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It's a tricky one. I have the same panels as you, and the same charge controller, but I wire mine in series most of the time. There's a chance I'll fry my charge controller from a spike on a cold morning, but I've had my setup for a year and that hasn't happened yet. So you *should* wire them in parallel to avoid having to worry about that issue (or get a 150 volt charge controller).So for this set up what is the better bet then to go parallel? Only big reason I like parallel is the fact of not loosing all your panels if somehow there was a problem with wiring, panel maulfution or shaded ect..
And the charge controller you linked to is the same unit I use and love. Looks like $219 Canadian = $165 U.S., so it's the same price too. Get the remote monitoring box too (it's at the bottom of the link you sent), it's very nice to have and is a better display than on the unit itself.
For the inverter, as Mike pointed out the 600 watt Xantrex ProWatt should be able to handle the surge from your fridge turning on, so it should work fine.
That inverter will have plenty of power left over to power other AC gizmos.
As far as the remote switch, it's just to turn the inverter off and on. Personally I don't really use it since I just leave the inverter on 24/7/365 even when I'm not using my RV, but it's handy if you plan to and won't have easy physical access to the inverter:
https://www.amazon.com/Xantrex-808-9.../dp/B002W87JNO
While technically the 640 watts of panels could be sending extra power to the charge controller, in practice I've found that two flat mounted 320 watt panels only put the charge controller on max 40 amps for part of the day. And that's no big deal, the charge controller just dials back the output, nothing bad happens.You would be over powering it and absolutely no room to grow if needed.
As far as no room to grow, while it would be nice to have a 60 amp charge controller, it's quite a price jump, since 60 amp MPPT charge controllers start around $575. That's pricey for an RV install. If someone has a link to a cheaper 60 amp MPPT charge controller, please share it.
And I've found 40 amps to be plenty strong. It's far more power than 99.99% of all RV solar install have, for example.
It's about $43 extra, which is a whole lot cheaper than a charge controller capable of handling three 60 or 72 cell panels in series.The moment you add a 3rd panel in parallel now requires very expensive combiners and fusing.
$11 for the 3-way combiner:
$32 for three inline fuses:
Last edited by Wrybread; 06-05-2017, 12:24 PM.Comment
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While those combiners and in line fuses work they can be difficult to replace or they can get corroded from the moisture in the air.
It's a tricky one. I have the same panels as you, and the same charge controller, but I wire mine in series most of the time. There's a chance I'll fry my charge controller from a spike on a cold morning, but I've had my setup for a year and that hasn't happened yet. So you *should* wire them in parallel to avoid having to worry about that issue (or get a 150 volt charge controller).
And the charge controller you linked to is the same unit I use and love. Looks like $219 Canadian = $165 U.S., so it's the same price too. Get the remote monitoring box too (it's at the bottom of the link you sent), it's very nice to have and is a better display than on the unit itself.
For the inverter, as Mike pointed out the 600 watt Xantrex ProWatt should be able to handle the surge from your fridge turning on, so it should work fine.
That inverter will have plenty of power left over to power other AC gizmos.
As far as the remote switch, it's just to turn the inverter off and on. Personally I don't really use it since I just leave the inverter on 24/7/365 even when I'm not using my RV, but it's handy if you plan to and won't have easy physical access to the inverter:
While technically the 640 watts of panels could be sending extra power to the charge controller, in practice I've found that two flat mounted 320 watt panels only put the charge controller for part of the day. And that's no big deal, the charge controller just dials back the output, nothing bad happens.
As far as no room to grow, while it would be nice to have a 60 amp charge controller, it's quite a price jump, since 60 amp MPPT charge controllers start around $575. That's pricey for an RV install. If someone has a link to a cheaper 60 amp MPPT charge controller, please share it.
And I've found 40 amps to be plenty strong. It's far more power than 99.99% of all RV solar install have, for example.
It's about $43 extra.
$11 for the 3-way combiner:
$32 for three inline fuses:
Like anything else. You can get away with going cheap up front but end up paying more in the end if there is an issue with the cheap stuff.
The decision is up to each person to make.Comment
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I know they should work. I have both the dual and triple type connectors but some are not made as well as others. If not protected water can get inside to the connection point.
You also have to be careful if you need to replace the fuse on the in line holders. Those connectors can come lose if incorrectly pulled apart or if it is done during the day time with sunlight can cause an arc flash.
I am just trying to tell people to be cautious when using certain equipment. It only takes one act of complacency to hurt someone with electricity.
