RV 30a power and adding a panel

kayenta

Okay so I have a travel trailer that is hooked to a camp 30a electrical to a box with a fuse switch on a panel box. I have a battery that has a factory hook into the trailer electrical which has an inverter I've never seen. Can I use the electric and a 100w panel at the same time? Or do I need do something? Lol

Cariboocoot

Re: RV 30a power and adding a panel

Welcome to the forum.

Okay what you're wondering about is whether or not you can use a 100 Watt solar panel to charge the battery at the same time as the shore power is charging it.

The answer is "yes".

Both will charge with regulation based on Voltage; they won't interfere with each other (although they may disagree).

Don't expect much charging from a 100 Watt panel, though; it will be about 5 Amps.

kayenta

Re: RV 30a power and adding a panel

Oh good. It's really to run a sewer macerator. The auto correct typed spelled moderator. Lol. Sorry. But yah what's a good rating panel to use as a starter. That won't interfere with my shore or camp power. At what point will they bang heads.

Cariboocoot

Re: RV 30a power and adding a panel

They won't ever "bang heads" so long as both charge sources are regulated.

What you want to determine is the capacity of the battery you're trying to charge: Amp hours @ the "20 hour rate". Then see if you can find the info on the RV's "converter" which is supplying charging while the shore power is connected. You want to avoid having both together feed more current to the battery than it is capable of accepting, and that will depend on its capacity and type.

kayenta

Re: RV 30a power and adding a panel

Excellent. That's something I can do. Thank you so much for your help. I'm sure I will have more questions quickly!!!

icarus

Re: RV 30a power and adding a panel

Moderators often find themselves in the sewer!

Welcome to the forum,

Tony

kayenta

Re: RV 30a power and adding a panel

Okay you guys. So instead of marking up a new thread, I managed to find the one I last started and this question is the next step for me. I hooked up my original 100W vmp 17.5 21.7 v 6.21a to a 1000w grid tie inverter, vmp 18-21v voc 20-24 mmpt range dc 15-23.

Now I have my 2nd panel. I've tried to hook it up both in series and in parallel both to the grid tie or the solar/wind regulator which I think is a 600w if I remember correctly. Neither the 600 or the 1000k worked either in parallel or series. The grid tie stopped blinking and it looks like in the sun, trying to squint that both red and green lights are solid on. doesn't sound like working. The other I hooked up with the battery on it, and it says my battery is over charging on both counts.

So clearly I"m out of my league. LOL Can someone help?

Oh and the 2nd panel is 100w 21.60 volts, 6.32 amps, 17.40 volts

westbranch

Re: RV 30a power and adding a panel

I don't know anything about Gt so as to the regular PV charge controller, it will not charge a full battery. Have you checked its Voltage? if it is above 13.2 volts, the message is correct.

kayenta

Re: RV 30a power and adding a panel

well I thought it was supposed to cut it off the charging to the battery, but it just keeps blinking like it doesn't like being hooked up. lol

westbranch

Re: RV 30a power and adding a panel

depends which CC it is , it may just be in float stage and that is what the CC is telling you.... which CC is it?

kayenta

Re: RV 30a power and adding a panel

it doesn't say. lol, that part was the present. mppt. japanese i believe. its wind and solar, battery with a DC out for lights

one panel everybody is happy. add the panel and no one wants to register a charge. I tried it in series, and it shot out the roof volt wise, obviously because the panels are both 20's. but I thought the voltage was supposed to stay the same for parallel. . the video's make the 2nd panel look easy. lol

so if its in float, do I just wait and come back later? lol, or its just floating and leave it alone? i haven't seen if there's an out to the light source yet tho. i'm needing some more wires.

BB.

Re: RV 30a power and adding a panel

Sounds like the second panel is hooked up "backwards" and shorting out the input to your controller. Check with a volt meter and make sure that second panel is connected + to + (and - to -) on the controller.

In full sun, what is the Vpanel-input voltage to the controller? One panel? Both panels?

-Bill

kayenta

Re: RV 30a power and adding a panel

BB. wrote: »

Sounds like the second panel is hooked up "backwards" and shorting out the input to your controller. Check with a volt meter and make sure that second panel is connected + to + (and - to -) on the controller.

In full sun, what is the Vpanel-input voltage to the controller? One panel? Both panels?

