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Author Topic: Vanner Equalizer  (Read 1429 times)
richard5933
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« on: October 26, 2017, 03:31:47 PM »

I've read through lots of posts about this, and I've read through the instructions for the Vanner equalizer. I still have questions.

In the instructions for the Vanner there is an example of an RV setup. Looks to me that this is designed for having 24v systems for both the chassis and house systems. It also looks like they show two equalizers - one each on the chassis batteries and the house batteries. Then I found an example of a system where there were just extra 12v batteries added to handle an additional 12v load. That seemed like what I needed.

There are no 12v loads on the chassis side of my coach. They are all in the RV (house) side of things. I'm pretty sure that means I don't need the Vanner on the chassis side.

Is it possible to just use one equalizer if my goal is to be able to charge the house batteries from the chassis battery/alternator? My thought is that I could connect a Vanner to the chassis 24v battery bank, and then run a 4/0 cable from the 12v post to the house batteries. To keep the systems isolated when the engine is not running, I'd incorporate a constant-duty solenoid in the connection between the Vanner and the house batteries.

If my house batteries are set up as a 12v battery bank, is this a workable solution?

I've attached a modified diagram from the Vanner instructions to show what I have in mind.
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Richard
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« Reply #1 on: October 26, 2017, 04:29:52 PM »

I don't think you want to do the 4/0 cable thing. You're going to severely deplete the lower side of your coach batteries, and that can cause the upper side to get overcharged by your alternator.

Do it the way Vanner shows, with the output from the equalizer. It will be limited to whatever amperage the Vanner is, but over time it will charge your house bank, and will keep the coach batteries equal.


Second thoughts. Initially I thought you were going to run the 4/0 from the battery post, not the vanner post. I reread and looked at your diagram again, and maybe you meant attaching it to the Vanner 12v post. That's correct, however, you don't nee a 4/0 cable. You can size the wire to whatever the Vanner amperage is. if it's a 60 amp Vanner, you can use a 2 ga wire. Solenoid where you show is a good idea, also.

« Last Edit: October 26, 2017, 04:33:22 PM by gumpy » Logged

Craig Shepard
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« Reply #2 on: October 26, 2017, 04:37:32 PM »

I don't think you want to do the 4/0 cable thing. You're going to severely deplete the lower side of your coach batteries, and that can cause the upper side to get overcharged by your alternator.

Do it the way Vanner shows, with the output from the equalizer. It will be limited to whatever amperage the Vanner is, but over time it will charge your house bank, and will keep the coach batteries equal.


Second thoughts. Initially I thought you were going to run the 4/0 from the battery post, not the vanner post. I reread and looked at your diagram again, and maybe you meant attaching it to the Vanner 12v post. That's correct, however, you don't nee a 4/0 cable. You can size the wire to whatever the Vanner amperage is. if it's a 60 amp Vanner, you can use a 2 ga wire. Solenoid where you show is a good idea, also.



I think we're talking about the same thing. I was going to connect the 12v batteries to the Vanner post. I think you're correct though, that the 4/0 would be overkill and probably more difficult to run through the chase than something smaller.
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Richard
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« Reply #3 on: October 26, 2017, 04:53:34 PM »

Richard,
For 17 years and counting we have the power form the alt go to the coach bats and thru a relay and then the house (24v ) bats.  The Vanner is needed only to keep the four house bats equal and supply 12v to the house.  A bit different than your drawing I think.
Works for us.
Frank
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« Reply #4 on: October 26, 2017, 06:15:34 PM »

A Vanner is, at it's most basic, a switching power supply that outputs a 12 volt supply that is exactly half of it's input 24 volt supply.  Your application is using it as a 12 volt supply from a 24 volt source, so completely allowed.  It will supply up to it's limit, and I suggest you fuse/breaker the output to the 12v batteries at maybe 75% of the rated output of the Vanner, like 45 amps if it's a 60 amp model.  The reason is that the Vanner is quite stupid, and doesn't have current limiting circuitry in the same way that chargers do - it will simply put out the power to the extent that it is able, and with three large batteries, it might get asked for a lot if they are well discharged and want to be charged up quickly.  My Vanner does have a resettable breaker on it as well.  I would include a way to disconnect the ground from the Vanner to turn it off if it is not being used, since it will continuously discharge the bus start batteries as long as it's connected to them, at a very low rate, but a very real possibility of damaging the start batteries.
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« Reply #5 on: October 26, 2017, 06:25:11 PM »

