Electrical System Set-Ups

[Long Ride]

Will anyone share information about the electrical system provided in the Reflections and what set-ups they are using to maintain battery banks? Are there any solar users out there, truck alternator sizing and set-ups, etc. We're thinking of some boondocking mixed in with the campground stays.

 

[TucsonJim]

We are using two 6-volt AGM batteries and have two 100 Watt panels that we've attached to 50 foot cables. That way I can move the panels throughout the day to stay in the sun if needed. I also have a 3000 Watt Honda generator in case we need to run the AC, etc. So far, I've rarely used the generator. The solar bank provides all the power we need to keep the batteries charged.

 

[Long Ride]

We are using two 6-volt AGM batteries and have two 100 Watt panels that we've attached to 50 foot cables. That way I can move the panels throughout the day to stay in the sun if needed. I also have a 3000 Watt Honda generator in case we need to run the AC, etc. So far, I've rarely used the generator. The solar bank provides all the power we need to keep the batteries charged.

Are you charging the house batteries with the truck alternator while driving?

 

[bc1iron]

We have 3 x 150watt roof mounted panels, a blue sky 50 amp controller, a 1750 watt inverter. Since I have a feed direct from the inverter to the coach breaker box, I made my own transfer switch that disables the on board converter (bat charger) when the unit 110v is sourced from the inverter. It makes no sense to power the onboard battery charger by way of an inverter that is pulling power from the batteries that are being charged.....never ending inefficient loop.
I run 6, 6volt batteries that are in the very front compartment, I ordered a marine grade battery box that is vented thru the factory bat vent grill. I have a remote inverter switch located inside the unit.

Works excellent, push one button that activates the inverter, all interior 110 plugs and fixtures are useable. Microware can be run for short periods of time with no issues, not enough power to run A/C. We had this set up in our previous trailer. Over the course of 5 years I have only had to run may generator 3 times due in order to charge batteries. We dry camp approx. 40 nights per season. Watch Sat TV, use the coffee maker etc as per usual. We have camped for as long as two weeks without shore power with no issues. I carry a Honda 1000 watt gen, if I get in a pinch, I have a stand alone battery charger I run off the generator and hook directly to the battery bank.

Luv it, simple to use, with the exception of regular battery service, no maintenance required.

 

[Cate&Rob]

Randy,

You have described almost exactly the setup I have on my boat !
On my Reflection 303 and "small truck", I just can't carry 6 golf cart batteries in the front compartment !!
If Grand Design wanted to really get "ahead of the game" for dry camping, they would/could provide space for a large battery bank aft of the trailer axles.
Then I could carry lots of batteries . . . and reduce my pin weight .

Rob

 

[TucsonJim]

Are you charging the house batteries with the truck alternator while driving?

Yes, I'm charging while driving.

 

[Long Ride]

Yes, I'm charging while driving.

You seem to have perfected this set-up. I wonder if you would mind sharing a wiring diagram by posting it on the Forum? It would really help those of us that want the boondocking capabilities with out the learning curve.

 

[Long Ride]

We have 3 x 150watt roof mounted panels, a blue sky 50 amp controller, a 1750 watt inverter. Since I have a feed direct from the inverter to the coach breaker box, I made my own transfer switch that disables the on board converter (bat charger) when the unit 110v is sourced from the inverter. It makes no sense to power the onboard battery charger by way of an inverter that is pulling power from the batteries that are being charged.....never ending inefficient loop.
I run 6, 6volt batteries that are in the very front compartment, I ordered a marine grade battery box that is vented thru the factory bat vent grill. I have a remote inverter switch located inside the unit.

Works excellent, push one button that activates the inverter, all interior 110 plugs and fixtures are useable. Microware can be run for short periods of time with no issues, not enough power to run A/C. We had this set up in our previous trailer. Over the course of 5 years I have only had to run may generator 3 times due in order to charge batteries. We dry camp approx. 40 nights per season. Watch Sat TV, use the coffee maker etc as per usual. We have camped for as long as two weeks without shore power with no issues. I carry a Honda 1000 watt gen, if I get in a pinch, I have a stand alone battery charger I run off the generator and hook directly to the battery bank.

