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Old 10-04-2018, 06:49 PM   #121
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Originally Posted by Wolfwhistle View Post
AM,

Will try to answer your questions. My background is 46 years in telecom / datacom - installer to Application Engineer. My mantra was "I might not be able to fix it, but I can make it so no one else can."

Charger to battery voltage drop should never be more than a 3% across the conductor (one way). My 300w array is capable of 17.1 amps at Vmp of 17.7 volts. I have seen 18 amps initially which drops rather quickly / naturally as voltage rises to Absorb. Less than perfect sun I've seen 15 amps as current drops and voltage rises over a few hours. "Full" is displayed when 2% of Ah is reached at the same time voltage is at the absorb set point.

Inverter to battery should be no more than 1% voltage drop and that at the peak it can produce. My old 2000W Magnum peak was 3200W and the main breaker was 250 amp. Catastrophic fused at 300A. Cabling all #4/0 to the inverter. Even with 460 Ah bank, it wouldn't take long to deplete the batteries. Of course, drawing much higher than C20 gives you far less than the rated Ah, the ole Peukert effect will get you every time.

To me its about voltage and less about amps. So if in less than ideal light condition the current will certainly be lower than ideal, but if voltage levels are also lower than ideal you simply will have a less than full battery and it takes longer. If this is a common occurrence that would be telling you to add more panels if possible. Making 14.6v from 17v from the panel is easy but if low light only nets 14.6v you would end up with 14.2v with a 3% drop or 14.3% at 2% or even much less. An analogy is trying to fill a tire to 80 psi with a 81 psi source. Voltage is the pressure and the volume in the tire is the amps. Its about voltage. But a battery that is charged too slowly never reaches true 100% either.

Here's what's so cool. The SC2030 can placed anywhere along the route from panels to battery without a problem.

For me it is about having a full battery at the start of the evening, than it is worrying about long life. But, fulling charging every time, plays hand in hand with long life.

I haven't decided on the inverter size yet. I will not be running a microwave, so 1500W or even 1000W will probably be enough. You are right about matching to the bank. 230Ah and 1000W is a good match for short duration use. If in this small trailer if a microwave was a necessity, I think to get the Ah I would need considering the logistics (weight primarily) I might enter the LiFePo4 arena, kicking and screaming all the way. But guess what the Trimetric pair is ready for them. So, no microwave, but I might find myself accommodating the DWs curling iron / hair dryer. I like to overbuild in case I might need a 2000W at some point. It is possible to under fuse the circuit to limit the DC load. Such as installing a 2000W inverter but using a 175A breaker.

So, why I like the SC2030 is its size, simplicity and cost. I have had 4 packages / systems with not a single issues. Bogart support is very responsive when I have needed them. SC2030 is $119 and the TM2030 is $160. A required shunt is about $24

Their charger is rated for 30 amps; it can reduce current to 31 amps when higher amps are being delivered without harm. Its silent. It can work autonomously, but with the TM2030 is when you get the most out of it. You can also have the TM-2030 by itself.

The TM2030 RV model is the smaller faced one that I like.

The docs that Bogart provides are a lesson plan unto itself. Someone wanting to get into this, could get a TM2030 and with the documents pretty much learn all they need to do it. You can start out with generic settings and go deeper into it as you want to. History functions are very nice IMO

IMO this setup is good for these small systems with 36 cell panels in parallel. I can see the advantage of MPPT in grid tie (required) or in larger systems. When using higher voltage panels or several in series with small gauge cabling or when you have long wire runs ... makes sense.

What I don't buy into is all the hype and companies selling something with an agenda. Great marketing and not so great products and industries in bed with other industries that are out for a profit without your interest in mind. Getting the latest thing can be more bleeding edge than cutting edge.

Clint
Thanks WW for the reply. I'm not sure why I didn't see it until now. I had a feeling that you had some "experience" and we could learn from your expertise.

I like your tire pressure analogy. I like your statement to limit drawdown to C20 and Peukert effect. I believe even a 1000W is more than I want to draw from my batteries as they drop to 12V immediately when turning on something like a hairdryer. Do you have any suggestion on that effect. Is it ok to run the 1000W inverter which causes the battery to immediately drop to 12V or even 11.8V for a few minutes? Will it damage the battery? The battery will bounce back to 12.6V or so quickly upon turning off the load. How about a smaller draw, like the furnace (7A)? What is the lowest battery voltage you would suggest with wet cell golf cart batteries? I feel you could go as low as 11.8V under that type of load (7A) because the battery would quickly bounce back to 12.1V when turning off the load. Your thoughts?

