Documenting my solar install

[SternWake]

Let me clarify a bit. You've got to take the original battery stud clamp terminal(-) negative/ground cable off of the engine battery. This removed cable needs to run to the load side of the shunt. Either you mate this cable end to the load side of the shunt, or you leave it disconnected and wrap it with electrical tape. Then you run a new Ground cable from engine block to the load side of the shunt. If there are multiple black (-) wires attached to original battery clamp (-) it is probably better mate new cable to the one removed from the engine battery.

A new cable needs to go from the battery side of the shunt, to the engine battery (-).

If you do not do this, then your battery monitor will only read a fraction of current the alternators are making for the house batteries to gobble up.

Thick copper, properly terminated, is a requirement for best performance. Go no thinner than 2 awg or you will notice the starter spinning slower than before.


Since you already made a boo boo in marking one wire, double check that a frame ground and PV(-) do not meet anywhere before the PV(-) input on the charge controller.

And once again, no ground wire/cable, can go directly to either house or engine starting battery (-) terminal, that does not come directly from the battery side of the Shunt. Even a 10 gauge ground wire bypassing the shunt can throw off the amp reading by 20 or more amps, making your Trimetric as accurate as a 225$ paperweight.

 

[Seraphim]

That doesn't really seem feasible, running a new cable from the engine battery to the shunt since the camper is designed to be removed from the truck, in which case those cables from the truck to the camper would have to be removed somehow. The only time the umbilical cord between the truck and camper is attached is when I'm driving the truck. Other than that, there is no connection between the truck battery and the camper. The umbilical cord has all the proper connections.

No other wires come directly off the house batteries. Nothing bypasses the shunt. Even when the umbilical cord is attached, anything to and from the house battery goes through the shunt.

Except, again the solar which goes directly to the battery. I monitor power to the battery from the panels via the controller.

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Only the solar power does not go across the shunt, I meant to say

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The camper does not use a frame ground...

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Quick diagram

 

[SternWake]

I concur, but you are not going to be able to count alternator current into the batteries.

Now if the solar is able to hold ABSV for 2+ hours, then the loads from the 'full' batteries will be counted.

It is just when you drive in the morning with low batteries, the monitor is not going to see a majority of the alternator current, and will read as if the batteries are more depleted than they are.

I am not sure the triggers which return the trimetric to 0 AH from full and 100% state of charge, but you might be having to reset or rezero it more often and not just trust the reading, especially when alternator contribution from your two alternators, is significant, and if your alternator charge cable is thick, it will be significant, but the 'umbilical' might be the weak link that severely limits alternator current anyway.

I Know truck campers have resolved these charge limiting issues by adding a thickly cabled hi amp connector in addition to the umbilical.

Why do you not have the trimetric reading solar panel power? I realize your charge controller itself displays this, but how do you expect the trimetric to read the solar current into the batteries if it is not run through the trimetric's shunt? The trimetric and solar controller are not communicating telepathically and doing some math One is a separate system monitoring current from one source in one direction, and trimetric is also supposed to do this task, as well as count all current into and out of the batteries.

If it is not seeing all the current flow, in both directions whether charging and discharging, it is simply a useless tool and you can almost never expect the trimetric to have any accuracy, what so ever. it will just be a overpriced voltmeter that displays a bunch of other useless information due to its inaccuracy.

The camper is grounded to the truck chassis when connected via the umbilical. How else would alternator current be able to reach house batteries inside camper?





You might not need the extra juice though.

 

[Seraphim]

Yes, the campers circuits are grounded to the truck chassis when connected. But they have no frame ground without the umbilical.

I didn't hook the panels wire to the load side of the shunt because I was merely following directions during the install. I only use the basic functions of the battery monitor, checking voltage and amp flow across the shunt, and percentage of battery remaining. I'm not using the monitor to its full capacity, but I'm not interested in doing so. I just like knowing what the draw is at any given moment, and about what percentage of the battery's capacity I'm using on site. The monitor seems to know when the battery Has been charged by the panel's - the remaining charge on the trimetric increases as the panels recharge the battery. Mostly, I just want to know when the battery is discharged halfway so I can measures to recharge by other means, of necessary

I get the feeling I'm still missing something, though. If the battery's being charged by an alternator, the trimetric should pick up on that. Yet you're telling me current from the alternators will confuse the monitor, and I'll have to zero the monitor. Haven't wrapped my head around that. If you think it will make the trimetric readings more accurate, whether I understand it or not, I'll connect the panel lead to the load side of the shunt so the trimetric reads the panel's input.