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You just admitted you are doing it incorrectly, giving bad and dangerous advice. No other way to spin it.
Urrbanelite if you do not listen to me, then listen to SunEagle, he is telling you the same thing I am. Wyebread is cutting corners and playing with fire pushing the limits. There is no reason you need combiners or fuses between the panels and controllers if you do it the right way. Spend the extra few dollars on equipment made to do what you want and need safely.
Here is the bottom line. I am giving you the same advice I would advise any client. I am a licensed professional engineer with over 300 Off-Grid design/builds in both commercial and consumer residential systems. I am personally responsible for each design. If anything goes wrong like a fire, structural failure, I am solely responsible and liable for my work. I am giving you the same advice I would if you were paying for it. Wyebread is playing fast and loose with numbers he does not understand. He cannot guarantee his work or be held liable.
So here is some things you can consider to work with. If you go with the Rolls S-550 batteries, 2 in series, Ri of roughly 5 milli-ohms which means they can easily handle up to 1000 watt Inverter and be charged with up to 80 amps maximum. They need a minimum charge current of 45 amps to keep them healthy. Batteries and charge currents must be matched to work with each other.
You are going to want a quality Mobile Inverter/Charger, and I highly recommend you buy one that has a built in battery charger, and AC Transfer Switch so you can use shore power to charge your batteries and preform monthly equalization. Additionally if you have shore power, you will not need the solar or batteries. When on Shore Power all your loads will come form shore power and your batteries get topped off by the charger. Just about every factor RV comes equipped with an Inverter/charger with AC Transfer switch. Those Rolls batteries are expensive and you want to protect them. So here are just a couple Inverter suggestions that will fit your needs.
Xantrex Freedom HFS 1055 a 1000 watt model with AC Transfer Switch and 55 amp charger.
Magnum MMS1012 G a 1000 watt Inverter with AC Transfer Switch and 50 amp charger.
As for wiring diagrams I already gave that to you earlier. Actual fuse and wire sizes will depend on that equipment you will use. Regardless the wirring diagram does not change.
One last word on Charge Controllers. Look at a Morningstar TS-MPPT-60. They have a Voc input of 150 volts, max input of 800 watts, battery can be 12 to 48 volt battery, Surge Suppression, and fully listed with all listing agencies including UL, ETL, cETL, CE, SAE and compliant with NEC. Yes it cost more, but will allow you to save on wiring, fuses, and combiners to pay for itself. Not to mention you will sleep better at night not pushing limits.Last edited by Sunking; 06-05-2017, 01:28 PM.MSEE, PEComment
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I purchase pre-terminated cable as well. I've been buying (and recommending) this seller on Ebay. 2 x 20 ft for $27, or 10 ft for $19. Different reasons to prefer Ebay vs Amazon sometimes, but the cables and terminations appear to be good quality.CS6P-260P/SE3000 - http://tiny.cc/ed5ozxComment
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As far as protecting the joiners, what I do is leave a little space under my solar panels to store it. Since the panels are flat mounted it stays completely dry. Well, mostly.Comment
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Poor Grandpa Abe, always misinterpreting things and flying off the handle. If you'd have included my next sentence in your quote of mine you'd see that I specifically recommended he not wire in series:
"So you *should* wire them in parallel to avoid having to worry about that issue (or get a 150 volt charge controller)."
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I agree that your action will protect the connectors as long as they don't sit in any standing water. The problem with using in-line fuse holders is that they need to be accessible which usually means not stuck inside or under a fixed overhang.
While my connectors are under the panels my combiner box is NEMA 4X and is relatively easy to access and change out the fuses. It will cost more then using in-line fuse holders but IMO it is a better installation.
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Wrong dead wrong. The chart only apples to 12 volt battery circuits. You do not know what you are talking about.Here's a handy chart for figuring your wiring:
Use the 3% loss column of the graphic.
If you wire your panels in parallel, that's 640 watts @ 36 volts = 17.7 amps (640/36 = 17.7)
In series, that's 640 watts @ 72 volts = 8.8 ampsLast edited by Sunking; 06-05-2017, 02:38 PM.MSEE, PEComment
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For connectors I highly suggest you cut off the MC4 connectors and use sealed Anderson connectors. Completely weatherproof and waterproof. Connect and forget it. 3-Pole Mini SPEC Plant are made for RV's and Boats along with 4-pole if you intend to parallel panels. You can buy them and premade cables to any spec from Powerwerk.Last edited by Sunking; 06-05-2017, 02:48 PM.MSEE, PEComment
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