04, 2012, 07:26:52 PM
I think you are off to a great start. The more you can plan out, the better. Good for you.
Quote from: John316 on May 04, 2012, 07:26:52 PM
I do agree on the transfer switches. Might not need all of them.
John
John,
Thanks for your positive yet critical feedback. I'll look more at what I'm trying to accomplish with the switches and see if I can figure out a simpler way of going about it.
-Mike
My god! You people are fantastic....you are the only people here that are more Percice and anal than the master of Percice,Sean welsh..who can write 4pages on how to change your socks properly .your plans are 2nd to none! Keep up the good work! You are going to have a bueatifal bus.
other than a tad overcomplicated, they do make 3 way transfer switches... just saying...
i use 12v system only and with inverter am going to install a 3 way transfer switch...
A couple of things strike me about the solar panel arrangement - neither are criticisms, merely questions:
- Is there any real purpose for the direct link between the charge controller and the 24v sub panel? I cannot really imagine a scenario where you'd want to isolate the battery and try to run the DC side of the bus directly off the solar panels
- You've got a 24v charge controller, which is logical for a 24v system. But in my limited experience solar panels come in two varieties - either those for domestic 'grid tie' use, or those for recreational use on boats and motorhomes etc - of the latter type, all the ones I've seen have been aimed at 12v systems. I found a tech-spec of the 'Astroenergy 290w' panel mentioned in your diagram (http://www.astronergy.com/attch/product/CHSM6612M.pdf (http://www.astronergy.com/attch/product/CHSM6612M.pdf)), and these have an open circuit output of 45v and an under-load output of 32v. I'm curious to know whether these outputs are correct for feeding into a 24v charge controller - I'm not suggesting that there's any chance of damaging it, simply wondering whether, with those panels, you'll be spending good money for solar panel capacity which you'd then be wasting.
Jeremy
(My bus will also be entirely 24v by the way).
I forgot to mention the water pump. I use the Flojet Sensor VSD. It can run on either 12 volt or 24 volt. This pump is fairly common and I know Camping World carries it. Many RV dealers probably carry it too.
Guys: I stand corrected on 24volt water pump. My new lesson for today! As I don't build to be off grid except on rare occasion I used what was common supply around me. What little I'm off I use the gen set. For me the math isn't there . I do understand your needs and desires to be independent off grid for long periods. Nice about our hobby-----do it your way. I stand corrected. Bob
My pump is a Flopump (different to Flojet I think), and I didn't have any trouble finding a 24v version.
I've bought almost everything for my bus from Ebay, and take the approach of starting to look for the things I need long before I need them - which is easy on a project which take as long as ours do. With the exception of my big Heart inverter, I think everything I've bought so far has been new, and without exception, everything has been very cheap - because I'm in no hurry and can wait for the right opportunity to come along. The purpose of me saying this is that, in my experience, 24v stuff is invariably much cheaper than 12v - simply because there is much less demand for 24v stuff on Ebay, and, if you can be bothered to look for them, those '99p start, no bids, ending-at-2am' auctions are just there for the taking.
Jeremy
I knew there was something I liked about you Jeremy ;D I walked out of Dana Marine Flea Market, with a refurbished 24V Macerator and water pump for about $60 for the pair.
I got several brand new 24V items off Ebay for dimes on the dollar. For the avg person 24V is exotic and scarry. So they go with what they know. Even my inverter was brand new.
I did not have lots of storage so I had to be careful about what I bought in advance. JIm
Quote from: belfert on May 04, 2012, 06:24:14 PM
Your diagram seems a little unclear as you've connected 115 volts and 24 volts together in some places from what I can tell.
Damit. I wanted to dismiss your post b/c I'd never make an idiot mistake like that. But after a third look, I have the alternator going into the ac input on the inverter. :o
Redoing it with a Xantrex Pathfinder now.
Hi Mike,
WOW! Where did you get a Magnum MS4024 inverter for $1750? I just ordered one from Northern Arizona Wind & Sun yesterday for $2000 including free remote control and free shipping for the inverter. I had to pay shipping for the remote and the battery monitor that I also ordered.
Looking at your latest electrical plan I see a few things that I would do differently. I would eliminate the two A/C sub panels and the transfer switch feeding them. I would connect the sub panel you show after the inverter to the transfer switch that selects between the shore cord and generator. Then there are a couple of options: 1. Put one breaker in for the A/C that you only want to power from the shore cord or generator and one double pole breaker to the inverter. Then from the inverter to the main sub panel with the other A/C breaker and all your other 120 VAC breakers. 2. Put one A/C breaker and breakers for any loads you don't want to power by the inverter in the sub panel supplied from the shore cord/generator transfer switch. Then from a double pole breaker feed the inverter and from the inverter feed the sub panel that powers everything you want the inverter to power without shore/generator available.