-Bill

They are both reading at the 20-21 v levels separately so maybe together they are pushing 40's? not sure I can't use my volt meter beyond the 9v setting LOL. That helps doesn't it. Definitely I need to revamp my wiring from the exposed wires, and match the gauges here. Because its really like you said, it feels like its transposed but then it reads fine in positive and negative according to the manufacturer's labeling. I taped them positive negative. So I use the solar extension wiring with one end bare wire. When I had them in series they were jumping around. But I thought having a 1000w inverter could handle two or more 100w panels. If I get them both to work on the grid tie I'd be happy. I'm not 100% invested in the charge controller just yet. I realize that I have to read the manual. Heavens to betsy. I can't believe I'm having to break down and read a manual. Talk about spoiled, I ran as quickly as I could to the forums. hahaha. I'm still waiting for a proper parallel connector I will say. I am just wiring them both to the grid tie, which I thought I could do thanks to youtube. hahaha. pathetic huh. i feel like a solar failure.they say its okay to wire negative to positive and positive out one panel, negative out the other panel. Then the other way is both positives, on one side and both negatives on the other. that's what I did I thought. The wires don't change the polarity right? I mean I don't think that's possible. I was wondering if the panels both being in the 20's is too much for the grid tie?

I just now managed to hook one panel to the grid tie, one panel to the charge controller. Then I took the out from the charge controller for the light output, and hooked a positive to the grid tie, and it reads great. but there's still no volt reading on the controller. but it reads in the output. so I will check the settings options and see what that says. maybe the grid tie doesn't blink when there's two panels like it does when there's one?

BB.

Re: RV 30a power and adding a panel

kayenta wrote: »

They are both reading at the 20-21 v levels. Definitely I need to revamp my writing from the exposed wires, and match the gauges here. Because its really like you said, it feels like its transposed but then it reads fine in positive and negative according to the manufacturer's labeling. I taped them positive negative. So I use the solar extension wiring with one end bare wire. When I had them in series they were jumping around. But I thought having a 1000w inverter could handle two or more 100w panels. If I get them both to work on the grid tie I'd be happy. I'm not 100% invested in the charge controller just yet. I realize that I have to read the manual. Heavens to betsy. I can't believe I'm having to break down and read a manual. Talk about spoiled, I ran as quickly as I could to the forums. hahaha. I'm still waiting for a proper parallel connector I will say. I am just wiring them both to the grid tie, which I thought I could do thanks to youtube. hahaha. pathetic huh. i feel like a solar failure.

I am getting really confused here...

GT Inverters are one thing... And no batteries involved.

Charge controllers are something else.

The sewer macerator will work fine if a GT inverter is working or not.

An Off Grid inverter that has failed, or is too small to run the pump (or if the battery bank is too small), you will have problems.

Note that a 1,000 watt GT inverter will probably have 25 watts of "tare losses" just to turn on. A 100 watt panel may only generate 50-75 Watts of AC power output to the grid for the 1kW GT inverter.

-Bill

kayenta

Re: RV 30a power and adding a panel

so are you saying that if we just focus on the grid tie inverter. I should be able to tie both panels either series or parallel, without worrying about the little light? lol or will they cut out if they go over 48 v together.

and the macerator issue is wonderful now just with the one panel I do keep the battery nice and level. and outside of the grid tie yes. maybe my problem is worrying about the blinking light on the grid tie. i know that sounds less than technical. it must be about being confident that its working but not seeing it read on the controller, was a bit confusing. But you were saying that it might just be the controller readings. And testing would go to the next level for those questions.

but I'm so shocked that I've entered an era where hooking positive to negative would be a part of my life. And the positive to positive negative to negative I'll test again tomorrow, with hopefully the Y connector.

and I don't see in my internet reading, I've tried to search the usual hookup for two panel systems where anyone hooks two panels, but they seem to all work when someone else does them. lol. i found the manual for the charge controller. its called excellent controller of all things. so it does say that its a 12v 24v system. so each one panel being 24v means that I have to hook these in parallel right, my amps should be good, since the grid tie says, its rated for 60 amps. it looks like the grid tie is just a high watt sales thing. because it doesn't seem like I'd be able to add more panels in a 28v system, unless I retry the parallels with the y connectors, and make sure that the wire gauge is good. Is that logic that is acceptable for this type of set up?

and for the charge controller, I need another battery to match the voltage which you guys said earlier. so that would account for some of the variables. the manual does say there's a day and night mode. I think even though I was in day mode, that aspect may have been a settings issue. so right on all counts. and I was wrong to think I could hook in series in this particular set up because of the volts and not the amps. and I was confused because I thought the amps were the problem, and the escalating volts, without the battery addition was likely a cause for jumbled readings. yes, so I was trying many things at once. lol. and yah that makes sense now. if you guys hadn't mentioned it, it wouldn't have caught my eye at all in the manual. it didn't the first time I read it. so it makes more sense. not sure what happened with the grid tie though, but a solid parallel without getting frisky with a series, with everything set properly might win me some better results.