I am really sold on running panels in a series-parallel configuration with 400W on the factory pre-wire and an MPPT controller. Your voltage explanation matches my thinking, especially since the Victron 100/30 controller needs battery voltage +5V from the panels before it will turn on. With a series-parallel configuration, the voltage is doubled so there is always battery+5V when there is light. The Victron will turn off when panel voltage drops below battery+1V. The Victron manual actually recommends a series-parallel configuration, probably for this very reason. The Victron also turns to float when the battery voltage remains constant for a period of time in absorption (not sure of the exact numbers but my system floats nearly every day). Yes, my goal too is to have fully recharged batteries every day - highly likely 400W of solar and reasonable usage/sunlight.

Thanks again for your reply!
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Old 10-05-2018, 06:19 AM   #122
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Originally Posted by AirMiles View Post
Thanks WW for the reply. I'm not sure why I didn't see it until now. I had a feeling that you had some "experience" and we could learn from your expertise.

I like your tire pressure analogy. I like your statement to limit drawdown to C20 and Peukert effect. I believe even a 1000W is more than I want to draw from my batteries as they drop to 12V immediately when turning on something like a hairdryer. Do you have any suggestion on that effect. Is it ok to run the 1000W inverter which causes the battery to immediately drop to 12V or even 11.8V for a few minutes? Will it damage the battery? The battery will bounce back to 12.6V or so quickly upon turning off the load. How about a smaller draw, like the furnace (7A)? What is the lowest battery voltage you would suggest with wet cell golf cart batteries? I feel you could go as low as 11.8V under that type of load (7A) because the battery would quickly bounce back to 12.1V when turning off the load. Your thoughts?

I am really sold on running panels in a series-parallel configuration with 400W on the factory pre-wire and an MPPT controller. Your voltage explanation matches my thinking, especially since the Victron 100/30 controller needs battery voltage +5V from the panels before it will turn on. With a series-parallel configuration, the voltage is doubled so there is always battery+5V when there is light. The Victron will turn off when panel voltage drops below battery+1V. The Victron manual actually recommends a series-parallel configuration, probably for this very reason. The Victron also turns to float when the battery voltage remains constant for a period of time in absorption (not sure of the exact numbers but my system floats nearly every day). Yes, my goal too is to have fully recharged batteries every day - highly likely 400W of solar and reasonable usage/sunlight.

Thanks again for your reply!
We need to consider that a battery is a chemical tank and doesn’t store electricity. What you are seeing as low battery voltage under load is why you can’t go by battery voltages alone to determine “state of charge” or SOC. Voltage is temporarily low (load) or high (charging) naturally / normally. The larger the bank the less the effect. I would think that a 12 volt battery (12.65 or 12.7 Vdc full), under maximum load, should not drop below 10.5 or 11 volts, something like.

Have you ever read battery voltage as you start an engine in a car or truck? It might surprise some, but no harm is done. It’s temporary. You could say that it recovers. It would bounce back to near full. A 1000W inverter could pull 84 Amps at 12 volts, or even more depending on its peak rating and how you fuse it, etc. However, most inverters are used below or even far below their capacity. And running a hair dryer for 10 minutes is not an issue.
That 84 amps would, without calculating Peukert effect, probably reduce a 230 Ah bank to below 50% SOC in about an HOUR (84 Ah); maybe even lower. If you were to run at 1000W for extended times, the bank would have to be increased in size or change your “wanter”. But, a short duration load of 125 amps on the battery would do no harm.

I was tempted to go Victron MPPT and use series-parallel since it is possible to use the factory 10 gauge prewire. This is huge IMO. Running 6 AWG was a royal pain. Why I didn’t might be unique to my trailer, because unless I move or eliminate the OTA antenna, I only have decent space for three panels; and of course, series-parallel requires an even number. I went with the Eclipse model (Renogy) because of their dimensions. And, I didn’t like the look of panels hanging off the side of the trailer when placed beside the air conditioner, not to mention the inevitable shadow. If I did, 6 panels would be possible. This trailer is narrower than some.

I might go to the fourth panel, but not sure I need it. I have always preferred parallel because of the effect of shadows. So this depends on where you go and under what conditions. Series (higher voltage) would result in better performance in low light. Even my old-school Trimetric turns on with a full moon. I think I’ve see the charge light on under street lights. I would think Victron recommends series-parallel to advantage its ability for higher voltage in both smaller wire gauge (voltage drop) and low light performance.

In full sun, the actual results of charging PWM vs. MPPT might surprise a few folks, and if you have room, etc… adding an additional panel with the money saved could make PWM even better than MPPT. I would definitely go MPPT if and when I think it could be an advantage such as using in-place factory wiring! Having control or information on a smartphone is pretty cool in and of itself.
WW
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Old 10-05-2018, 08:00 AM   #123
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Hi

Indeed a lot depends on your exact batteries. However, with lead acid there is only just so much you can do. Running an inverter at 1KW may well get you up into the 100A region. A lot depends on wiring and just how efficient it is at full load (also the battery it's self).