You will probably want to put a 250 amp fuse and shunt for your Trimetric in the cable between the battery bank and inverter along with the disconnect you you show. You may already know this so forgive me if I am being redundant.
Good luck, Sam
Quote from: Midwilshire on May 05, 2012, 07:28:35 AM
Quote from: belfert on May 04, 2012, 06:24:14 PM
Your diagram seems a little unclear as you've connected 115 volts and 24 volts together in some places from what I can tell.
Damit. I wanted to dismiss your post b/c I'd never make an idiot mistake like that. But after a third look, I have the alternator going into the ac input on the inverter. :o
You also have a connection between the pilot controlled contactor and 110 volt. Since the contactor is controlling the 24 volt from the alternator I have no idea why that would connect to 110 volt at all. The connection from your alternator should go straight to your battery bank, but I think you figured that out.
I would suggest different colors for different voltage on the diagram. It would help makes things clearer if you post a revised diagram for review.
Looking at the origional diagram, you are going to have more excitement than you want.
Take a close look at the connection between the AC generator and the DC Alternator thru the manual control switch, (I see much excitment, not to mention fire and cost)
Of course I might be over looking something here, but as is, it is very scarey, WOW :o :o
Normal setup would be to tie the DC alternator into a battery bank of some sort, not the AC side.
There are other issues, but this one is a major concern.
What am I missing ?
Dave
Quote from: wg4t50 on May 05, 2012, 02:20:33 PM
What am I missing ?
You're evidently missing the posts just prior to yours, where that point was being discussed
Jeremy
The best thing he did was put it out here before building. it ! A learning curve is difficult if done by trial and error. I think we all agree on that. He is a brave man and wise. My hat off to him. Really ambitious for first build. The board wasn't around for my first! Best wishes...... Bob
Quote from: Sam 4106 on May 05, 2012, 01:32:03 PM
WOW! Where did you get a Magnum MS4024 inverter for $1750? I just ordered one from Northern Arizona Wind & Sun yesterday for $2000 including free remote control and free shipping for the inverter. I had to pay shipping for the remote and the battery monitor that I also ordered.
I'm ready to pull the trigger on this tomorrow, unless a BusNut tells me not to:
http://offer.ebay.com/ws/eBayISAPI.dll?BinConfirm&_trksid=p4340.l1356&rev=2&item=310395352617&fromPage=4340&quantity=1&fb=1 (http://offer.ebay.com/ws/eBayISAPI.dll?BinConfirm&_trksid=p4340.l1356&rev=2&item=310395352617&fromPage=4340&quantity=1&fb=1)
-Mike
Quote from: robertglines1 on May 05, 2012, 03:27:29 PM
A learning curve is difficult if done by trial and error. I think we all agree on that.
Thanks Bob!
And speaking of that trial and error (particularly the error part), we'll post a video of our plywood and fiberglass
sieve holding tank when my ego recovers and when Gigi's done editing out the profanity.
That Magnum is the unit I would go with. That is the unit I was going to buy when I thought I needed a new inverter. I suggest using this link instead if anyone wants to look at the Ebay listing: http://www.ebay.com/itm/310395352617 (http://www.ebay.com/itm/310395352617) The link provided goes to the purchase page for the inverter.
I would suggest contacting Inverter Service Center by phone to see what price they will give you. www.inverterservicecenter.com (http://www.inverterservicecenter.com) I had contacted them for service for my Prosine 3.0 and they told me Xantrex doesn't provide any way for service centers to fix the Prosine. They gave me a really good price for the Magnum that was better than their website. (My buddy managed to fix the transfer relay on my Prosine 3.0 and it still works today.)
Quote from: belfert on May 05, 2012, 01:53:40 PM
I would suggest different colors for different voltage on the diagram. It would help makes things clearer if you post a revised diagram for review.
How's this, Brian?
"Known Unknowns"(https://lh5.googleusercontent.com/-TFCYu4c1FGU/T6XbWb3uAXI/AAAAAAAAAJs/BdLEUGSvlv4/s800/Electrical%2520-%25206.jpg)
Seems I'm getting closer and learning a lot from the archives and your feedback, which sends me back into the archives and google.
One thing I've learned is that I'm confused -- after hours of reading and trying -- about the alternating current system.