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You're also saying the trimetric will not count current from the alternator, yet it appears to do so when Imidle the engine: it gives about an 8 amp reading.

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Sorry if I'm appearing dense, here

 

[SternWake]

How many wires are in the umbilical?

Dont worry about sounding dense, I remember when this was new to me and found it confusing. I'm trying to make it so all the pieces come together for you.

Lets leave the current counter inside the solar charge controller out of the equation for now.

The trimetric needs to know the total amp flow both into and out of the batteries to have any chance of being accurate what so ever. You can't just pick and choose what you want to have it monitor and have any accuracy what so ever. It will be misleading in the extreme and the only accurate figure on it will be the voltmeter and how much load is on the battery. You could've gotten a 18 dollar combo voltmeter and Ammeter from Amazon or Ebay for this purpose

Yes the solar Controller (-) has to goto the load side of the shunt. It cannot go to battery (-) without first going through the shunt. Think of the shunt as a remotely mounted battery (-) Stud to which you attach every Negative wire, whether it be a charging source, or a load.

If the Umbilical cord has only one black wire, one ground path, which it should, then this wire needs to go to the load side of the shunt.

If you do not have these current sources flowing through the Shunt, your battery monitor does not have the information it needs and ALL its figures regarding battery % or Amp hours from full, are completely and overwhelmingly worthless, and worse, misleading if you place any stock in their importance.

So, by not accounting for these charging sources, you are not just not using the trimetric to its full potential, you are not using it at all.

Yes it will report loads on the battery, but it is not counting down from an accurate figure.

If you leave it as is, when you start camping, the monitor is going to at some point say 320 amp hours from full and negative 150% remaining, simply because you are not having the charging sources flowing through the shunt.

You can place the umbilical's negative cable to run through the shunt, you can easily move the controller's (-) through the shunt, and blammo, it is counting All amps into the batteries, and all amps out of the batteries, and can do the math and say," You are now 25 amps hours from full,"
and be ~90% accurate.

As you have it now, you have 0% accuracy as to amp hours from full and State of charge %. Zero. Somehow it is seeing charging voltages for extended periods and deciding to start from 100%, but it is not counting amp hours into and out of the batteries, and once you put it into use, wired as is, it would make very little sense, these numbers it displays.


Please forgive my blunder about moving the battery cable, I was thinking in terms of a single chassis like a Van or a permanently attached truck camper, not two separate systems mated by an umbilical cord whose single ground, can be passed through the shunt for properly measuring alternator current.


As for the amp hour counter on the solar controller, that is an additional data point, Say if your trimetric says in a day your returned 68 amps hours into the batteries, and the solar is saying you returned 48, then you know the alternator contributed the other 20.


But.
When there are loads on the battery while the solar is going, the portion used to run the loads will be counted by the Solar's amp counter, but they will not be counted by the trimetric, as the trimetric is counting amp flow into and out of the batteries. When the solar is producing more current than needed to run loads, the current does not pass through shunt, but across the connectors attached to the load side of the shunt and is not measured by the Trimetric's shunt.

So 68 amps hours returned to batteries, Solar is saying it made 48, but 15 of those went to power loads while the sun was up, so the Alternator that day contributed 35 amp hours.

It really is an enlightening tool, but it has to be wired properly to be enlightening, and as you have it now, you are in a dark cave with a lighter that only stays lit for 3/4 a second at a time and can only be restruck every 10 seconds.

The good news is you only have to relocate 2 wires to get full functionality from the trimetric. The bad news is the Umbilical might fight you on this somewhat. Put the truck side of the cut umbilical(-) cable on the battery side of the shunt, put the camper side of the Cut umbilical cord (-) on the load side of the shunt,
And alternator current into house batteries will be measured.


With all loads turned off in daylight hours, including engine, the Trimetric's and Solar controller's + amp reading should be the same, or very close to each other.


Once you do this you will have an Ah Haa moment when You start turning things on and off and looking at your measuring tools that are now displaying the correct information. Then you dance the Jig.

And then perhaps obsess about thickening those umbilical (+) and (-) cables to increase alternator current, so the alternator can partially power your wife's 2000 watt hair dryer.

Or not.

 

[SternWake]

I messed up above on the paragraph beginning with 'the good news" Dang the 5 minute edit limitation

Put the (-) side of the umbilical cord from the truck to the same side of the shunt as the PV(-) negative, and all load's (-) to this same side of the shunt.

Only 1 cable need goto house battery (-). Only this single cable goes to the other side, the battery only of the Shunt. So source/load side of the shunt will have at least 3 cables on it. PV(-), Umbilical cord (-) and All loads (-). I use a Negative buss bar for all my (-) loads rather than wire each load to the shunt itself

That is all you need to do to read alternator current and Solar current into battery, and this will allow you to use the trimetric to full advantage

The (-) umbilical is a source/Load.

Nothing but this single wire from battery side of shunt, goes to battery (-)

 

[Seraphim]

Ok. Makes sense. Your patience is appreciated.

Nice part is, I probably won't have to cut the umbilical. It attaches and removes from outside of the camper. On the inside, the cables run separately. I'll have to remove some cabinet parts to check, but it's entirely possible the ground from the truck already runs to the shunt directly, rather than going back through the electrical control center (not the proper name, I know lol) first. Although, I don't understand how that would make a difference, if it did.

I assumed the trimetric was reading the current capacity directly from the battery, but from your explanation, it seems it tracks current charge level mathematically, based on its knowledge of what the battery is SUPPOSED to have, minus (or plus) what has travelled across the shunt.

I'll let you know what I find after checking the existing wiring. I'll go ahead and move the - panel lead to the load side of the shunt, while I'm at it. I'm calling Renogy when they open about the controller. I suspect it needs repair/replacing. It may have been something I caused, although the manual states confusing the wiring will not harm the controller. We'll see.

Thanks again.

 

[Seraphim]

Moved the negative panel lead to the shunt



The two black leads in the photo, one from the shunt and one from the positive battery terminal, run to the charge controller. The red cables from the positive terminal connect to the second battery (in parallel), a small fused wire which powers the trimetric, and the wire that runs to the load.

its impossible for me to accurately trace the wiring without disassembling the cabinetry - sink included - which I am loathe to do. From what I can see, from where the umbilical attaches, there are a group of smaller wires - probably the lighting harness for brakes,mounting lights, etc, - two heavier guage wires (8?) which run back towards the electrical panel, and run back to the front, but do not connect to the battery. There is a (10?) guage wire that drops down into a nest of connections, and from this nest is the negative lead to the shunt and battery. I can't physically reach the nest of connections, so I can't be sure exactly how the wiring is run.

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After moving the lead to the shunt, I noticed an increase in phantom draw registering on the trimetric - from .2 to .3. I assume this extra draw comes from the charge controller.

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Reference the wires: the wire I mentioned above which drops down is white and is the same guage as that which runs to the shunt. There is also a black wire of the same guage - I assume the positive.

 

[SternWake]

I am a bit confused since you have both red and black wires going to the same battery terminal.

YOu should really use some black tape and label those wires, especially before replacing those batteries, whenever that becomes a requirement. There are lots of reports on other sites by those that replaced their batteries and screw things up by crossing wires on reinstallation.

I can't really help figure out things from here. The thickest (-)wire which comes from the umbilical needs to goto the load side of the shunt and not directly to either house battery (-)

There should be at least 3 wires on the load side of the shunt, The (-) from the umbilical, the PV(-), and likely the TC original wire which attached originally to a house battery (-).



the increase of parasitic draw at 0.1a being registered after moving the PV(-) to shunt is a bit extreme, Imo, but I am not familiar with Renology's products. Is the display backlit? My battery monitor increases by 0.1 amps when the screen is lit up and decreases by 0.1a after a minute without touching a button, when it goes dark.

As you stated, the trimetric has no ability to probe the battery and determine state of charge. It counts current into and out of the batteries Via the Shunt, and if there are loads, or charging sources on the battery that do not go through the shunt, then the trimetric is blind to those charging/discharging currents. The fact that it was displaying a 98% must be from being held at higher charging voltages for x amount of time by the solar, which was not being registered before you moved the pv(-) wire to the load side of the shunt. Or perhaps it just starts at 100% charged when initially powered up. Anyway unless all loads and charging sources flow through the shunt, it has no chance of any accuracy in terms of battery % or AH from full.


I notice that battery cable paralleling the (+) of the batteries is an Auto parts store cable, with steel ring terminals. This wire will cause issues at some point and cause more and more resistance. The steel is not a great conductor, and will corrode quickly in the presence of charging fumes. You can mitigate this somewhat by filing the steel super shiny, re attaching, and covering the terminal with grease.

A quick anecdote. I had one of these store bought steel ring terminaled 4 awg wires, in parallel, with another 4 awg wire, which had pure copper ring terminals, Between my shunt and house battery.

With my Clamp on meter over both wires it registered a 4.2 amp load. Same as battery monitor.
With my clamp on meter over just the steel terminaled wire it registered 0.6 amps
With my clamp on meter over the copper terminaled wire, it registered 3.6 amps.

After I cut off the steel ring terminals and replace with copper, both wires shared the load equally The steel ring terminaled wire had so much more resistance, 85% of the current chose to flow over the other wire.

Does your truck camper have an AC powered charging source too, like a converter, Wfco, Progressive dynamics/magnatec/parallex are the popular preinstalled converters? If so, the (-) cable of this charging source needs to goto the load side of the shunt too.

Since I am not familiar with your truck camper, I really have no idea how they ran the wiring originally. If you disconnect the batteries in the TC, and plug in the umbilical, I imagine all the exterior Signal lights still function, but none of the interior TC electrical devices should operate. Perhaps the TC subforum on Rv.net has somebody more familiar with your stock electrics who can help if needed.

Do note that if the batteries are nearly fully charged, they cannot accept much amperage from either the solar or Alternator or any charging source. But, when discharged they should be able to accept very large currents. Your dual alternators should be able to feed those two well depleted batteries initially, well in excess of 100 amps, but the 8awg cabling will never pass that much.

This might not make much difference in your outings, or it might. Just know vast improvements can be made in alternator charging by installing thicker copper to the house batteries from the alternators.

Explore this if the solar does not supply enough for your needs, as the alternators can take the batteries from 50 to 80% rather quickly when thick copper mates the two devices. Thin copper here is like a sprinter or marathon runner being forced to breathe through a kinked cocktail straw.

I would recommend getting some red and black tape and making ground wires Black and positives red, and also labelling each wire. Blue masking tape written on, and covered with clear scotch tape works well, though there are other ways to label wires to minimize future confusion. While you might be familiar with the wires now, In a year you will look at them and be like "WTF" where the hell does this wire come from?

Also if you have someone else work on your electrical system these labels will be greatly appreciated and minimize their labor.

Is there a method to vent charging fumes?

If you take the trimetrics twisted pair sense wires off one end of the shunt, and put both sense wires under the same bolt on the shunt, the trimetric should read 0.00amps. My IPN pro remote requires this be done and then the monitor re zeroed, so that it can accurately measure currents, and I turn off the backlight function during this rezeroing as it does draw 0.1 amp.

 

[Seraphim]

Yes, I plan to label those wires, but since they're only 18" from the comtroller it's easy to check visually.

Yes, there was a backlit display on when I checked the draw.

If I disconnect the batteries and run on shore power, everything works.

Everything except the shunt, the battery monitor, and panels are original wiring. I suspect, from the wiring nest, that the negative lines from the umbilical and from the loads are connected prior to running to the battery (now the shunt). But I can't comfirm that in the nest of wires. The system works, but there has never been more than one cable running to the negative terminal. But, as I said, it works. I assume the designers knew their stuff, but then again...lol

This is the best photo I could get: the bunch of wires from the top - where the hole is cut and partially covered by a wood strip - are the wires coming from the umbilical cord which also attaches to the rear of the truck.

