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Where are the Solar Prep wires for the solar panels in a 390MP

Hi all

I saw the other thread about the location of the wires from the roof on a 310 but I can not, for the life of me, find them on my 390MP. Has anyone looked for and found them? I am about to install solar panels and want to use the pre-wired connections but need to find those blasted wires. Only place I have not looked is the under-belly. I was really hoping I would not need to go there again but it seems that is next.

Any help would be much appreciated.

Marty...............................
 

Jim Beletti

Owner Experience Liaison
Staff member
Marty - I'll ask someone much more in the know than me and circle back here with that answer.
 
Hi Jim

I would much appreciate that. I have not had any luck finding them and am installing solar panels in the next few days.

Marty...............
 

Jim Beletti

Owner Experience Liaison
Staff member
Hi Marty,

I connected with Jim Bonacci and learned the follow as to where on Paradigm product, the roof-mounted solar prep wiring terminates inside the coach.

Below, I'll paraphrase what I have learned.

In all cases on a Paradigm, the wires will terminate in the front compartment (front generator bay), typically through a hole in the bottom, ODS corner of this compartment. What these wire ends look like have evolved over time. All the Paradigms should have a red or orange PV+ and and Black PV- wire.

Typically there are MANY other DC wires/cables and hydraulic/hoses entering/exiting the front compartment. The wires from the solar prep will be either 10ga or 8ga depending on when the unit was produced.

If it's an earlier unit then it will be 10ga and a rectangular, red, in-line fuse holder should be present there as well and the wire ends in pre-crimped ring terminals.

If it's a more recent unit, there will simply be raw wire ends with no connectors present, again either in 8ga or 10ga red or orange(+) and black(-) wires.

NOTE: There was a short period of time when Plant 2 produced Paradigms were getting their PV+ and PV- hooked to the aux post of one of the mini breakers and the negative cable to chassis ground.
 
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Hi Marty,

I connected with Jim Bonacci and learned the follow as to where on Paradigm product, the roof-mounted solar prep wiring terminates inside the coach.

Below, I'll paraphrase what I have learned.

In all cases on a Paradigm, the wires will terminate in the front compartment (front generator bay), typically through a hole in the bottom, ODS corner of this compartment. What these wire ends look like have evolved over time. All the Paradigms should have a red or orange PV+ and and Black PV- wire.

Typically there are MANY other DC wires/cables and hydraulic/hoses entering/exiting the front compartment. The wires from the solar prep will be either 10ga or 8ga depending on when the unit was produced.

If it's an earlier unit then it will be 10ga and a rectangular, red, in-line fuse holder should be present there as well and the wire ends in pre-crimped ring terminals.

If it's a more recent unit, there will simply be raw wire ends with no connectors present, again either in 8ga or 10ga red or orange(+) and black(-) wires.

NOTE: There was a short period of time when Plant 2 produced Paradigms were getting their PV+ and PV- hooked to the aux post of one of the mini breakers and the negative cable to chassis ground.
Thanks Jim

To this point I have seen nothing like you describe so I am guessing it will be in the belly somewhere. Guess I have to go in there to find them. As to the early or late model I don't have any idea what that means. My unit was built in the first week of May 2021.

Marty.............................
 

Jim Beletti

Owner Experience Liaison
Staff member
Thanks Jim

To this point I have seen nothing like you describe so I am guessing it will be in the belly somewhere. Guess I have to go in there to find them. As to the early or late model I don't have any idea what that means. My unit was built in the first week of May 2021.

Marty.............................
Marty - here's how I would do this...

Find all the red/orange and black electric wires passing in/out of the gen bay through that round hole. Trace each red wire from the hole to where it terminates in that bay. Make a written note or drawing of this. Through this process, it may become evident as to which wires are for the solar.

Some of the wires may go to the mini-breakers. Some may go to a stud connector. Some may be loose. Try to identify where each positive wire goes and what it's for.

Don't worry about the super heavy gauge positive wires for this exercise as that's not what you're looking for.

Note: I went through this same process, though I wasn't trying to figure out which were for solar. Anywhere I have ?? are lines I have not spent anytime trying to determine what they're for. That will happen next week. My coach was produced in May 2021.
Beletti - 340RL - OEM DC Wiring - Gen Bay.png
 
Marty - here's how I would do this...

Find all the red/orange and black electric wires passing in/out of the gen bay through that round hole. Trace each red wire from the hole to where it terminates in that bay. Make a written note or drawing of this. Through this process, it may become evident as to which wires are for the solar.

Some of the wires may go to the mini-breakers. Some may go to a stud connector. Some may be loose. Try to identify where each positive wire goes and what it's for.

Don't worry about the super heavy gauge positive wires for this exercise as that's not what you're looking for.

Note: I went through this same process, though I wasn't trying to figure out which were for solar. Anywhere I have ?? are lines I have not spent anytime trying to determine what they're for. That will happen next week. My coach was produced in May 2021.
View attachment 504
Thanks Jim

Yea, I already did that. The only unterminated wire I found in that bundle is a 12-2 duplex wire with a grey jacket. Pretty sure that is NOT the solar wire (certainly hope not anyway). I will have to open up the belly to see where that solar prep wire is and get it routed to the appropriate spot.

Thanks
Marty..........................
 
Well, just spent the last hour or so dropping the belly and there is no sign of any kind of wiring that might be coming from those solar panel connectors on the roof. So either I am blind, those wires are very carefully hidden or they are not there. Unless someone has some other idea of where to look it seems I have to run new wires to install these solar panels.
 

Jim Beletti

Owner Experience Liaison
Staff member
Well, just spent the last hour or so dropping the belly and there is no sign of any kind of wiring that might be coming from those solar panel connectors on the roof. So either I am blind, those wires are very carefully hidden or they are not there. Unless someone has some other idea of where to look it seems I have to run new wires to install these solar panels.
Hi Marty,

Some suggestions...

1. Look at the wire color and gauge of the solar prep, on the roof behind the MC4 connectors. Use that as your guide as to the wires you're looking for in the gen bay.

2. Check for DC voltage on the wires at the prep on the roof. If 12+vdc is detected, then the wires are connected in the gen bay. Start dropping positive wires until you love 12+vdc up top.

3. Similar to 2 above, if no 12+vdc is present up top, consider adding a tone to the wires with a toner, then locating those wires in the gen bay with the toner receiver.
Examples:
- https://www.lowes.com/pd/Jonard-Tools-TETP-800-Cable-Tester-Tone-and-Probe-Kit/5013064439
- https://www.amazon.com/s?k=wire+toner&crid=2WDU7JSLQD010&sprefix=wire+tone,aps,111&ref=nb_sb_noss_1

A toner is a handy tool to have. If you never trace phone, network or coax cables, consider getting the lowest cost unit that has clips for attaching to wires.
 
Well, the mystery has been solved. Solar_Prep.png They never installed the solar prep wiring, just the connector. Someone needs a little more training I think. Luckily I was able to run the PV wires down through the wire way provided next to the tank vents. Since my batteries will be in that area I am actually better off. Still aggravating to find out something that was supposed to be there never was.

Marty........................
 
Another "Hassle Free Upgrade" that is not hassle free. I expected better from Alliance.
In most cases I think they do better, someone on the line had a bad day or missed a step (QA certainly missed it) and I was the lucky recipient of the present. I was able to work around their mistake but I did not enjoy wasting hours of my time trying to find something that was never installed.
 
@MartySchwartz - Sorry to see this. My sense is that this was a production miss. Let us know if there’s some way we can support you on this.
Yea, it was clearly a miss and QA did not catch it.... Don't know if they even check for that. Not much you can do at this point. I am moving the battery bank to inside the conditioned space and the plenum from the roof is directly above where the batteries are going to live so that works out better than trying to use the Pre-wired solar where it was supposed to be. I think I can just cover the hole in the roof from the PV connector with Eternabond tape and call it good.
 

Jim Beletti

Owner Experience Liaison
Staff member
Yea, it was clearly a miss and QA did not catch it.... Don't know if they even check for that. Not much you can do at this point. I am moving the battery bank to inside the conditioned space and the plenum from the roof is directly above where the batteries are going to live so that works out better than trying to use the Pre-wired solar where it was supposed to be. I think I can just cover the hole in the roof from the PV connector with Eternabond tape and call it good
Marty - your plan sounds solid. Clean the area well and if needed, fill the hole in before applying the Eternabond. Once applied, if you have a small roller, roll over the Eternabond to promote good adhesion. Then use some Dicor lap sealant around the edge of the Eternabond. Not required but if you have some, I'd do it.
 
I also have a 390 MP Oct 2021 production. In trying to locate the solar prewire in the battery bay the only wires I thought could possibly be the ones were connected to the battery. I disconnected the wires and did a continuity test to the MC4 connections on the roof and bingo. After hooking up the panels (two series strings of 5 200W in parallel for a 2000W input) I had 104VOC on these wires. When I flipped the breaker on to my Smart MPPT 150/100 the voltage drops to 13.6. I have a 24 volt system installed so will not turn on. Also when I disconnected these wires from my battery my batteries quit charging. So after trying to troubleshoot and solve this problem I am drawing the conclusion the prewiring is somehow tied into the coach DC system. I had contacted Alliance when looking for the termination point of the prewire and they were no help at all as I requested a wiring schematic and was denied. Now I need to either determine how the prewire is tied in or run new wires from the top.

Michael Thompson
2021 Paradigm 390MP
 

Jim Beletti

Owner Experience Liaison
Staff member
I also have a 390 MP Oct 2021 production. In trying to locate the solar prewire in the battery bay the only wires I thought could possibly be the ones were connected to the battery. I disconnected the wires and did a continuity test to the MC4 connections on the roof and bingo. After hooking up the panels (two series strings of 5 200W in parallel for a 2000W input) I had 104VOC on these wires. When I flipped the breaker on to my Smart MPPT 150/100 the voltage drops to 13.6. I have a 24 volt system installed so will not turn on. Also when I disconnected these wires from my battery my batteries quit charging. So after trying to troubleshoot and solve this problem I am drawing the conclusion the prewiring is somehow tied into the coach DC system. I had contacted Alliance when looking for the termination point of the prewire and they were no help at all as I requested a wiring schematic and was denied. Now I need to either determine how the prewire is tied in or run new wires from the top.

Michael Thompson
2021 Paradigm 390MP
Michael - just confirming... You did in fact, in your testing, find that the solar prep wiring terminated at the battery, as in, it was connected to it. Is that what you're saying? Note that Alliance doesn't ship batteries with the unit. Those are generally dealer included/supplied/installed. It's likely the dealer connected your solar prep to the battery.

You also mentioned that your system is 24 volt - I assume that's a system you installed. In this case, your solar prewire will need to go to the input of your MPPT and so long as the MPPT is configured for a 24 volt output, in good sun, the panels should be outputting power to the MPPT and in turn the DC system, "should the battery SOC be a bit lower than 100%".

The Victron Smart MPPT should auto-detect your battery system voltage and set itself accordingly. You may want to dig into the Connect app to confirm the Battery Voltage setting.
 
Hi Jim: After reading some of your posts on here and you mentioned some Paradium's from one production facility had connected the pre-wire to the mini fuse block I decided to do some checking there. So yes the red wire was in fact connected to one of the fuse terminals. The black wire was connected to the negative post on the battery. The other red wire on the positive post was the DC charge wire from the converter. As these wire were all connected in the coach DC system I was gettining continuity at the prewire roof port. That is why I would get the 104 VOC reading after hooking up the panels and 13.7 when I flipped on the breaker for the closing of the circuit to the MPPT. The red charge wire was marked with black electrical tape which is how I was told from Alliance Customer support how the prewire would be identifiable. Also was 6 AWG wire as was confirmed from Alliance. The black wire was 8AWG. The red wire that was connected to the fuse block was also 8AWG. I hope Alliance has done a better job of marking wires left for dealers or installers to locate and install on newer models. It is one of their sales points on how all the wiring is color coded and marked as well as solar access. If not for your information on these posts I would more than likely be running new wires from the roof to complete my system. I am now up and running as it should with the pre-wire.


Michael.
 
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