Here's what I'm trying to do:
- 1. Give AC priority to shore power over generator when available.
- 2. When on 240 shore power, run one air conditioner off one leg, and
run the inverter (and 2d air con) off the other leg – in order to load
balance. Or is there a better way with an isolation transformer?
- 3. When on 120 shore power, run one air conditioner and the inverter
through it, and run the other air conditioner through the generator.
- 4. When not on shore power, run all air conditioner loads through the
generator, unless alternator power is available, in which case, run
forward air conditioner through inverter.
- 5. Combine alternator and solar panels when available, or at least give
priority to the alternator.
- 6. Not put my family or our bus at risk of harm.
As always, I appreciate your time and feedback.
-Mike
Most transfer switches unless you build your own will give priority to the generator by default. Why would you run the generator if you have shore power?
Where will you be staying in Minnesota?
Quote from: belfert on May 05, 2012, 07:48:43 PM
Most transfer switches unless you build your own will give priority to the generator by default. Why would you run the generator if you have shore power?
I agree. I want to use shore power only, and use the generator only if shore is not available or not enough.
Quote from: belfert on May 05, 2012, 07:48:43 PM
Where will you be staying in Minnesota?
Family farm in Lakeville. Not far from Minneapolis....
Hi Mike,
I too applaud your research. For me, part of the enjoyment I get form working on the bus is the learning experience.
Yesterday I offered some bad advice in my post. I just learned that the Magnum MS 4024 has a 30 amp transfer switch in it so option 1 is not viable. If you used that option you would not be able to utilize the benefit of 50 amp shore power. My suggestion now would be option 2.
Another thought for powering your 2nd A/C would be to feed it from an outlet on the panel after the transfer switch and when on 30 amp shore power unplug the A/C from the outlet and plug it into a 20 amp cord from the campground pedestal. That would only be feasible if you are putting your panels in a bay. Do you know that there are adaptors for plugging your 50 amp shore cord into a 30 amp outlet? No need for a 30 amp shore cord too. There are also adaptors to go from 30 amp to 20 amp.
Do you know that with 50 amp 120/240 shore power that you have 50 amps on each leg for a total of 100 amps at 120 volts? So more than 3 times what you have from 30 amps. Again, sorry if this is being redundant, just trying to help.
Sorry for my poor advise, Sam
Quote from: Sam 4106 on May 06, 2012, 09:22:37 AM
Another thought for powering your 2nd A/C would be to feed it from an outlet on the panel after the transfer switch and when on 30 amp shore power unplug the A/C from the outlet and plug it into a 20 amp cord from the campground pedestal.
Do you know that with 50 amp 120/240 shore power that you have 50 amps on each leg for a total of 100 amps at 120 volts? So more than 3 times what you have from 30 amps. Again, sorry if this is being redundant, just trying to help.
Thanks for being redundant; I need it and it does help!
Right now, the following is giving me insomnia:
1. The neutral and ground has to be bonded, unless connected to shore power, in which case they must be unbonded. Okay, how do I do that? Sounds like a big NC relay would be in order. Is it that simple?
2. I can use [30amp/120v] shore power just like I'd use my generator. Great, that's what I was expecting. Or, I can use the 240 service, which gives me [50amp/120v]+[50amp/120v], which sounds fabulous, except they must be "load balanced." Now I'm confused, since, they'll never be completely in balance, and worse, if I run the inverter on one leg and an A/C on the other leg, I'll blow the beaker as soon as I turn off that A/C. What's the solution -- shut everything down, switch to 30amp, and start up again?
Is there a magic box into which I can plug the 240 service and have it spit out [100amp/120v] so I need not worry about load balancing? Would this even be desirable?
I've read Sean's Odyssey website numerous times. I would like to fabricate an automatic transfer thingamajig like his, but I just don't get it (yet).
Quote from: Midwilshire on May 06, 2012, 10:09:46 AM(snip)
1. The neutral and ground has to be bonded, unless connected to shore power, in which case they must be unbonded. Okay, how do I do that? Sounds like a big NC relay would be in order. Is it that simple?
2. I can use [30amp/120v] shore power just like I'd use my generator. Great, that's what I was expecting. Or, I can use the 240 service, which gives me [50amp/120v]+[50amp/120v], which sounds fabulous, except they must be "load balanced." Now I'm confused, since, they'll never be completely in balance, and worse, if I run the inverter on one leg and an A/C on the other leg, I'll blow the beaker as soon as I turn off that A/C. What's the solution -- shut everything down, switch to 30amp, and start up again?
