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Topic: Finished solar! (Read 944 times) previous topic - next topic

Finished solar!

It took longer than I had planned, but the solar is in and working. Many thanks to Roger as I copied his hardware and took his advice. Because of shading where we camp went with all parallel system and large 8 gauge wires to fuse box and 4 gauge to battery hook up even though it was less than a foot from the fuse box to the back of the inverter which has large battery cables going to the connection behind the white panel. Came through the area where the old gas refrigerator vent was, behind the refrigerator, behind the cabinets under the stove, behind sink to the bottom area of the drawers next to the sofa. From there down into the battery box then through the back of the battery box into the AH compartment. Out the top and over to the fuse panel.

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Reply #1 –
Last 3 pictures.

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Reply #2 –
Good job, Chuck.  You will really like what solar does for you.  I was glad I could help, thanks for asking.

Roger

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Reply #3 –
Looks good Chuck!

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Reply #4 –
Congrats Chuck.

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Reply #5 –
Looks good!  Some armchair thoughts: Are you going to put some kind of cover over that wire on the roof?  Unless it has UV resistant insulation, I would be afraid that it would rapidly deteriorate from exposure to sunlight.  Also, I would add protection to the wire any place it passes through a hole - vibration from running down the road can quickly wear through the thin wire insulation if it touches a sharp edge.

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Reply #6 –
Nice installation!
I'm curious about the Smartsolar controller and the data you can extract from it.  I know it gives you info about the amps you're getting from your panels going into the batteries but what data can you get about your batteries state of charge?
IOW do you think it can replace a SOC meter with a shunt?

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Reply #7 –
Quote from: Chuck & Jeannie –
Looks good!  Some armchair thoughts: Are you going to put some kind of cover over that wire on the roof?  Unless it has UV resistant insulation, I would be afraid that it would rapidly deteriorate from exposure to sunlight.  Also, I would add protection to the wire any place it passes through a hole - vibration from running down the road can quickly wear through the thin wire insulation if it touches a sharp edge.
The wire is UV resistant and the coach is only out from under the canopy for a total of 27 days a year. Where the wire passes through the roof I made the hole edge smooth and I will be centering the cable in the other pass-through holes and using expansion foam to hold it.

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Re: Finished solar!

Reply #8 –
Quote from: folivier –
Nice installation!
I'm curious about the Smartsolar controller and the data you can extract from it.  I know it gives you info about the amps you're getting from your panels going into the batteries but what data can you get about your batteries state of charge?
IOW do you think it can replace a SOC meter with a shunt?
This will not give a SOC reading, I use the rule to not let voltage get below 12.4 and didn't want to have to run a shunt wire from the batteries to an inside meter. After I have used this on vacation in June I will know more about it. The coach has been unplugged since yesterday morning and even with the residential refrigerator I had 12.6 volts at 5:30 this morning and now it is going up.

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Reply #9 –
Better quality solar connection cables are designed for outdoor use with or without cover.  They have very heavy UV rated insulation.  Running multiple cables in a conduit or other cover may derate the cable's amp carrying capacity due to heat in a closed conduit. (Ampacity). On our coach very few feet of cable are actually visible as they run under other panels, under the edge of the ACs and other things.  Many ways to do this, your choice.

The Smart series of Victron solar charge controllers adds a built in bluetooth capability so that either or both the bluetooth application can read information from the controller and use a direct connection to a Color Control GX.  While connected to the CCGX data can be saved at whatever frequency you want, reviewed on line and downloaded for use in anyway which you are capable.

Hour by hour data gives you an idea how well your system is working.  Day by day, month by month lets you see what seasonal changes make.  If you keep track of where you are, shade cover and cloud cover, you get to quanitfy those impacts as well. 

Or you can just be happy with what you get and not be too obsessed with the results.

When we are on solar only we rarely get below 75% SOC (based on data we supplied as a starting point). Charging starts early and we are at float by early afternoon.  I am adding a fourth panel (1200 watts total) for better performance in winter.

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Reply #10 –
Yesterday was first full day of using solar, so now I can report results. Generated 4.75 kwh, peak watts was 1040 batteries were on float at 12:30 pm. The bad, tree creates full shade at 3:30 pm down to 50 watts by 5:00 requires 1 hour 20 minutes at 8:30 pm to make enough power to have 12.5 volts in the morning to enable microwave and coffee maker use without using the generator until the next night. We are partially shaded in the morning and at this time 8:30 am producing 440 kwh. I would not benefit from added solar without more batteries to store the power as I am fully charged around noon. I believe our Phoenix Raceway trip in Nov. should not require generator use.
  My coach is power hungry, the residential refrigerator is 8 amps and my DW is watching satellite most of the time due to health issues at this time. I don't have separate inverters yet for ref. and the overhead audio visual. 

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Reply #11 –
Maybe I am just uninformed but the 90% efficient inverters are per the load?  So a smaller inverter pulling 1,000 wats would consume the same power as a bigger inverter pulling the same load.

Or are you telling me a 3,000 inverter is consuming an additional triple the 10% amount between the load and its rating versus a 1,000 watt unit at the same load and the same 90% efficiency?

If a smaller inverter has 92% rating it would seem the 2% difference would be hard to measure!?

A bigger inverter does have bigger cooling fans versus one smaller and ours are variable speed depending on the MOSFET and transformer temps as far as I know.

Like I said I need to be educated exactly how much power that a smaller separate inverter for low loads saves.

If you run smaller wires to it and out of it they would seem to consume as much or more power than was saved?

Never seen double inverters in the past.  Only here.,.

Educimate me.  Running small size coach 12v wiring to change to 120 volt would seem to consume power.

Unless you run big heavy battery cable to the smaller unit?

Seems less loss to move the power in 110 volt?  Not 12 then change it to 110. 