Richard,
For 17 years and counting we have the power form the alt go to the coach bats and thru a relay and then the house (24v ) bats.  The Vanner is needed only to keep the four house bats equal and supply 12v to the house.  A bit different than your drawing I think.
Works for us.
Frank

Would there be any advantage to setting up our house batteries at 24v instead of 12v? Of course then I'd have to use the Vanner to supply current to the 12v systems, but it would allow me to keep the current 24v lighting that is in the bus already. Other than the 24v lighting, the only items on the house system currently are two 12-volt radios and a 12v fridge.
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Richard
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« Reply #6 on: October 26, 2017, 08:08:45 PM »

Would there be any advantage to setting up our house batteries at 24v instead of 12v? Of course then I'd have to use the Vanner to supply current to the 12v systems, but it would allow me to keep the current 24v lighting that is in the bus already. Other than the 24v lighting, the only items on the house system currently are two 12-volt radios and a 12v fridge.

The primary advantage would be if you are using a 24v inverter on the house battery. 

Brian has a good point on the house batteries exceeding the output limits of the equalizer if they are deeply discharged. Unfortunately, a fuse is not going to help much, because once they are at that level, they will blow the fuse every time a new one is installed. You will have to charge the batteries up with another source first. You really need a way to limit the current being allowed to be drawn. Unfortunately, that exceeds my limited electrical knowledge. I know there's a way. Adding resistance or something. I just don't know how it's done in a practical sense.


This would actually be another advantage of having a 24v house battery as you could then connect the coach and house batteries using that 4/0 cable and then the alternator will charge them both when connected together. That's how I do mine. Then your equalizer can be used for the minimal 12v loads you have.

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Craig Shepard
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« Reply #7 on: October 26, 2017, 11:38:01 PM »

I do the same as Frank above, 24v House with a centre tap for 12v, the Vanner keeps the two 12v sides equal. By far the best way to handle your 12v loads Smiley
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« Reply #8 on: October 27, 2017, 03:24:04 AM »

Not sure I understand completely. Let's say that I spend a night dry camping and run my house batteries down to 50%. They would take a charge as fast as they could get it. The Vanner would only be able to output up to its limit - in this case 60 amps. Seems like it would be the same thing as plugging in a tiny 10-amp battery charger to a really large battery bank. The charger just keeps plugging along providing 10 amps till the bank is charged.

Wouldn't the Vanner just continue to output its maximum until the house batteries are charged? My understanding is that discharged batteries don't pull current to them, but rather they'll take whatever they can get. Of course I could be wrong.

The Vanner draws 17 milliamps while on standby according to their specs. There is some concern in the instructions about using a negative-side disconnect due to reversed polarity issues. Couldn't a disconnect between the Vanner and the 24v chassis battery bank accomplish the same protection against drawing down the chassis batteries?

I'm going to try and contact Vanner directly to get some additional information about all this as well.
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Richard
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« Reply #9 on: October 27, 2017, 05:11:13 AM »

A bit more about Vanners.

A Vanner can certainly be used as a charger, but it isn't designed in the same way as modern smart chargers.  It just outputs a voltage equal to half of it's input voltage (nominally 12 volts out and 24 volts in, but it has a range of possibilities).  When it's being used as a 12 volt charger in a 24 volt bus, it will pull from the supply side - the bus alternator, which would be running at around 27.5 - 28 volts normally - and charge the house batteries at 13.75 - 14 volts.  If the alternator is not running and the Vanner is left connected to the house bank, any 12 volt loads will be shared between the house bank and the bus start bank - the Vanner will be driven by the 24 volt input from the bus start batteries to keep the house bank at exactly half of the bus bank, and supply sufficient current to do that.  That may or may not be what you want to happen, so you need to have a switch to turn off the Vanner.

If a Vanner is being used to equalize, it supplies a current equal to the load current on it's 12 volt output.  The current is generated by the Vanner being powered by the 24 volt battery, so in an odd way the 12 volt load current is being supplied by both of the 12 volt source batteries, so it acts as though the 12 volt batteries are in parallel to supply the load current, when of course they are in series and actually supplying the 24 volt volt power to run the Vanner.  Kind of neat in my opinion.