Just a couple of quick remarks. I'm not really good on electrical stuff so FWIW ...
1) If I understand what you're saying, the neutral and ground must be unbonded when on shore power and connected to the neutral and ground circuits, respectively, of the shore power. Due to the circuits and timing necessary a simple relay won't do it, but there are "automatic" transfer switches available commercially which do this. How you select the right model and design for your needs, I have no clue. Sean can probably suggest an appropriate type for your needs; it may be that he built one "because he can".
2) "Load balancing" is an approximate thing. If you're pulling 35 amps off "one leg" and 37 amps off the other leg, it's not a big deal. If you're pulling 50 amps off one leg and 0 off the other, you're way out of balance and could be running into trouble. And since you'll be constantly switching appliances and other electrical loads on and off (or they may switch themselves on and off automatically if they're on controls like thermostats, etc.), your load balancing won't be exact but if it's close, you're OK. As I understand it, a main problem with load imbalance is that the "return power" that's not balanced goes back down the neutral line into and through the power pole circuit in the campground (or other supply circuit). In the example above, with 35 and 37 amp loads, you're only putting 2 amps down the neutral (this is negligible); the 50/0 amp loads would put the whole 50 amps down the neutral.
I hope that these little items help clarify details (and that I'm right on them).
Quote from: belfert on May 05, 2012, 07:48:43 PM
Most transfer switches unless you build your own will give priority to the generator by default. Why would you run the generator if you have shore power?
many people will run the generator periodically as part of a maintenance schedule whether plugged in or not. In order for this to be effective the generator must have a load applied. With the transfer switch wired as suggested all you have to do is push the start switch and it will take care of itself. Otherwise, you have to manually switch something or plug/unplug somewhere in order to place the load on the generator. If it ain't broke......
Quote from: thomasinnv on May 06, 2012, 11:56:44 AM
Quote from: belfert on May 05, 2012, 07:48:43 PM
Most transfer switches unless you build your own will give priority to the generator by default. Why would you run the generator if you have shore power?
many people will run the generator periodically as part of a maintenance schedule whether plugged in or not. In order for this to be effective the generator must have a load applied. With the transfer switch wired as suggested all you have to do is push the start switch and it will take care of itself. Otherwise, you have to manually switch something or plug/unplug somewhere in order to place the load on the generator. If it ain't broke......
I thought about running the generator periodically to keep it lubed and such as a reason to run it while one has shore power, but it doesn't explain why the OP wants shore power as the priority in a transfer switch.
Quote from: belfert on May 06, 2012, 12:02:44 PM
I thought about running the generator periodically to keep it lubed and such as a reason to run it while one has shore power, but it doesn't explain why the OP wants shore power as the priority in a transfer switch.
I must have used the word 'priority' incorrectly in this context. What I mean to say is: I only want to use the generator when shore power is not available or is otherwise inadequate.
-Mike
Quote from: Midwilshire on May 06, 2012, 01:39:37 PM
I must have used the word 'priority' incorrectly in this context. What I mean to say is: I only want to use the generator when shore power is not available or is otherwise inadequate.
Most RV transfer switches have shore power as the default and will switch to the generator when they detect power on that input. Most don't actually switch over for one to two minutes to allow the voltage to stabilize. They will switch to generator even if there is shore power present.
Hi Mike,
You are right that neutral and ground must be bonded at each source of power and you must keep the neutrals and grounds separate in the bus. Typically the neutrals go on the insulated bus bar in the panel and the grounds go on a terminal strip that is screwed to the metal panel enclosure. The N/G (neutral ground) bond is provided through the shore cord when plugged in, the generator when that is used, or the inverter. The shore/generator transfer switch switches the neutrals along with the hots to keep the neutral and ground separate with those sources of power. The Magnum MS 4024 inverter/charger also switches off the neutral/ground bond when there is power to the inverter/charger and makes the neutral/ground bond when the inverter is suppling the power. So if everything is wired correctly the neutral/ground bond is handled automatically. However, you can't use the generator and shore power at the same time through the transfer switch since the contacters are interlocked electrically or mechanically or sometimes both. That is why I suggested putting an outlet on the panel for the 2nd A/C and using a 20 amp shore cord to power it when on 30 amp shore power.
As Bruce said load balancing doesn't have to be exact. It is more important with a 120/240 VAC generator but I would guess that your generator will be 120 VAC only. There is no magic combiner to create 100 amps of 120 VAC from 50 amps of 240 VAC. If you try that you will be making sparks and smoke.