BB.

Re: RV 30a power and adding a panel

No.... I am still confused... A GT inverter (typically) has nothing to do with batteries. It just take DC power in and outputs 120 or 240 VAC to the utility grid (if the utility power has failed, then the GT inverter is shut down too).

A solar charge controller (like in your picture)--Connects between your solar array and the battery bank. It's job is to make sure that the battery is not over charged once it is full (basically, the charge controller just turns off the connection to the solar array).

12 vs 24 volts, wind turbines, etc... Is all causing more confusion (I think). We need to get back the basics.

You have a 12 volt (?)? battery that is connected to a 120 VAC off grid inverter that powers the pump?

And you have 1-2 solar panels going through the solar charge controller directly to the battery bank.

It appears you can also take 12 volts from the charge controller and send it to the AC inverter (this is usually not a good idea, most solar charge controllers with LVD--low voltage disconnect--cannot handle the DC input current for an AC inverter and may damage the solar charge controller.

Can you give us a link to the charge controller, tells us the Amp*Hour and voltage of your battery bank? etc...

-Bill

kayenta

Re: RV 30a power and adding a panel

Okay, the charge controller, is being attached. I'll try and attach a print to pdf for the grid tie.

I do understand about the separation issues between the grid tie and the controller. You are completely on point.

The battery is a NAPA 8302 marine deep cycle 24v, 686 cranking amps.

I think I realize now that I blew it with a series connection. I think my readings were off as I was switching around scenarios back and forth like you were saying, as the various units were resetting and unsetting. I can't seem to find out if the grid tie blinks or doesn't blink, I thought I read it was supposed to blink when functioning properly, but it does have a warm up set up stage like mentioned earlier.

My guess based on the comments thus far, is parallel. Am I supposed to have 10 gauge as the average wiring size?

the manual says there's a night mode. and that shuts off the external light panel. okay so yah, there's some deep functional shut offs within the controller. for the lights. right. but it looks like if I choose mode C or D, i'm somewhat better off. you are saying too its not a good idea to optimally feed the 12 v out on the solar controller, for lights, to any grid tie inverter. yah I was somehow thinking the already working 12v to 28 v won't mean much but it will you are saying in some conditions. i'm better off with a straight run and possibly a cross connect to the solar controller for the battery charge, in my mind. but I'm not going to form a hard opinion until after you guys give the cross exam on it. lol

kayenta

Re: RV 30a power and adding a panel

it also looks like i might have to manually set 48v, if anyone reads this with me. on about page 18, I think is where I didn't realize that I might have to set it to 48v. So it can take 48, from two panels, but on the 3rd panel I would have to shift the set up from adding the volts. so then if I went through every little step, to make sure the settings conform then I would likely get different readings, because despite the 48v rating, it might be set to 12. yah so the first few comments were right on.

BB.

Re: RV 30a power and adding a panel

It does not appear you need to program anything for 24 or 48 volt max solar panel... It may be just a 12 volt battery can only take a (standard) Vmp~18 volt panel and a 24 volt battery can take an Vmp~36 volt panel.

It is unclear, but that is the way I read it.

Your GT inverter is normally just connected to a solar panel/array and plugged into the AC mains--Will pump power into the AC mains and reduce your home's loads or possibly turn the meter backwards (depending on meter and your utility's rules/regulations).

The manual did show connecting the GT inverter directly to the battery bank... It did not say how it would work/regulate battery state of charge... Don't know. The GT inverter may "turn on" when the battery is charging--But it does not say how any of this works together. I would suggest you do not use this configuration. It may just end up killing the battery from improper charging.

-Bill

kayenta

Re: RV 30a power and adding a panel

Okay I went through my receipts for the panels. It appears the first panel is a 12v. If the 2nd panel is rated 24v will this be the potential problem? Can you have one 12v and one 24v 100w panel hooked together? I was confused because I thought I rated the 2nd based on the specs on the first. But the one that was sent was 24, and the one listed was 12. So I purchased a 12v, I'm relieved. And I'm wondering if I'm either going to have to return or keep both panels separate, or will it be an issue.

mike95490

Re: RV 30a power and adding a panel

maybe. If both panels have the same AMPS rating , you could wire in series, have ~40V, and use a MPPT controller to charge at 95% efficiency, instead of ~75% with PWM.

kayenta

Re: RV 30a power and adding a panel

yah they are about 5.75-6.32 amps each. yah I do have the mppt. so if I went parallel it would impact the volts right? so two 100w series would be about 10-11 amps is that what I'm looking at theoretically. and they would both be at 12-17v?

westbranch

Re: RV 30a power and adding a panel

No, what Mike is getting at is you will get an output at the lower amperage, 5.75A, of those panels and a sum of the voltage ~ 36V Nominal.

vtmaps

Re: RV 30a power and adding a panel

westbranch wrote: »

No, what Mike is getting at is you will get an output at the lower amperage, 5.75A, of those panels and a sum of the voltage ~ 36V Nominal.