So other than the possible 2 percent improvement on the exact amount of the load minus the bigger cooling fans in our sw2812 it seems not a lot of power savings unless the larger unit consumes 10% more power regardless of a partial load?

Interesting either way. 

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Reply #12 –
My Victron 3000 Multiplus uses 15 watts to operate. Less on standby.  It is 94% efficient and uses 2 pair of 4/0 +/- cables.

My Victron 800 inverter uses 3-9w to operate at 90% efficiency depending on operating mode.  #4 wires from the battery.  It runs the refrigerator and all of the electronics (lots) including all of the device chargers.

The amount of power to operate (have the inverter on) the inverter is not proportional to load.

The difference in operating power between the two inverers is enough to run most of the LED lighting we normally use. If we are not connected to a land line we just shut the big inverter off.

Each of us gets to choose what we want to do for ourselves.  The difference between power to operate inverters is significantly less in the newer inverters.

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Reply #13 –
We are leaving our big inverter off when dry camping but leaving our 800w Victron on 24x7 to power electronics and lots of gadget chargers.

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Reply #14 –
Just trying to understand the basics here.

If a unit is 94 percent efficient then 6% is lost somewhere.  Normally heat as the unit has a cooling fan and different outputs at different operating temps. 

2400 watt at 70degree F. Inverter temp.

1700 watt at 120? F. At the inverter.

If you are using 500 Watts then 35 Watts is being converted to heat. 

Idle power zero load is 20 Watts.

The sw2812 is 3k Watts at 70 degrees F.

Idle draw no load is 30 Watts which matches its higher output capability.

Versus a 2400 watt unit uses 7% of its max rating just to be on I do not think is correct.

That would be 150 Watts to run a tv?  On top of the TVs  actual consumption.

My understanding is that the efficiency loss is for the exact load at the time. 

So a sw2812 states ,like the outback units,  to be 90% efficient.

So at a 800 watt draw the difference would be 4% if the numbers are correct.

One would be at 856  the other would be at 880. 

Running the larger wires to,a secondary inverter would surely lessen any draw from the wire size but I,doubt the loss would be zero. 

24 Watts max difference between a 94% unit and a 90% unit at 800 watt constant draw minus any wire loss would be hard to measure.

Unless the units lose 7% and 10% of their rated just to turn on which I would like to find out.

Using a small inverter might be useful in low output in areas without 120 volt circuits present.

Lots of installation work and money to save maybe 3-4% of the actual load.  If the numbers are correct.

All the current 3k continuous output power inverters by the top brands show 90%.  And are recent models.  Must be 3-4% less efficient to be capable of 3,000 Watts as all the major units rated at 3,000 Watts show the same time 90% versus 2,400 Watts.





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Reply #15 –
Efficiency rating is the conversion efficiency from the 12V to 120V, and doesn't have anything to do with the size of the inverter, or how much ghost/background power it takes to run.

How about an example:

You run a 120V appliciance that uses 360 Watts. That is 3 amps of 120V power from your inverter.  It will need to pull the 360 Watts from your 12V battery.

If that 12V battery was converted at 100% efficiency, it would only pull the 360 Watts you need from the 12V battery, which would be 30 amps of 12 volt battery.  HOWEVER, the process is not 100% efficient, so if your inverter is 90% efficient, it will need to pull:

30 / 90% = 30 / 0.90 = 33.3333 amps of 12V.  3.333 of those amps is lost (yes, mostly to heat) in the conversion process, and the other 30 amps of 12V is converted to 3 amps of 120V to power your appliance.

SUMMARY:
100% efficiency:
30 Amps of 12V  ---->  Inverter ---->  3 Amps of 120V

90% efficiency:
33.333 Amps of 12V ---->  Inverter ---> 3 Amps of 120V and remaining lost during conversion.



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Reply #16 –
One other thing.  Meant to say that your numbers are mostly sound.  You have the right idea, and the math is generally right.  However, it is worth nothing that efficiency is not a SET % for your a particular piece of hardware.  The higher the draw, the lower the efficiency.

So there is additional math element - an 800 Watt inverter rated at 94% efficiency may only be 70% efficient in reality at a 600 Watt draw, while a 3000 Watt inverter rated at 92% efficiency may actually be 92% efficient at a 600 Watt draw.  So, that is an instance where bigger is better, because the new bigger inverters really have very little addition "background draw" over the smaller inverters, particularly the older ones.

However, that being said - Yes, you are correct in that you are generally better off having a smallest inverter that is comfortably rated for your load.  There are diminishing returns in energy savings, especially for each $ spent - which is why a lot of people use a separate inverter for small items and big inverter for kitchen appliances. 

But also worth recognizing that the using a higher % of an inverters capacity means it will wear out faster (in general, although brand is probably more important).

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Reply #17 –
My reason for getting separate smaller inverters is that from what I have read my Xantrex sw3012 is using 5 dc amps when it is at idle not inverting anything. The efficiency does not factor this in. I want to turn off the big inverter at night when only the refrigerator is necessary. Then turning it on in the morning for microwave and coffee maker use.
 Yesterday only generated 4.5 kwh, don't know why less than Sun. Is it possible that DW not using as much power as she went outside for a time and sat in the shade caused less current to be generated?

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Reply #18 –
Half that or less on my sw2812. I do not think your hybrid is any different.  See the info at magnum energy's web site and look at your specific units specs.

You will never be a zero load.  Too many appliance lights on.

The other modes were less power consuming than the 30 watt zero load.

You can call Magnum.  They are USA.  And speak English.  Michigan?

The me-arc controller has adjustable everything internally.

Read up?

As was stated a smaller inverter may have less efficiency.

not 5 amp as far as I know.

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Reply #19 –
Bob remember mine is a Xantrex different than yours not hybrid.