Quote from: Sam 4106 on May 06, 2012, 03:14:55 PM
As Bruce said load balancing doesn't have to be exact. It is more important with a 120/240 VAC generator but I would guess that your generator will be 120 VAC only. There is no magic combiner to create 100 amps of 120 VAC from 50 amps of 240 VAC. If you try that you will be making sparks and smoke.
if you are referring to shore power, you are correct. But, if you are referring to generator power, many of the 240v generators can be reconfigured to do exactly that. No need for magic.
Here are two other sites that have some good info when you are designing an rv electrical system:
http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/ (http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/)
http://www.jackdanmayer.com/ (http://www.jackdanmayer.com/)
Quote from: Uglydog56 on May 07, 2012, 09:23:32 AM
Here are two other sites that have some good info when you are designing an rv electrical system:
http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/ (http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/)
http://www.jackdanmayer.com/ (http://www.jackdanmayer.com/)
Thanks for that! If you happen to come across any schematics for RV installations, I'd appreciate that as well.
Quote from: thomasinnv on May 06, 2012, 04:02:40 PM
Quote from: Sam 4106 on May 06, 2012, 03:14:55 PM
As Bruce said load balancing doesn't have to be exact. It is more important with a 120/240 VAC generator but I would guess that your generator will be 120 VAC only. There is no magic combiner to create 100 amps of 120 VAC from 50 amps of 240 VAC. If you try that you will be making sparks and smoke.
if you are referring to shore power, you are correct. But, if you are referring to generator power, many of the 240v generators can be reconfigured to do exactly that. No need for magic.
If one were to connect both connections from a 50 amp circuit together inside the RV's subpanel would that cause issues? Would this be considered a short and trip the breaker in the pedestal?
Quote from: belfert on May 07, 2012, 09:32:51 AM
Quote from: thomasinnv on May 06, 2012, 04:02:40 PM
Quote from: Sam 4106 on May 06, 2012, 03:14:55 PM
As Bruce said load balancing doesn't have to be exact. It is more important with a 120/240 VAC generator but I would guess that your generator will be 120 VAC only. There is no magic combiner to create 100 amps of 120 VAC from 50 amps of 240 VAC. If you try that you will be making sparks and smoke.
if you are referring to shore power, you are correct. But, if you are referring to generator power, many of the 240v generators can be reconfigured to do exactly that. No need for magic.
If one were to connect both connections from a 50 amp circuit together inside the RV's subpanel would that cause issues? Would this be considered a short and trip the breaker in the pedestal?
you definately don't want to do that. If you are plugged into a 50/240 shore power you would have problems. Generators that are configured in this fashion (combining both legs of 120 for a single higher amp output of 120) are usually configured at the generator head, not the panel.
My generator is a little different. The head is not re-configurable and to get the maximum output on a single 120 output, both legs are simply "jumpered" together at the transfer switch on the generator side. Most generators you don't want to do this, it will cause problems.
Could anyone answer a very basic question for me?
Can I use both the 30 amp and the 50 amp shore power at the same time?
What I mean is, if I were running a 50 amp coach, but brought along some other stand-alone device, like an air compressor, for example, could I plug this other device in at the pedestal on the 30 or 20 amp circuits if I felt like it, while the rest of the coach is humming along on the 50 amp?
Thanks....
Basic answer...yes.
Quote from: thomasinnv on May 07, 2012, 09:43:42 PM
Basic answer...yes.
Thanks!
So, again with the hypothetical.... if I had four roof airs, then I could conceivably run two on the 50 amp, one on the 30 amp, one on the 20 amp, all at the same time, right?
Not that I would do this; I just want to understand the pedestal.
yes in theory. But you would be ask to leave by most camp grounds as they set their rates by estimating your usage. Some : I have been seeing this more often now, have each site on a maximum size breaker. I don't know size but was at one I kept tripping main for my site(not at site) and was only plugged into 30 amp and it did not tripp at site. (bad breaker at main) moved to differant site no problem. So yes but campgrounds are aware of these practices and it gets into their profits. Some will charge more for 50 amp hookup. For long term stay expect to pay metered rate. Bob
Michael, you changed your question in the last couple of posts. Your first question is could you run some auxiliary component on one of the other outlets on the post. You used an air compressor as an example. As was noted, the simple answer is yes. A better response should be "maybe" as will be discussed later.
Now you are asking if you can run some of the ***installed*** devices on the second outlet. That is a huge difference and I have to ask why? With 50 amp service, you have 100 amps of 110V available and that will run maybe 5 AC units.
