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solar charging engine batteries

Finally decided I have had enough of the Battery Minder smart charger as it was after a day showing 'reverse Polarity" and discharging the batteries. No matter what I did it would do the same thing after a day or 2.
Brother Geoff told me about a couple he has been using for 6 months or more and they really work well on his GV as he has no power were it is stored. The Auto Store here "Canadian Tire" has a special on 40watt units and a 7amp controller. Re' $245 now $99.00+. I checked Amazon .com and they have identical size/make on sale for $190 US so for one of the infrequent times we are actually getting a fantastic deal here. Off I go and get it and now it is fastened to roof with 3M tape with little alum angle legs I cut up. I then wired it to the batteries. It works and as long as some sun or shade happens all should be fine. It cuts in at lower than 13v and off at 14.2v.
I ran the wire to underneath (remove lite first) of right rear clearance lite and thru the hole in rear cap for those wires and sealed it back up..
Here is a picture of it in place.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: solar charging engine batteries

Reply #1 –
John, what's the name of the solar panel?
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: solar charging engine batteries

Reply #2 –
Quote from: rbark –
John, what's the name of the solar panel?

Sonny
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: solar charging engine batteries

Reply #3 –
I went another route to having my engine batteries solar charged.  I have. Bidirectional voltage sensitive relay in place of the diode isolator.  Whenever the house batteries or engine batteries are being charged, all become connected together to receive the juice.  And I have solar on the roof for the house batteries.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: solar charging engine batteries

Reply #4 –

I too have solar on roof for house batteries and everything else we need when travelling, we live off it on the road- no generator running in this place.
The one panel I got for engine Batteries is made for Coleman but it is the exact same one that is on Amazon (right down to the box and pictures)
Amazon.com: Sunforce (38040) Crystalline Solar Panel Kit with Stand: Automotive
I just copied the link and see it is now on at $148, big drop from yesterday but still $70 us more than what I paid here. I see by  the controller that is has Coleman on it so it is the exact same one.
JohnH

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: solar charging engine batteries

Reply #5 –
If you have solar, there  are charge controllers that will do both start and house batteries at the same time and separate. No need for separate panels.
1994 U280, Build 4490
Deming, NM.

Re: solar charging engine batteries

Reply #6 –
If parked away from shore power for any length of time, I just connect a very short jumper from the house to the engine batteries at the bus behind the plastic cover in the wet bay. The big cables come in here so it's only about 2 inches from house to engine battery. Helps to write a note so you remove it before starting up. This way, the solar charges both. Simple connection and costs nothing.

The cables come into the bus at the top left of the attached B2126 schematic.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: solar charging engine batteries

Reply #7 –
I could have just turned the boost switch on to charge both but wanted thebatteries to be getting a steady (not allways I know) charge irrespective of the house.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: solar charging engine batteries

Reply #8 –
Quote from: Twig –
If you have solar, there  are charge controllers that will do both start and house batteries at the same time and separate. No need for separate panels.

This is a great Segway into a question I have wanted to ask...

Installed a new charge controller that has the 2nd isolated output for charging the chassis batteries. It is installed in the L shaped cabinet next to the couch and I am wondering if there is a wire in this area that is live back to the chassis bank?
Chris 1999 U320

Re: solar charging engine batteries

Reply #9 –
The boost solenoid uses a lot of juice and gets too hot to touch after an hour or so. A latching relay would be the ticket as they don't use any juice once triggered. The VW latching relay for the water pump is a good example of a latching relay.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: solar charging engine batteries

Reply #10 –
yandina battery combiner. Does it all. lifetime warranty.
1998 U270 34'

Re: solar charging engine batteries

Reply #11 –
What start battery bank? I start my M11 with the coach batteries and do not have a "start battery bank".
John, I believe you could do the same thing!
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: solar charging engine batteries

Reply #12 –
Wyatt, could I replace my 3 starting bats. on the u320 with 1 agm 8d making a total of 4 and use the boost to charge them all. I have 1200w of solar, classic 150 controller. Turn boost off after start and let engine alt charge the 1 8d. When eng. not running use boost again to charge 4 with solar. Thanks jch
JC
1999 U320

Re: solar charging engine batteries

Reply #13 –
The issue with replacing the 3 start batteries with one 8D may be the dimensions of the battery tray (i.e. not quite room for the 8D.
I built a battery tray to accommodate two 8D batteries or six golf cart batteries (slightly too large for two 8D batteries). I did this to move heavy 8D batteries from behind the driver side front wheel, to behind the passenger side rear tires (where start batteries were). The passenger rear tires carried less weight than the driver rear tires, with driver front heavier than passenger front. I put heavy things (tools) in passenger side rear basement storage.

I use three 8D batteries (two AGM and one Gel with amp hour meters on each battery). Four 8D batteries will only be better than three 8D batteries if you normally use more than 100 amp hours at night.

I run my refer on the inverter when driving. Charging just the start battery during driving will result in discharge house batteries at the end of the day.

When I intend to start the M11 before there is enough sunshine to start charging, I must limit night time consumption to 50 amp hours. At 75 amp hours used, M11 will start if ambient temp is above freezing. At 100 amp hours used, M11 will not start. Twice, I have had to jump start from car battery.

Why do you use boost for starting? If house batteries are discharged, they will draw heavily from start batteries and reduce amps available for starting. I suggest, when dry camping, to start on start batteries and leave the boost on when driving to charge all batteries.

Note that start batteries used for "deep cycle" will have a very short service life. Deep cycle battery used for starting will only have half the amps available for starting that the same sized start battery will have.

Note also that the boost solenoid uses about an amp of current, so will use perhaps 15 amp hours over night.

With 1200 watts of solar, you could with careful monitoring of amp hour consumption, do what I have done for about 8 years - no start battery bank, no boost switch.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada