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Solar factory prewiring run?

For my continuing education, on 2003 to 2005 Foretravel U320 with factory solar prewiring, does anyone know how the wires are run, and gauge of the wiring?  If the factory wire gauge is insufficient for modern high watt systems (say 600 watts), is it attached internally, or possible to hook new heavier gauge to existing wiring, and "pull" the heavier gauge?  This question is for coaches with the 3 8Ds in the middle of the coach.

Anyone been there done that?
Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Solar factory prewiring run?

Reply #1 –
I didnt know they had any wires pre ran.. where would we find them?

Re: Solar factory prewiring run?

Reply #2 –
My understanding is that it was a factory option.  So only some coaches will have it in place. 


Quote from: DavidS –
I didnt know they had any wires pre ran.. where would we find them?

Dan - Full timing since 2009
2003 U320 40' Tag 2 slide

Re: Solar factory prewiring run?

Reply #3 –
Mine has a breaker for solar, but I saw no wires for it. This isn't the easiest coach to pull wire in.
Dave W. (AKA Toyman )
'03, 270, 36', Build 6095, Pulling whatever I hook it to.

"Don't cry because it's over. Smile because it happened."
Dr Seuss

Re: Solar factory prewiring run?

Reply #4 –
Our coach has the factory solar stub-out. It must be factory, since the red and black 10AWG wires are integral with the harness from the pilot overhead storage to the front of the curbside floor wiring chase.

From the roof down:
Roof entry location. (pic 1)
Hole with wires going into a roof rafter. (Pic 2)
Wires/loom entering interior through hole in bottom of roadside roof rafter, just forward of TF slide locking cylinder. (Pic 3)
Going to the front OH console above pilots seat. (The loom between the aluminum extrusion and steel truss over the slide opening. (Pic 4)
Down the vertical wire chase behind pilots seat, and through the floor. (Pic 5)
Out of the floor above LF wheel, and into the cross member, heading to curbside*. (Pic 6)
Out of cross member and into interior curbside chase below copilot cup holder*. (Pic 7)
From there, the wires go through the curbside floor chase and enter the basement in bay 2, just behind the first intermediate bulkhead and above the inverter. (No pic) The wires had been cut there.
*Note: Factory wiring is loom my finger is on. Others are not factory.

Greg

 

Greg & Cathy
2000 U320 4010 DGFE Build #5650
Had: 1999 Tradewinds 7370

Re: Solar factory prewiring run?

Reply #5 –
Maximum current capacity for 10 gauge wire is 30 amps according to the national electrical code, NEC, so this limits your solar capacity.  You may want to pull new wire anyway. I had no problem pulling the solar wire.  I would recommend using using 4, or 6 gauge wire, depending on your system requirements and future needs.  I make a recommendation to go up a size from your current needs, to make room for expansion.  I bought all my wire, junction box, breakers, solar panel hold downs from AM Solar, and they will help size your system.

It took me only two years to want to go from 560 watts to 1200 watts.  That was after going 14 years with only 150 watts.  So much depends on your needs.  No use wasting $$$ with too large a system, or too small a system, that you will upgrade in the future. 

Solar Cable Gauge Calculator

RV Solar Panel Kits & Camping Solar Panels, Batteries & Chargers: AM
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: Solar factory prewiring run?

Reply #6 –
30 amps at 120 volts is 3600 watts, so if you run series or series parallel to raise your voltage, no problem. I am running one 960 watt string at 120 volts, this is only 8 amps on 10 gauge.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Solar factory prewiring run?

Reply #7 –
The practical maximum is 4 panels and around 1300 watts on a 36 foot 102" coach. The 40s may, depending on roof layout, take one more panel. The panels are so cheap now that you only have to add $150 maximum for an additional panel.

I just bought a couple of $25 Siemens 12V panels to make into two chargers for my tractor and car I don't drive much. This is in our home town and you can see they have hundreds of panels from new to a couple of years old. It's estimated 500,000 panels are thrown away each year. Too bad as they loose very little efficiency even at 10 years old. New panels are producing more watts per panels so the older ones are becoming obsolete.

Example in Grass Valley: Selling solar panels for charity - general for sale - by owner These are the same size commercial panes as the ones we have on our U300 but our panels are 10 years old now and 285 watts so I could replace ours for $500 and get about 200 watts more.

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

Re: Solar factory prewiring run?

Reply #8 –
Do all or most FT's have this factory wiring?
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Solar factory prewiring run?