My Vanner is connected to equalize my 24 volt house bank, to supply relatively low house 12 volt current loads like lights, a radio, the fridge computer.  My 24 volt house bank also supplies my inverter, which I use to run the TV, microwave, etc, and to run the rooftop AC when the bus is running.  It will run the AC unit when the bus is off, but not for long.  I have a switch to connect the house bank to the bus bank.  That lets me run the inverter from the bus alternator, lets the bus alternator directly charge the house bank, lets me boost the start batteries with the house bank, or even lets me fully disconnect the start batteries and run everything from just the house bank.  Very flexible, very useful.  Many excellent reasons to have a 24 volt house bank in a 24 volt bus, and to use a Vanner to supply small house 12v loads, but you have to design it that way to make it work.

A Vanner can be a charger, but it doesn't work in the same way as a modern smart charger does.  A modern three stage smart charger has a bulk stage where the current is limited and the voltage varies, then an absorption stage where the voltage is limited and the current varies, and then a maintenance mode where the voltage is reduced and the current is limited to a trickle charge.  All the Vanner can do is an approximation of the absorption stage, with a constant voltage controlled by the bus alternator, and a reducing current controlled by the increasing state of charge of the house bank over time.

Brian
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« Reply #10 on: October 27, 2017, 12:53:11 PM »

I spoke with the folks at Vanner today. Sounds like there would be no problem using a 66-100 as a charger, but it's certainly not the cheapest thing in the world. It also doesn't provide any type of smart charger features.

Right now I'm leaning towards having a 12v house battery bank. I will install separate 120v chargers for both the house and chassis battery banks for use when on shore power/genset. The main goal of installing the Vanner was simply to be able to charge the house battery bank while on the road. The only 24v loads in the coach right now are interior lights and water pump, and they will be converted to 12v soon. Lighting will be changed to LED and I'll simply install a 12v pump.

For just over half the price of the Vanner, it looks like I can purchase something like this:
http://www.sterling-power-usa.com/SterlingPower24volt-to-12volt-dc-to-dc-batterytobatterycharger.aspx

Seems to me that this would be a better way to go all around, especially since this will provide smart charging for the house batteries while on the road. From the manual, it looks like it won't pull any current from the chassis batteries unless the alternator is providing charge, and in many ways sounds like the Xantrex Echo Charger but on steroids.

Thoughts?
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Richard
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« Reply #11 on: October 28, 2017, 02:46:25 PM »

Do you have any of this equipment yet? If not...

A Vanner Equalizer is not the first thing I would buy as a 12 volt house bank charger.

That isn't their purpose, even if it "functions" It gets used as a power supply in buses, not as a charger. As already written, it will make a pretty dumb charger. Dumb = abusive to your batteries, compared to the other marvelous options available.

The coach alternator quickly goes to minimum voltage after a start, as the start batteries are effectively fully charged. the house batteries get half of that... mess with the regulator, and you start boiling the starts in a feeble attempt to charge the house.

You have a big alternator already, why not access all that available power and design the house bank to that voltage?

Or, if committed to 12 volt, why not add a proper externally regulated alternator and smart regulator to the engine?

Lots of ways to do this without complicated and perhaps uncharted area using a Vanner EQ?

happy coaching!
buswarrior

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« Reply #12 on: October 28, 2017, 04:07:34 PM »

Do you have any of this equipment yet? If not...

You have a big alternator already, why not access all that available power and design the house bank to that voltage?

Or, if committed to 12 volt, why not add a proper externally regulated alternator and smart regulator to the engine...
Haven't bought anything yet...

I'm definitely leaning against the Vanner. Not smart enough to charge the house batteries properly.

Definitely want the house batteries to be 12v. Everything we're going to run is 12v, so it makes no sense to have a 24v house system - we'd still need a Vanner to supply the 12v devices.

Right now that leaves me to figure out how to charge the house batteries while driving. Unless there is a pre-made kit to add a 12v alternator, that is out. I'm not ready to engineer something like that right now.

Which is why I'm leaning towards the 24v-to-12v battery charger. I linked to the Sterling one earlier. It looks like it would provide up to 70 amps for the 12v house system as long as the bus alternator is running.

Any one have experience with one of the 24v-to-12v battery chargers like the one I linked to?