With stock batteries, that's a discharge rate of a bit over capacity / 2. Very roughly speaking that will drop your capacity by about half on typical RV batteries that have been out in the field for a while. So, doing the math, if you thought you would get an hour of running full load ( 100AH usable and one hour), instead you will get about 30 minutes or so usable capacity.

The big problem is just how you can tell when you have run out of capacity? At these rates, a voltage monitor is utterly useless. The voltage drops quickly due to internal resistance of the battery. You have to use some sort of current shunt based device if you want to have any idea of where you are.

Knowing where you actually are *is* pretty important. There are a lot of cases where people *think* the battery is fully charged (by reading voltages) and indeed it is only at about 70 or 80% charged. In that case your 30 minutes is getting closer to 15 minutes ....

To make this even more confusing, as the battery discharges the voltage drops (a lot). As that voltage drops, the current to supply 1KW goes up and up. Your discharge rate does not actually stay constant in terms of current. It's a constant power load. At some point your inverter will kick out due to under voltage. On a practical basis *that* is the point the whole thing stops working.

Bob
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Old 10-05-2018, 08:25 AM   #124
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Good stuff WW & Bob! I will add the wife's hairdryer on low settings as an approved appliance. My wife thanks you both! I'm ok with abusing my batteries and replacing them more frequently, but I just wasn't sure how abusive running a 750W hair dryer was to the batteries when I saw how low the voltage dropped under that load. I also appreciate the description of how the battery works as a chemical tank. I always thought it stored energy, but now it makes sense to me how it works and why a hydrometer is the best tool to test SOC.

I worked for in the electric and gas industry for years, but as a financial analyst. Its the analyst portion of my brain that needs to figure all of these electrical issues out. I also was an analyst in the plumbing and air conditioning business as a second career and then owned and operated a plumbing company for several years before retiring. So I have a broad knowledge that's an inch deep in many areas. Just enough to get me in trouble!

Thanks again for the education.
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Old 10-05-2018, 10:47 AM   #125
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Bob said: You have to use some sort of current shunt based device if you want to have any idea of where you are. Knowing where you actually are *is* pretty important.

Bob & others, I'd like to explore this issue a little deeper. I have not been a proponent of installing a Victron BMV-712 or similar monitoring device. I chose to not install one. I'm sure its "cool" to have one as it provides lots of data. Its not that it doesn't provide accurate information. Its probably more because I think its a pain to install the shunt and I don't know where I would mount the shunt or the monitor. Its not that expensive if I really wanted one, but I just don't believe it provides enough useful information to be worth the effort and cost to install it. I chose to install the Victron BatterySmart module instead, which provides voltage compensation in addition to the temperature compensation of the BMV-712. I was told that you cannot install both on one system and therefore I chose the BatterySmart.

This article swayed my decision to not install a BMV712: https://marinehowto.com/programming-a-battery-monitor/

To me the BMV-712 tells exactly how much fuel was taken from an "unknown" sized tank. The tank size is a moving target that starts smaller on a new battery, gets larger after some cycles, and then gets smaller-and-smaller thereafter. Sure I know my battery bank's Amp Hour rating, but I have no idea how many Amp Hours equals 50% discharge. The Victron 100/30 also gives me total watts produced each day, which when divided by 12.5 gives me an approximation of the Amp Hours used.

I like data. I like checking my Amp draws, monitoring my voltage, watching my solar wattage produced and the Amps being pushed into my batteries. I just feel that monitoring the voltage level of the battery is as good as knowing how many Amps I took out of it.

I started this thread to see the useful information others get from their solar systems. I've asked for screen shots from monitors. We are now nine pages into this thread and no one has posted a screen shot from a BMV-712. I have yet to see any evidence that installing a BMV-712 would have been better than installing the BatterySmart module.

Your thoughts?
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Old 10-05-2018, 04:36 PM   #126
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I’m pretty sure the Victron monitor being a “shunt “ device gives accurate data, Trimetric TM2030 absolutely does. It computes SOC and dozens of other points of interest on usage and net amps with your input as it is set up. It also gives you customizable charger setting with SC2030. It is far from a toy. I would never have solar without one; Bogart or Victron.
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Old 10-05-2018, 08:46 PM   #127
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Quote:
Originally Posted by AirMiles View Post
Bob said: You have to use some sort of current shunt based device if you want to have any idea of where you are. Knowing where you actually are *is* pretty important.