In order to run ***installed*** equipment on more that one post plug, you would have to do some fancy wiring. The basic approach would be to have a bank of outlets for each item wired into the bus. You would then need to plug each piece of equipment into its dedicated outlet so that you can run on the basic bus system (post or generator) when you have sufficient power available. Then if, for whatever reason, you needed to run one of those devices off a second outlet on the post, you would need to unplug that device from the bank of outlets and plug it into a cord that runs to the post.
I do this with one outlet in the bus so that I can run an electric heater on the second post outlet when I only have 20 amp available on the post.
Bob brings up the ethics of using more than one outlet on a post. The campground bases their rates on the assumption that you will use a certain amount of power. If you try to double that power consumption, that is "cheating" the campground owner. Most campground are wise to the use of "dog bone" adapters that let you "attempt" to use more than one outlet and they will ask you to unplug one leg.
I use the word "attempt" in the previous paragraph because some of the older campgrounds have the outlets of that post on one leg of a 240V circuit (alternating legs on other posts). Depending on the wiring and breakers you may only be able to get 15-20 amp total on the post no matter how many plugs you use.
Jim
Quote from: Midwilshire on May 06, 2012, 10:09:46 AM
... Is there a magic box into which I can plug the 240 service and have it spit out [100amp/120v] so I need not worry about load balancing? Would this even be desirable?
Just such a "magic box" is commonly known as a
transformer.
However, it's not all magic because transformers are heavy and their use also adds some efficiency losses.
Ted
Quote from: rv_safetyman on May 08, 2012, 05:54:07 AM
Now you are asking if you can run some of the ***installed*** devices on the second outlet. That is a huge difference and I have to ask why?
Because I cannot figure out how to wire it any other way. See my posts above. I ordered George Myers book last night, but this is the plan as of now.
Quote from: rv_safetyman on May 08, 2012, 05:54:07 AM
In order to run ***installed*** equipment on more that one post plug, you would have to do some fancy wiring.
Observe said fancy wiring:
(https://lh5.googleusercontent.com/-QU3J8_P7rpc/T6ksyvK9d8I/AAAAAAAAAKM/ufT5c996iaA/s800/Electrical%2520-%25207a.jpg)
Quote from: rv_safetyman on May 08, 2012, 05:54:07 AM
The basic approach would be to have a bank of outlets for each item wired into the bus. You would then need to plug each piece of equipment into its dedicated outlet so that you can run on the basic bus system (post or generator) when you have sufficient power available.
Funny you should mention that:
(https://lh5.googleusercontent.com/-LeUy8j6KjMY/T6ksyk79X0I/AAAAAAAAAKQ/O2Y8MDDwiQY/s800/Electrical%2520-%25207b.jpg)
Quote from: rv_safetyman on May 08, 2012, 05:54:07 AM
Bob brings up the ethics of using more than one outlet on a post. The campground bases their rates on the assumption that you will use a certain amount of power. If you try to double that power consumption, that is "cheating" the campground owner.
I'm not into cheating anyone, so no problem. One receptacle at a time is fine. My questions were intended to inform my understanding of the pedestal wiring.
Yep, I know that this is atypical, but it works in my mind for any number of permissible power combinations, whereas I cannot make heads or tails of the fancy automatic transfer switches and neutral-ground unbonding, etc. And since I'm not worried about resale, I see little downside to the simple-sailor approach.
Okay, feel free to point out the flaw in my approach, or simply say, "put down the diagonal cutters and back away from the bus slowly."
Mike
Generally, the 50, 30, and 20 amp receptacles are all fed from the same 50 or 60 amp breaker at the distribution. So no, you can't use all three outlets to their capacity.
I think you're making things alot more complicated than need be.
Hi Mike,
I suggest you Google "Magnum Energy Inc", click on Document Library, go to the installation manual for the MS series and find the page(s) that have wiring diagrams for installing the MS 4024 inverter. This is essential reading anyway.
Good luck, Sam
Why not get an inverter that the generator, shore power, and house batteries connect to. The two legs out are one inverted and one not inverted. Split your air conditioners between the two legs. Use the Vanner for the 12 volt loads, a charge controller for the solar, and a battery isolator for the bus to charge the house batteries. You can have an on/off switch to a relay for it if your want. Wouldn't that work and be a lot easier? The plans just seem like over kill. Maybe, I just don't get it.
Don and Cary
1973 05 Eagle
GM 4107
Neoplan AN340