Luv it, simple to use, with the exception of regular battery service, no maintenance required.

bc1iron - you too seem to have perfected this set-up. Would you mind posting a diagram on the Forum? Many thanks.

 

[TucsonJim]

You seem to have perfected this set-up. I wonder if you would mind sharing a wiring diagram by posting it on the Forum? It would really help those of us that want the boondocking capabilities with out the learning curve.

I wouldn't mind at all. But I'll need to post some pictures to show How I installed the solar set up. Currently, my 337 is back at the factory in Indiana for some repairs. As soon as I get it back, I'll post my set up.

Jim

 

[offtohavasu]

Looking forward to it Jim. Even though we're looking at a different line (Momentum) the theory still applies. When we're out in the Dunes for a few days at a time, the solar will be very handy.

 

[Norcalrv1]

I am also interested in how you did this. When I had a trailer I went from an external battery to the inverter to the external electrical cord and then disconnected the converter and things did not work. May not have had enough power to make it work. I should not have been in a loop with the batteries which were connected to the trailer. Your comments will be most welcomed.

Hope you get your 337 back. We had some issues with ours and have mobile RV service do repairs. Grand Design reimbursed me. Can't complain about that.

Rod Zebb
Fairfield, CA.
Reflection 337, number 263
2014 RAM 3500 turbo diesel

 

[Cate&Rob]

An important component for any "dry camping" battery system is a precision battery monitor.
http://www.victronenergy.com/battery-monitors/BMV-600S and BMV-602S/ is what I use on my boat and one will eventually be added to the RV. This gauge can measure exact current flow and keeps a running total of all the Ah in (from any type of charging) and all the Ah out from any loads. For example, this gauge will tell you exactly how many amps your solar panels are putting in or how much each light or other accessory draws. Trying to judge state of charge from the LED battery gauge on the controls panel is way too coarse a measurement to mean much. A fully charged battery (or bank of batteries) is at 12.7 V. At 50% charge it will be at 12.2V. Half a volt to try and distinguish good from bad.

I have spent a lot of years building and rearranging battery systems on my boat and for others. I will be interested in following this discussion as well.

Rob

 

[Norcalrv1]

Thank you, Rob. That is good information to have. The difference between a fully charged battery and only 1/2 charge is not much voltage. Currently I use a digital volt meter.
Rod

2014 Reflection 337, number 263
2014 RAM 3500

 

[bc1iron]

Rob,

The ideal set up is to balance your solar charge capacity with the amp hour capacity of your Battery bank. A good rule of thumb is to have aproxamatly the same amp hour capacity in your battery bank as you do wattage out put of your solar array. In my case, 450 watt solar would effectively support a 450 amp hour bat bank. Keep in mind, when you pair two 6v 225 amp hour batteries, you don't get 450 amp hours, you get 225 at 12v! So in my case, I have 3 battery "pairs" at 225amp hour, for a total of 675 amp hours. Ideally I should add another panel or drop two batteries.

You may ask; "why would less amp hour capacity be a good thing?" You have to remember, once you run down or deplete you battery power, the more capacity you have the longer it will take to fully recharge. Ideally, you want to be able to fully recharge your battery bank in one day. Given that my set up may be short on charge capacity, I could in theory, run down my batteries late in the evening and early the following morning and not be able to bring them to full charge the next day. This would not be good.

My plan is to add one more 150w solar panel to balance my charge capacity to my battery amp hour capacity.

Randy,

You have described almost exactly the setup I have on my boat !
On my Reflection 303 and "small truck", I just can't carry 6 golf cart batteries in the front compartment !!
If Grand Design wanted to really get "ahead of the game" for dry camping, they would/could provide space for a large battery bank aft of the trailer axles.
Then I could carry lots of batteries . . . and reduce my pin weight .