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The camper's electrical panel converts AC to DC, has circuit breakers, DC fuses, and all the loads come from that panel. In the last photo, there is a double wire (encased in plastic shroud) that runs for the umbilical connection back towards electrical panel, then seems to return and crosses over towards the propane furnace and 2 way fridge.

I think I'll just leave it be lol.

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I have always asumed there was a charge controller in the electrical console, which controlled the charge to battery - hence, only one negative wire, since the alternator and shore power would be routed through that controller. But I have no immediate knowledge of such.

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One negative wire to battery

 

[SternWake]

Well now that you got the polar PV(-) running through the shunt the trimetric should be monitoring all current into and out of of house batteries. As long as nothing goes directly from a Load or source to either house battery(-).

You will need to deplete the house batteries to see both what the solar is capable of producing, how much the alternator can feed through the cabling, and what your AC to DC converter can also supply when plugged into the grid.

Unplugged from truck and grid, t with no loads present, the solar controller display and trimetric should agree on amp flow within 0.1 or 0.2a at the most. If they do, then have more confidence in your system.

My only concern is that ALL the alternator current into house bank might not be measured when truck ground and TC ground become one through the umbilical, and that the alternator charging circuit is a kinked cocktail straw not supplying what it could with thicker copper. But this might not be a factor in your use. if you find the solar cannot keep up when you are on an outing, then explore thicker copper to house battery

Also, some solar current might still be going to engine battery when mated. depending on the isolation method

Put a DMM on the engine battery (engine not running) when solar has the house batteries over 14. You do not want to see 14+ at engine battery as that means when umbilical is hooked all batteries are in parallel and house loads can draw down engine battery.

Have fun with your new tools and current source.

 

[Seraphim]

Thanks Sternwake - I think I have a pretty idea, thanks to your patient tutelage.

Since the trimetric had me close to a full charge, I put the unit on shore power and I'll check the specific Gravity. Once I get the controller swapped out, I'll run the batteries down - 50% or further? Then I'll follow your advice.

I already know there is no isolator installed - f I take it off shore power, disconnect the house, and keep the engine off, the 12v electronics on the camper still work if the umbilical is connected. The engine batteries can be the only source.

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Pretty GOOD idea lol. None of my ideas are ever pretty...

 

[Seraphim]

Just received an email response from Renogy tech - they confirmed the controller will need replaced, and will have someone from customer service contact me.

 

[Seraphim]

I unplugged the batteries from shore power this morning, and waited several hours to take a hydrometer reading.

The first batteries readings gave 1340, and stated to remove 8 points for temperature. 1332
The second batteries readings gave 1300: minus 8 for temperature is 1292.

1260 is 100% charged. The trimetric showed the batteries at 102%

There was room to add water to the cells, but the plates were well covered.

I assume the batteries are still n good condition. They've never been below 50%. I don't recall them ever being below 60%. I suppose I can add water, wait a while, then check the readings again. Might be more accurate, because those readings seem high.

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Any thoughts from anyone?

 

[SternWake]

One mush be leery of Bubbles sticking to the hydrometer float and giving false high readings. 1.332 is way too high a reading, this level of sulfuric acid will eat the lead plates quickly. Usually the first cell dipped will have the most bubbles sticking to the float, and getting them off is not so easy.

One should try and do a couple bulb squeezes to mix up the electrolyte too, pulling from one side of the cell and discharging it to the other side, as if the battery was not recently charged, and one just sucks up the top layer, then the reading will be low, and of one bottoms out the rubber tip on a cell, so that is sucks electrolyte from between two plates, it will pull the denser acid from the bottom of the cell.

Where did the 1.260 figure come from? Exide?

Batteries usually vary from 1.275 to 1.300 when fully charged. Batteries made for hotter climates will usually have the 1.275 while batteries for cold climates will be nearer to 1.300, but this is not written in stone.

USbattery says 100% on mine is 1.280 but I've gotten them to 1.295 temp compensated. so take max SG figures with a grain of salt or 2.

After filling the battery to just below the hanging arms, the SG readings will tank to the 1.220 level. Physical agitation is needed to mix the distilled h20 into the electrolyte.
Charging at 14.4+ volts will bubble the electrolyte, mixing it.

After filling the max SG goes down a bit, and voltage under load also goes down, so refilling the battery might give one a good feeling, but those watching their voltmeters closely might be alarmed to see the battery not 'performing' as well as it did before refilling. This depresses me every time I refill, even when I expect it.

While days on shore power, and plugged in will usually allow the SG to max out, sometimes, especially on regularly and deeply cycled batteries, the SG will not max out until after an EQ charge is performed.

When batteries are brand spanking new, one should top charge them, not the electrolyte level, and take bubble free Hydrometer readings, and use this as a baseline SG.

Older batteries should be equalized, and then have the maximum SG of each cell noted, but days and days on shore power might max out the SG too, especially of the solar is doing an Absorption voltage cycle every day for an hour or 2. Batteries have different personalities that one can notice when getting intimate with the hydrometer, So direct comparison is not very effective. For accurate readings one must compare readings to previous readings taken with the same Hydrometer on the same battery and the same cell. Usually lower cells will always read low, higher cells will always read higher, and to save time in the future, one can just dip the lower cells and know if the battery needs more charging or not.

Don't forget to rinse the Hydrometer out after each use.

You can add distilled or deionized water to just below the hanging arms in the cell. Usually once a used battery has some portion of the plates exposed, the battery dies shortly after refilling, so it is important to never let it get that low. The batteries will start to use more water as they age, and when cycled every day, and sitting at absorption voltages for 2 hours each day, they will use more water too.

Dont forget to wear eye protection if checking SG, especially if the batteries are charging at the time. Wear clothes you don't care about either, as no matter how careful one seems to be, one finds holes in their clothes the next day.

I used 56 Amp hours last night from my single group 31 battery according to my monitor. We are getting stormy weather. I am only seeing 1.3 amps of charging current as I type. There is no chance for the solar return to full charge today, but I am glad that when I do go for a drive, my alternator will be able to send 60 to 80 amps into it at 1950 engine rpm.

If I press the button on my 150 amp circuit breaker that feeds the batteries directly from doubled 4 awg cable, the amperage drops to about a third.

This is why I go on so much about maximizing the capability of the alternator via thick cabling, to feed hungry batteries. My solar stands no chance today, and without driving to restore the battery to 85% or so, it would be down to 20% by morning tomorrow, and this is rough on a battery, and it is supposed to be cloudy again all day tomorrow too, and I'd be screwed without the alternator.

 

[Seraphim]

Thanks again, Sternwake.

The 1260 came from the hydrometer package - I should have the Exide numbers in a file on the iPad.

I assumed the density readings were high. As I said, the plates were all covered, but there was still room for water to be added to the proper level.

Renogy customer service emailed me, and they're sending a mailing label. As soon as they see package in transit, they'll call me to get information to pay for the upgrade to a 40 amp MPPT controller, and ship the unit.

While I'm at it, I might as well rewire the batteries and cables to to the controller with thicker wire, since I'm upgrading the controller. Mighty as well eke everything out of the system that I can, especially since it might be March before we get any direct sunlight around here. At least I know, even in light rain, the panels will keep the batteries up when the unit isn't being used.

My feet are itching to get back on the road, but some obligations have come up. I could shrug them off, but it would disappoint people I care about, so may not launch out of here until late January.

But I'm getting cabin fever.

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Oh and Sternwake - if you saw my work clothes, a few holes might be an improvement lol. But I appreciate the safety warning.

 

[SternWake]

I hear you on the work clothes. I've got some white shirts that are stained and holed everywhere, yet smell like fresh laundry detergent.

1.260 is usually where hydrometers display the green. Exides specs will be interesting, but i doubt they will be truly representative of each and every battery.

Just look for bubbles sticking on the float the next time. Small bubbles, barely visible, can make a 0.005 difference. A large bubble 0.015. Rarely does flicking the HM knock off the bubbles. Usually a couple more bulb squeezes, and a return filled with some air knocks the bubbles off. If it is one of those plastic hydrometers. I can rarely to get that float free of bubbles, and I consider it a waste of money and a nearly worthless tool. I actually use it to suck water from a distilled h20 bottle and fill the cells.

I drove 14 miles today, the alternator returned 30 AH of the 54 I was down before starting engine. It was having difficultly getting above 14.2 on the depleted battery. I think it got too hot to go higher when making 50 to 70 amps, as it will max out at 14.9v usually but near the end it was touching 14.4v at higher rpm. 1.3 amps was the peak I saw from solar today. most of the day, thick clouds. 0.6 to 0.2 amps from 200 watts.


So I'm gonna conserve a little bit tonight as I didn't get much above 80% and right now I am down at 39 from full, 12.1v under a 4 amp load.

BUt I have a fully charged AGM battery ready to start the engine, and this battery can be depleted well below 50% and still easily start my engine, and I can switch all loads to this battery at the flip of a switch.


I'd be interested what your trimetric says when your batteries are depleted and you start the truck. Do you have a helper to watch the monitor, or start the truck, so you can watch the Ammeter during cranking and right after?

Good to hear Renology is not fighting you on the return and upgrade.

 

[Seraphim]

Renogy has an excellent customer service reputation.

I've never watched the trimetric during starting. I try to keep the truck batteries and house batteries separate, by keeping the umbilical disconnected until I'm ready to drive, and need the brake lights. I don't let the house draw off the truck batteries, ever.

I've watched the amp flow at idle, and the amp flow wasn't that high on the trimetric. Next time I'll have DW bring the RPMs up to speed and check the flow. But I know the alternators have replaced an estimated 84 amps in about three or four hours, so it must be doing more than the 8 I observed at idle.

Generally, we have the .2 phantom draw, and we run the fridge on propane which increases the draw to .8. We run the water heater for about 10 minutes at night. We might have an LED light on for an hour. That's pretty much our usage on a daily basis. Charge our electronics phones, iPads) in the car, or we have a jump battery.

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We get 4 nights at least out of 105 AH (50% of 210), but even out 4 nights I don't recall seeing the battery level below 60%, ever.

So if use about 25 amps a day, assume we'll have to use 40 amps to recharge (that's budgeting high, I know), our panels should still really extend our time on site before needing to recharge.

 

[SternWake]

I did not use much electricity either when my solar system was new. Now i try to use up enough that my panels have work to do the next day.

When you know that half of a Sunny day could recharge a fully dead battery enough to start the engine, then one does not worry as much about how much battery power is used.

I'm making my batteries work, well my flooded battery anyway. My AGM gets pretty light duty for the most part btu I have taken it down low a few times. The AGM simply loves Super high recharge rates, so I like to depleted it a ways, then feed it 41 amps from my MEanwell, or 40+ amps from my alternator.

It does take higher amps for longer and recharges to 95%, faster than my Flooded, but that last 5% is still a female dog which takes a long time, in comparison to 50 to 95%. About 2x as long.

It sounds as if you'll not need much input from those 2 alternators, but if you find you do later on, lemme know, and we'll get some fatter copper between your alternators and house batteries in the TC

 

[Seraphim]

Thanks Sternwake.

We've been driving a lot in our travels, and the alternators pretty much took care of our needs. But for financial reasons, and enjoyment reasons, we plan to do fewer miles per month, and spend more time exploring a single area. The solar panels may be overkill, but I like the thought we can lolly gag around one area longer, if we wished. And I hate the thought of burning fuel just to recharge the house batteries.

I had actually considered dedicating one alternator for recharging house batteries, but it's never seemed necessary. Our truck is a basic work model - we're not big on on 'extras' in a vehicle - but I like the fact this one was prepped for a snowplow: had some beefed up front end components and that second alternator.

Well the charge controller swap should be a cinch - probably take a week to get the new one in. In that time I can pretty up the rst of the install: Dicor down the wires on the roof, put the fuse for the panel's on the proper wire (unless a fuse will work on the negative wire), and I'll have to splice the negative wire from the the panels back together. Maybe I'll go ahead and splice both panel wires a little longer, and see if I can't tuck those connectors upstairs under the panel. So much for a good free install...

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I'll also add a photo of the lap seal on the mounts, so people considering an install themselves will see how it looks.

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Lastly, I'm considering adding a power point station so we can recharge the phones and iPads from the house batteries, if needed. Not sure of the power consumption for recharging those devices...

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'Good free install' above was supposed to be 'goof free install'

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I do know to make good tight splices, and solder them for strength and protection.