Reply #9 –
Quote from: folivier –
Do all or most FT's have this factory wiring?
None of the four I have had did. My 2003 has a self resetting breaker labeled "solar", but no wires running to it, so assume the wiring  was a factory option. I had to run two duplex 10 gauge marine wires down behind fridge to battery bay.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Solar factory prewiring run?

Reply #10 –
Quote from: jcus –
30 amps at 120 volts is 3600 watts, so if you run series or series parallel to raise your voltage, no problem. I am running one 960 watt string at 120 volts, this is only 8 amps on 10 gauge.

I like your comment, however I am having trouble thinking of equipment in todays market that I would buy and mount on my rv, giving 3,600 watts, let alone just to save having to rewire from the roof.

I did a similar system to yours, yielding 1187 watts on the roof with 4 older design 60 cell panels.

The math was as follows.  Max power of 335 watt panels 34.1 (max power volt, VMPP) x 2 = 68.2 V x 9.83 (max power current, MPP) = 770 watts.  LG 280 31.9 volt x 2 = 63.8 v x 8.78 = 560 watts.  In parallel 63.8 volts (lower of two parallel voltages) x 18.61 amps (combined amps) = 1187.31 watts from my roof system.  My 100 amp, 150 volt solar controller is rated for 1400 watts in a 12 Volt system, thus I ended up with the above 1187 watt system.

Solar Battery Charging
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: Solar factory prewiring run?

Reply #11 –
Quote from: Jack Lewis –
I like your comment, however I am having trouble thinking of equipment in todays market that I would buy and mount on my rv, giving 3,600 watts, let alone just to save having to rewire from the roof.

I did a similar system to yours, yielding 1187 watts on the roof with 4 older design 60 cell panels.

The math was as follows.  Max power of 335 watt panels 34.1 (max power volt, VMPP) x 2 = 68.2 V x 9.83 (max power current, MPP) = 770 watts.  LG 280 31.9 volt x 2 = 63.8 v x 8.78 = 560 watts.  In parallel 63.8 volts (lower of two parallel voltages) x 18.61 amps (combined amps) = 1187.31 watts from my roof system.  My 100 amp, 150 volt solar controller is rated for 1400 watts in a 12 Volt system, thus I ended up with the above 1187 watt system.

Solar Battery Charging
I run two strings each with its own solar controller and 10 gauge feed. First is three 72 cell panels with a VOC of 40 volts in series. So 960 watts at around 8 amps at 120 volts. The second string is three 160 watt panels  in series at about 22 VOC per panel. So about 7 amps at 66 volts. All in theory though, never see it that actual amount. Agree 3600 watts is not very likely, but did read about one guy that had  2400 watts, but think that was a 5th wheel with basement air. Some of the new solar controllers are good for 250 volts now, so possible to run 5 big panels in series.
Victron Energy SmartSolar MPPT 250/100-Tr Solar Charge Controller w/ B
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Solar factory prewiring run?

Reply #12 –
Not really, although this is called a 100 amp 250 volt controller,  in a 12 volt system it is only rated for 1450 watts, the same as my 100 amp, 150 volt controller.

"Victron Energy SmartSolar MPPT 250/100-Tr Solar Charge Controller Specifications:

Battery Voltage: 12V/24V/48V Auto Select (software tool needed for 36V)
Rated Charging Current:  100A
Maximum PV Short Circuit Current:  70A
Maximum PV Open Circuit Voltage:  250V
Nominal PV Power (12V System):  1450W"

Quote from: jcus –
I run two strings each with its own solar controller and 10 gauge feed. First is three 72 cell panels with a VOC of 40 volts in series. So 960 watts at around 8 amps at 120 volts. The second string is three 160 watt panels  in series at about 22 VOC per panel. So about 7 amps at 66 volts. All in theory though, never see it that actual amount. Agree 3600 watts is not very likely, but did read about one guy that had  2400 watts, but think that was a 5th wheel with basement air. Some of the new solar controllers are good for 250 volts now, so possible to run 5 big panels in series.
Victron Energy SmartSolar MPPT 250/100-Tr Solar Charge Controller w/ B
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: Solar factory prewiring run?

Reply #13 –
On the 250 volt unit, you could run five 280 watt panels or five 300 watt panels, not very likely to develop the full 1500 watts. Victron did tell me though, that its solar controllers will limit amperage to protect itself.
But I believe it's more for people who because of space limitations, run smaller panels. Ten 100 watt panels in series, would be 1000 watts at around 200 volts.
Or for the increasing popular 48 volt systems using a leaf or tesla battery, where it can handle 5800 watts of solar.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.