Or, does anyone have photos they can post that show how to safely mount an auxiliary 12v alternator to the 8V71? If it can be done with off-the-shelf parts I might be up for that.

Richard
1974 GMC P8M4108A-125 (Current bus)
1964 GM PD4106-2412 (totalled Sept 2017)
Located in beautiful Wisconsin
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« Last Edit: October 28, 2017, 05:39:08 PM by richard5933 » Logged

Richard
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« Reply #13 on: October 29, 2017, 04:36:05 AM »

I think the reason Vanners are so ubiquitous in the hobby bus world is that they usually come for free with the bus, or are obtained very cheaply used.  I think the reason most people with a 24 volt bus lean towards a 24 volt house bank is so they can charge it for free from the bus alternator, so they can run a 24 volt industrial sized inverter with reduced cable sizes, and because they already have a Vanner for free.  Carefully analyze your downstream power needs to make sure you don't need a 24 volt inverter.  If you don't, then a 12 volt battery bank starts to make a lot of sense.  Adding a second alternator for your 12 volt house bank can be the cheapest way, but your DC to DC chargers look well thought out.

As stated earlier I personally went with a 24 volt house bank, for two killer application reasons.  One is I use a large 24 volt inverter to run my air conditioner while driving, powered from the bus alternator.  The second - and it's saved my wallet big time several times - is that I can run my bus off the house bank if I lose a start battery (which I did) and I can use the house batteries to boost the start batteries when it's cold out and the engine is hard to start.  Those two applications make a 24 volt house bank mandatory for me.
« Last Edit: October 29, 2017, 04:39:12 AM by bevans6 » Logged

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« Reply #14 on: October 29, 2017, 05:35:46 AM »

when I 1st built the coach I set the house system bank 12 v and it worked ok but it was a big drain on the batteries when I was using the inverter and it took a lot longer to charge the 12 v bank . when it was time to change the batteries I redid the system to 24 v for coach and 24 v for house and a new hybrid inverter
and added a 24 v to 12 v converter for all the 12 volt stuff and in amps it was not much

1000 times better

dave
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dave , karen
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« Reply #15 on: October 29, 2017, 07:58:27 AM »

Ok, since we're still working on plans... here comes the devil's advocate:

What are all these 12 volt devices, and why?

Ignore history. All that #$%&$^&* camping and RV "thought process" steaming bovine waste stuff.

In late 2017, why wouldn't you design your coach to work just like your house? Heck, even using the same appliances, carried out to the coach as part of packing for the trip?

Why would using your coach, and spending thou$and$ on an electrical system, be even an inch less convenient, or different, or difficult, or oppressive, than living at home?

The Busnut pleasures himself with the manipulation of the machine, the more switches, wires, valves, procedures, open baggage doors, stuff to remember... the more he feels the master of his environment.... but the busnut is rarely alone in this adventure...

I DARE YOU... the Significant Other silently puts up with the Busnut Shittery, right up until the snapping point... If you have to open even one single baggage door to fool with the electrical on a regular basis, the clock is ticking...

SO...BS

Beyond a 12 volt automotive sound system, and a CB radio, what else might be 12 volt?

The better LED don't care whether they get 12 or 24 volts.

Cost/complexity/benefit ratios might suggest the cheapest way is the path beaten down by the masses: 24 volt battery bank, big inverter charger, new 3/4 stage regulator for the existing 24v coach alternator, a combining device to tie all the batteries together while on the road, a used transit bus Vanner EQ or any smaller size for the radios, put on the house bank, cuz, you listen to the radio while camping.

Start batteries, if you keep 'em, ONLY start the engine and power the chassis systems that religiously do not get used while camping.

The big savings is figuring out how to use the existing big alternator. The new multi-stage regulator is key for proper charging on the typical camper daily move of a couple hundred miles or less, the stock regulator needs more time than you will drive on many days, leaving you under-charged entering the campsite. Heavy cabling $$ for 12 volt can't be ignored. Features on a wider range of available inverter/chargers at the 12 vs 24 volt...

We all build our own, to make it our own.

Keep the ideas churning!!!

happy coaching!
buswarrior



 

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« Reply #16 on: October 29, 2017, 08:34:01 AM »

  ... I DARE YOU... the Significant Other silently puts up with the Busnut Shittery, right up until the snapping point.... 

        Wise point to remember.  If you get on the wrong side of The Management, you may be forced to install a cast iron big-foot bath tub to make amends.
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« Reply #17 on: October 29, 2017, 09:56:46 AM »

Have you got more information on the new 3/4 stage regulator for the 24v bus alternator? Maybe a link?

Richard
1974 GMC P8M4108A-125 (Current bus)
1964 GM PD4106-2412 (totalled Sept 2017)
Located in beautiful Wisconsin
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« Reply #18 on: October 29, 2017, 10:19:20 AM »

Here is a link. This makes sense for marine use where engines are run for days on end but most of us don't run our buses long enough to justify these regulators.

http://www.balmar.net/
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« Reply #19 on: October 29, 2017, 01:33:14 PM »

well... (imo)...u don't need DC current to listen to music/radio either.

house and chassis can easily be the same in this day and age.

and you can do it all without a Vanner.

you might need two more batteries.

lots of my 110v needs are run thru my inverter 24/7 and have been since day one.

inverter feeds a 110v AC sub panel. and minimal 12v lighting
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« Reply #20 on: October 29, 2017, 01:52:08 PM »

It didn't make sense to me to run 110 volt lighting off my inverter.  I run a 24 volt inverter so I can get power from my big 50DN.  It also makes the cables to the battery smaller.  I kept my 24 volt overhead lights since they were already there.

24 volt stuff: water pump, front lights in kitchen living area, rear lights in bunk area
12 volt stuff: radio, Fantastic vents, bathroom light, hallway LED light, Proheat heater and fans for heater, lights and 12 volt outlets in bunks
110 volt stuff: Air Conditioners/heat pump, refrigerator, microwave

I don't have a significant other.  The guys I travel with all know how to start the generator if they want to use heat or air conditioning.
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« Reply #21 on: October 29, 2017, 02:57:43 PM »

well... (imo)...u don't need DC current to listen to music/radio either.

house and chassis can easily be the same in this day and age.

and you can do it all without a Vanner.

you might need two more batteries.

lots of my 110v needs are run thru my inverter 24/7 and have been since day one.

inverter feeds a 110v AC sub panel. and minimal 12v lighting


So many questions about this...

If your house and chassis systems share the same batteries, how can you be certain that you can start the bus in the morning?

If I run household devices through an inverter, aren't I really wasting a lot of the battery capacity to the losses of conversion? Since many modern AC devices are actually running internally on DC, seems like a waste to first convert DC to AC only to have the device convert it back.

When we are boon docking we run a fairly minimal system. There is a 12v roof vent, a 12v fridge, 12v water pump, 12v LED lighting, and the 12v sound system. In cooler weather we also need to run the blower on the furnace. At this point I'm not sure if the furnace blower is 12v/120v or 120v only, so it might need to be on the inverter until I can get that upgraded to 12v. The only luxury we allow ourselves when not on shore power is usually a flat screen TV and Blue Ray player through the inverter, usually for only a couple of hours max. We use propane to cook and run the genset long enough to heat the hot water tank for a couple of short showers in the morning. In the warmer months when a/c is needed we'll have to run the genset as our basement a/c units won't run easily on inverter.

I plan to install an 1800-watt inverter to power the furnace and a few outlets for TV, etc. I know that using a 12v inverter requires larger cable than 24v, but according to the Xantrex information they both 12v and 24v versions function at about a 90% efficiency.

The big question I had at the beginning of this thread is how to best charge the house batteries while driving down the road. After reviewing the currently posted info, the two viable options are:

    -Set up a 24v house battery bank which is charged directly from the bus engine alternator while driving. This would then require the use of a Vanner to pull 12v from the house battery bank for the various 12v devices. Advantages would be the ability to jump start the bus from the house batteries, and the simplicity of charging by flipping a switch to engage a bridge solenoid.

    -Set up a 12v house battery bank which is charged by the use of a 70-amp 24v to 12v battery-to-battery charger while driving. Big advantage to me of this setup is the simplicity of the 12v side and the ability to use over-the-counter equipment for virtually everything.

Either way, I'm going to use 6-volt batteries for the battery bank. Previously I had installed four Trojan T-145 for a total of approx. 575ah at 12v. I have more than enough room in this bus for four Trojan L16 batteries which would give approx. 960ah at 12v. Regardless of which I choose to use on this bus, they can be configured for either 12v or 24v use so I'm not permanently locked into either.

Couple of other notes...I know that if I go with a large battery bank it will take a long time to charge using whatever setup I choose. Hopefully we'll add rooftop solar to help that down the road. No rooftop a/c units, so there is plenty of room for solar. I'm planning to install a 120v ac 70-amp charger (assuming 12v) so it should take about 8 hours or less to recharge from 50% on shore power. Also important to note that we're not trying to re-create our house in the bus. Neither of us is expecting nor desires things to be as easy as it is at home. I have full buy-in on having to flip a couple of switches on the inside control panel to energize devices & outlets to run from the inverter when necessary. We're also both in agreement that we don't want to redo the interior at this time to accommodate household-sized appliances. We both really love the retro 1970s vibe in our new bus and are willing to put up with some inconvenience to keep that, at least for now.

I'm dutifully taking notes as comments are added. At some point this winter I'll hit the 'buy' button and start assembling a system. Till then, I hope that you'll continue to provide input on the various ways to accomplish this. If anyone has first-hand experience with the battery-to-battery chargers I'd love to hear about it as that's one of the big unknowns at this time.
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Richard
1974 GMC P8M4108a-125 (Current Bus)
1964 GM PD4106-2412
Located in beautiful Wisconsin
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« Reply #22 on: October 29, 2017, 03:31:38 PM »

my generator has it's own battery.
there is not enough real estate on a bus to use solar to replace a charger (imo)
you will always need to top the batteries. solar will not be there when u have to have it. Murphy's Law applies.
an inverter with a 130 amp charger will more than pay it's worth in premature battery deaths... if you bake bread or vacuum or whatever...you're going to run a gen or pole sooner or later. frequently is better...
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Donald PH
1978 Model 05 Eagle w/Torsilastic Suspension,8V71 NA, DDAllison on 24.5's 12kw Kubota.
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Previously owned by Wee Willie Ent.
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« Reply #23 on: October 29, 2017, 04:16:03 PM »

my generator has it's own battery.
there is not enough real estate on a bus to use solar to replace a charger (imo)
you will always need to top the batteries. solar will not be there when u have to have it. Murphy's Law applies.
an inverter with a 130 amp charger will more than pay it's worth in premature battery deaths... if you bake bread or vacuum or whatever...you're going to run a gen or pole sooner or later. frequently is better...


Agree that generator needs its own battery. That's in the plan for now. The current setup is that the gen battery is also the house battery. Bad idea and soon to be changed. I'll add a small alternator to the Perkins diesel powering the gen so that it can top off its own battery.

I'd love to run a 130-amp charger. Problem is that I simply don't have adequate wiring for it in the current 120v system. There are a couple of 20-amp breakers, but they're taken and the rest of them are only 15 amp. The most I can safely run on a 15-amp breaker is a 70-amp charger. I was using the Progressive Dynamics 9270 on our previous coach and plan to do the same again. Eventually I'll have to rewire the 120 breaker panel to provide more capacity, but until then I'll run with the max that I can safely. I'm also going to keep the charger and inverter separate for now since I'm not going to be running it with an automatic transfer setup.

Solar will be added to augment, not replace, the use of shore power or generator. Depending on how many panels we can initially get on the roof and how we configure the MPPT system, we should be able to add 15-30 amps charging capability while the sun is shining.
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Richard
1974 GMC P8M4108a-125 (Current Bus)
1964 GM PD4106-2412
Located in beautiful Wisconsin
KD9GRB
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« Reply #24 on: October 30, 2017, 05:28:15 AM »

this is the inverter charger I used and a small 24 v to 12 volt electronic converter like this but mine was only 20 amps and I put a small 12 volt screw gun lith . battery in line to boost the amps if needed . my largest draw was the slide out motor 1 1/2 hp at 24 volts stepped down to 12 volts for a slower speed

http://www.samlexamerica.com/documents/product-specs/12004-SDC-30-0715.pdf

https://www.solar-electric.com/magnum-energy-msh4024re-hybrid-inverter.html

dave
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dave , karen
1990 mci 102c  6v92 ta ht740  kit,living room slide .... sold
2000 featherlite vogue vantare 550 hp cat
 home base huntsville ontario canada
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« Reply #25 on: October 30, 2017, 07:21:16 AM »

A few broader statements to delve into:

"If your house and chassis systems share the same batteries, how can you be certain that you can start the bus in the morning?"