Rob

 

[bc1iron]

Long Ride,

I may be able to add some photos this weekend. As you may have noted, I live in snow country this time of year.

 

[bc1iron]

Rob,
You bring up an excellent point, "Voltage is not a true indicator of available power usage or reserve."

Further to this, the most important and most over looked piece of the puzzle is wire size and length of run. In my case, I made all the cables that run between my batteries #1 gauge wire and the cables that run from the battery bank to the inverter (heaviest load in system) are #4 gauge with length under 4ft. From the roof mounted panels, I chose to go with double #8 wire due to the length of the run.

Although large wire is expensive, keep in mind that lighter gauge wire at low voltage can result in a large loss of efficiency. In some cases up to 20% Your money is better spent on good heavy wiring than having to add an additional panel to off set the inefficiencies of a cheap, lightweight, poorly planed layout.

 

[Norcalrv1]

Excellent information, thank you so much.
Rod

 

[Cate&Rob]

Hi Randy,

We have obviously travelled similar paths through balancing battery bank size, consumption rate and charging capacity.

I agree with what you say WRT maximum wire size and minimum length of run being very important.
I would add to this that quality of connectors and how they are crimped is equally important. Borrowing or buying a proper “battery lug” crimping tool is well worth it.
BTW, a good source for reasonably priced good quality heavy gauge wire and lugs is a welding supply store.

WRT battery capacity, the optimum range to discharge and recharge lead/acid batteries is between 50% and 80% state of charge.
Going below 50% risks permanent damage to the battery and going above 80% is great if you can get it, but takes an increasingly long time.
This is where a precision battery monitor becomes really useful. It can be programmed with the Ah capacity of the bank and will display state of charge as a %.
So, you know in the morning, what the bank is at (presumably between 50% and 80%) and how much you need to regain during the day.

Using your 450 Ah bank as an example, 80% is 360 Ah, 50% is 225 Ah . . . so you should ideally live within 135 Ah consumption and recharge per day.

A 450 watt solar array is going to be putting out a maximum of about 34 amps at an optimum 13.5 volts charging voltage.
The instantaneous rate of charge can be displayed on the monitor and will show how much of that theoretical 450 watts (34 amps) is actually going into the bank.
You will be able to see the effect of panel orientation to the sun, cloud cover, rate of charge acceptance by the batteries (goes down as bank % goes up), etc.
Then you can decide whether you really need to run the generator or the truck to catch up .

Rob

 

[bc1iron]

Rob,

Agreed,

Re: connectors, I am old school in this regard. While the quality of the crimping tool is critical as not to loose all the effecency you gain with heavy wire by running thru a poor quality connection, I prefer to actually solder the lugs to the wire. It takes a little work, proper fluxing and shrink wrapping, but in the end I feel better with a connection that provided better continuity by way of larger contact surface. Further to this, the shink wrap provides a weather tight seal to minimize corrosion.

In terms of charge effecency. Most battery manufacturers recommend a charge rate of 14.5v + - in oder to achieve a 100% charge. Yet most charge controllers come pre set with a cut out point at 13.4v. Charging at this voltage, no matter how long, will never allow you to aceive a 100% charge. The best way to truly determine if your bank is fully charged is to take specifc gravity readings on each cell with a hydrometer after you have allowed the battery to "rest"

 

[Cate&Rob]

Hi Randy,

"Equalizing" cells at 14.5 V to reach 100% is a technology of very sophisticated battery chargers.
But, you are absolutely correct.

I also used to solder terminals until I discovered the lug crimpers used to attach welding cable lugs.
The problem with soldering (at least in the marine environment) is that the flux keeps corroding things.
Shrink wrapping is a way to seal in the flux acid . . . but is not required with crimped connections.

Good discussion !!

Rob