Just to amplify what Mike and westbranch wrote:

When you put panels in series the voltage adds up, but the current is limited to the lowest of the panels in series. Thus your 6.32 amp panel will be reduced in its output to 5.75 ÷ 6.32 = 91% of its 100 watt rating.

When you put panels in parallel the currents (amps) add up if the panels have the same voltage. Rule of thumb: when putting panels in parallel, the voltages should match within 10%.

--vtMaps

kayenta

Re: RV 30a power and adding a panel

Okay so since one panel is 12v and one is 24v, you are saying that series is the better option because of the lower current for the amps? Because my grid tie can handle the amps added together its a 30amp. 60a max @1000w, looking at it now its says max input range 28v, and mppt v at 15-23. So that's why lower current for the amps.

. So, hooking the 12v/24v panel is doable if I hook in series, I won't take out the world with 1000w grid tie. Because the amps will be held down by the mppt. The guy who I bought it from insists that its 12v, despite the box saying 24. Then he must be right. Does that mean my other panel will max at 24? because in this AZ sun that might be way cool.

Update: I tried it in series, and it seemed like the grid tie stopped. So I'm not sure, it seems like regardless with two panels it should work either way. I haven't tried parallel, i'm waiting for my Y connectors still. Parallel seems to work in theory. If both panels 100w, both are approx 12/24v and both are 5-6amps.

I think I outdo my grid tie in series overage on the 48v. I haven't seen it go over 40 but I don't know why else series wouldn't work.

BB.

Re: RV 30a power and adding a panel

Can you give us the panel ratings/find a vendor name/part number?

Can you count how many cells there are in the panel... Standard panels can have 36, 60, 72, etc... That can help us with the voltage.

And/or measure the Voc (open circuit voltage) of each panel under sun with a volt meter.

If you can take a DMM set to 10 amp full scale current and and measure the short circuit current (Isc) for each panel. Just set them next to each other in full sun (same angle, measure Isc about the same time, conditions) and we can see how close the current for the panels would be.

You cannot just "guess" what the panels are... We really need to know fairly accurately.

-Bill

kayenta

Re: RV 30a power and adding a panel

for the 2nd panel that has the 24v rating, listed as 12v
http://www.amazon.com/gp/product/B00FE45FD4/ref=oh_details_o01_s00_i00?ie=UTF8&psc=1
and the picture of that panels box with the 24v rating

i'll get the other's rating. The other is a WSolar Zhejiuying Solar Co. panel who's sticker came off, and I took a picture of it, but I can't read the picture, and I have to find what my son did with the label. But lemme go out and try to get a reading off the panels now since they both should be in a.m. sun.

kayenta

Re: RV 30a power and adding a panel

Okay, so I'm not a multi-meter person at all, so bear with me.

So for the settings V line with three dash lines under it lol at 1000 switch which the manual says to start with:
Panel 1: 20v
Panel 2: 21v

For the settings V~ at 200
Panel 1: 44.8
Panel 2: 43.9

10a AZ full morning on the panels facing the winter sun.

BB.

Re: RV 30a power and adding a panel

Your first readings make sense.

The second set, not at all.

Based on your first readings, you can place the two panels in parallel just fine.

Regarding the meter--Go and measure the VOLTAGE of your car battery and make sure the meter is accurate. Also, check the meter battery... Weak/going dead batteries can give really strange readings on DMM.

Here is a quick course on how to use a digital multi-meter:

http://mechatronics.mech.northwestern.edu/design_ref/tools/multimeter.html

-Bill

kayenta

Re: RV 30a power and adding a panel

Nice multimeter tutorial. I really needed that.

Okay so parallel it is. I'll be attempting that. I have them separated again. I just might be peaking the vdc on series perhaps at times of the day. Or operator failure. lol.

kayenta

Re: RV 30a power and adding a panel

Okay I found the other solar panel sticker. I managed to get the solar wires, the mc4 Y branch connectors. I put the grid tie inverter into a box in the complete dark. I hooked it all up in parallel, and viola' it looks like its working. I bent my head thinking about whether or not its really working. So I'm waiting for the kilowatt meter to know for sure. Series its just not working, at the middle part of the day since I guess the volts skyrocket. But parallel is working. So if I add another panel in parallel I hope this grid tie continues to take them if I buy a similar panel.