Because the system has been designed and sized correctly, you manage your power properly, a battery monitoring system is used, (like this one, just buy one, from here or somewhere... https://marinehowto.com/smart-gauge-battery-monitoring-unit/  ) Do you wonder if you have enough fuel for today's trip? Then why would you wonder if there are enough electrons to spin the starter...? Exactly the same issue, but not in many minds...


"If I run household devices through an inverter, aren't I really wasting a lot of the battery capacity to the losses of conversion?"


eagle 19952 suggested maybe adding 2 more batteries. Do the math, exactly how much amp/hrs are we fretting about, for what advantage/disadvantage? limiting yourself to a dark cave, inadequate 12 volt devices, for how many amp/hrs? What is the "loss of efficiency" for any other part of a conversion? We don't fret about how much fuel turns into heat instead of motive force from the engine? You already know to buy a good name brand inverter above 90% efficient, so.... "a lot" might not be the term?

"I know that if I go with a large battery bank it will take a long time to charge using whatever setup I choose."

You have to put back what you take out. And actually, a much larger battery bank can be charged harder and quicker to replace a given amount of power taken out, due to its ability to absorb a higher charge rate. We need a link to one of these C10 C15 C20 articles...?

You already are on track for using solar to finish your daily charge, you want BIG amps, to quickly get you to where the solar can readily finish the job.

"I'd love to run a 130-amp charger. Problem is that I simply don't have adequate wiring for it in the current 120v system."

This might be the cheapest part of the job? Down to Home Depot and fix this.
 
The rest of your system is being held back by what pittance of readily available box store pieces? Back to the invisible electric design, a high power charger pounds how much power into your batteries in the 30-45 minutes you run the generator for breakfast... and then you have a Balmar regulator for the big Delco alternator ( http://www.balmar.net/?product=regulator-mc-624-h ) that will put how much more power into the batteries on a leisurely 1-3 hour drive down the highway to the next camping spot? And then an afternoon of solar input of how much more?

Without quantifying the power consumption, and then a real model of returning that power, you can't make confident deci$ion$?

My experience? I went straight to the top from the beginning, buying the old Trace 4024, because of reading the tribulations of other busnuts, trying to save money, and in the end spending far more, putting in inadequate stuff, and having to re-do it. That, and some horrible foolishness with mobile command and mobile training vehicles, constant foolishness, foolishness, foolishness. I vowed to never own something that did not simply "do the job".

Don't get me wrong, we are all FREE to experiment as we please, this is a HOBBY after all!!! Some busnuts live for fooling with the machine, spending a bit of money carelessly is part of the adventure of the experience, others, just want to go camping.

The Significant Other's true wishes are rarely spoken, even when the busnut is trying to listen...

"Neither of us is expecting nor desires things to be as easy as it is at home. I have full buy-in..."

Yeah? We've heard that from lots and lots of male busnuts... until you camp beside a well designed conversion and she watches wistfully out the window at the neighbours, drive in and "just start camping", and drive away with just as little "entertainment"... while she has to wait while you jump through hoops to change configuration for everything... Lock her up, don't let her talk to the other "her", they will compare notes and when she finds out they spent the same amount of money as you did.... LOL, and a wink, but seriously... is she reading these threads with you?

Some want to learn by doing, some want to learn by watching the misadventure of others...

So long as it is informed decision making... into the breach!

Hooray that we all meet up on here!!

happy coaching!
buswarrior
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Frozen North, Greater Toronto Area
richard5933
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« Reply #26 on: October 30, 2017, 11:10:59 AM »

...This might be the cheapest part of the job? Down to Home Depot and fix this....
happy coaching!
buswarrior


Thanks for all the information. I've got lots of homework to do before ordering parts and getting to work. First step will be for the two of us to figure out our priorities and decide which set of benefits fits our needs best.

Oddly, the one thing that will get me in trouble fast on the home front is if I do anything to mess with the look of things and detract from the 'cool 70's vibe'. If I replaced the existing 120v panel with a standard HD gray breaker panel, no matter how well I concealed it in a cabinet or closet, I might be in the bus alone. Keeping the vintage look and feel is going to be a priority and make upgrading the 120v service and panel a bit trickier than just ripping things out and replacing them. Someone had already done this on our 4106, so I had a much easier time in this department when upgrading to 50-amps. On this bus I'm going to have to find a way to add the more modern underpinnings and safety features while keeping the original look. I'm going to take this part slowly, even if it means living with the current 120v system and making less-than-ideal upgrades for now.  Eventually I'm sure I'll be told that it's time to put in a proper 120v panel, and hopefully there will be a replacement for our current marine panel that will be acceptable and keep the proper look.
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Richard
1974 GMC P8M4108a-125 (Current Bus)
1964 GM PD4106-2412
Located in beautiful Wisconsin
KD9GRB
eagle19952
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« Reply #27 on: October 30, 2017, 11:46:42 AM »

If I replaced the existing 120v panel with a standard HD gray breaker panel, no matter how well I concealed it in a cabinet or closet, I might be in the bus alone. Keeping the vintage look and feel is going to be a priority and make upgrading the 120v service and panel a bit trickier than just ripping things out and replacing them.

best learn to live with what you have then....
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Donald PH
1978 Model 05 Eagle w/Torsilastic Suspension,8V71 NA, DDAllison on 24.5's 12kw Kubota.
Wants Paint Smiley
Previously owned by Wee Willie Ent.
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« Reply #28 on: October 30, 2017, 04:05:52 PM »

If you have 4 house batteries and two coach batteries, 24 volts , do you really need a 12 volt battery for the generator? Couldn't you draw 12 volts from either set of batteries or the Vanner. It isn't going to take much to start a generator. What am I missing here?
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GMC h8h 649#028 (4905)
Pennsylvania-central
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« Reply #29 on: October 30, 2017, 04:38:40 PM »

The existing period electric panel may continue to do its thing out in the open.

The controls on its face can be used to trigger your upgraded pieces for maximum battery charging, and whatever else you dream of doing, that the existing panel, as currently used, cannot?

Think of turning existing panel into a switching device, and put the modern protection and distribution elsewhere out of sight?

You can have your cake, and eat it too?

happy coaching!
buswarrior





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Frozen North, Greater Toronto Area
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« Reply #30 on: October 30, 2017, 06:32:31 PM »

After a couple months of 95% boondocking and a handful of days on the pole this is where I land on the electrical topic.

Coach configured as follows:

Start batteries - 2 x 12v (series) Grp 31 start
House batteries - 4 x 6v (series) Golf cart deep cycle
Generator battery 1 x 12v start

Generator - 2 x 120v x 33 amps
Vanner inverter/charger 3400 watts 120v x 30amps continuous
Vanner 12v equalizer - 60amps

120v
numerous wall plugs
microwave
AC x 2 roof
hot water heater
lighting

12v
lighting
stereo
alarm system

propane
Dometic refrig 3 way (running on propane)
stove/oven

Generator battery - critical. There have been multiple times when house and start batteries were failing and the generator pumps enough juice into the batteries to be able to start the coach. One time the generator battery was dead along with the others and then zero way to start the coach. Got a jump on the gen battery, started generator, started coach.

Generator required to run the AC, hot water heater, coffee maker, and microwave if used for more than a few minutes.

Typically, house and start batteries are not connected together. House batteries and generator run everything in the coach. Generator runs for an hour or two in the morning to recharge house batteries, make coffee, heat up the hot water, heat up any morning food in the microwave. During the day, house batteries are used for TV or other connected devices such as laptop and phone chargers. Generator runs about an hour during the early evening to charge up house batteries, power kitchen stuff, lights.

Planned upgrades - Add 400 watts solar to fully charge house batteries and allow running the refrig on electric instead of propane. If not sufficient add another panel or two.

Some folks strive to eliminate the generator. My goal is to minimize the need for the generator but acknowledge it is going to be used in conjunction with solar to deliver all the needed energy.
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Don F
1976 MCI/TMC MC-8 #1286
Fully converted (June 2017)
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« Reply #31 on: October 30, 2017, 07:00:12 PM »

The generator is definitely the most important thing on my bus. The solar panels do help too. But overnight in a rest area or Walmart without hook ups at 20 below in the winter, and the genny is indeed essential...

JC
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JC
Blackie AB
1977 MC5C, 6V92/HT740
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