Bob & others, I'd like to explore this issue a little deeper. I have not been a proponent of installing a Victron BMV-712 or similar monitoring device. I chose to not install one. I'm sure its "cool" to have one as it provides lots of data. Its not that it doesn't provide accurate information. Its probably more because I think its a pain to install the shunt and I don't know where I would mount the shunt or the monitor. Its not that expensive if I really wanted one, but I just don't believe it provides enough useful information to be worth the effort and cost to install it. I chose to install the Victron BatterySmart module instead, which provides voltage compensation in addition to the temperature compensation of the BMV-712. I was told that you cannot install both on one system and therefore I chose the BatterySmart.

This article swayed my decision to not install a BMV712: https://marinehowto.com/programming-a-battery-monitor/

To me the BMV-712 tells exactly how much fuel was taken from an "unknown" sized tank. The tank size is a moving target that starts smaller on a new battery, gets larger after some cycles, and then gets smaller-and-smaller thereafter. Sure I know my battery bank's Amp Hour rating, but I have no idea how many Amp Hours equals 50% discharge. The Victron 100/30 also gives me total watts produced each day, which when divided by 12.5 gives me an approximation of the Amp Hours used.

I like data. I like checking my Amp draws, monitoring my voltage, watching my solar wattage produced and the Amps being pushed into my batteries. I just feel that monitoring the voltage level of the battery is as good as knowing how many Amps I took out of it.

I started this thread to see the useful information others get from their solar systems. I've asked for screen shots from monitors. We are now nine pages into this thread and no one has posted a screen shot from a BMV-712. I have yet to see any evidence that installing a BMV-712 would have been better than installing the BatterySmart module.

Your thoughts?


See my post #9 regarding images of the bmv output. The bmv in a full Victron system is the component that determines state of charge, which is displayed on the CCGX and the little BMV screen.

You cannot rely on voltage / temp to accurately determine SOC with lithium - you must do so based on energy flow to/from the batts. For that you must use a shunt.

The Victron smart battery sense module (I think that is what you are referring to) simply measures voltage and temperature at the terminals. Nothing more, nothing less. That in of itself is not very helpful in a lithium install to determine SOC and the appropriate charge currents.

For lead acid install it’s fine - but a shunt that monitors actual energy flow to/from the lead acid batts is still more accurate in determining SOC, and appropriate charge currents when configured and calibrated correctly.
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Old 10-05-2018, 09:39 PM   #128
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On my new KISS Lithium system I saw in real time why a shunt is a better way to determine SOC.
When the voltage drops on the lithiums it does so quickly with enthusiasm.😂

After 12hrs at high draw the voltage dropped very little, still 12.9v @ 40%.
Voltage not a good indicator for SOC with the BB's.

Bob
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Old 10-06-2018, 03:54 AM   #129
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Robert & Wulfraat,

I agree 100% that a battery monitor is required to determine SOC in a Lithium battery bank. Because my battery bank is lead-acid, I think in those "old-fashioned" terms. I am not ready to move to the more complicated lithium batteries, but like what Battle Born is doing to the reduce the complications. I appreciate the early adopters that are moving this technology forward.

The Victron BatterySmart module does two functions. It supplies real-time battery temperature and battery voltage (at the battery terminals) to the Victron Controller over bluetooth. Since my lead-acid batteries are in their original location on the tongue and my controller connections are to the positive and negative buss bars inside the Airstream, there is ample opportunity for voltage loss. If voltage loss occurs between the controller and the battery, the BatterySmart will communicate with the Victron controller to increase the voltage output until the battery is receiving the controller's programmed voltage. To me with my configuration, this real-time voltage adjustment is more important than knowing exactly how many Amps were removed from my batteries. I was told you cannot have a BMV-712 with a BatterySmart. The BatterySmart was designed for configurations where the batteries are in a remote location at differing temperatures than the controller location.

If my batteries were AGM and placed inside my Airstream, I would probably install the BMV-712 over the BatterySmart. In this case, voltage drop will not be an issue, with the shorter distance and fewer connections to the battery, and the controller will be at the same temperature as the batteries. Here a BatterySmart would not provide any useful functionality and the BMV-712 would provide more useful information.

It appears the one absolute with all solar and battery installations is that there are no absolutes. Each person needs to determine the best solution for their configuration. If your lead-acid batteries are remotely located the BatterySmart is a good option, in all other cases a BMV-712 is the better choice.
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Old 10-06-2018, 07:12 AM   #130
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Robert & Wulfraat,

I agree 100% that a battery monitor is required to determine SOC in a Lithium battery bank. Because my battery bank is lead-acid, I think in those "old-fashioned" terms. I am not ready to move to the more complicated lithium batteries, but like what Battle Born is doing to the reduce the complications. I appreciate the early adopters that are moving this technology forward.

The Victron BatterySmart module does two functions. It supplies real-time battery temperature and battery voltage (at the battery terminals) to the Victron Controller over bluetooth. Since my lead-acid batteries are in their original location on the tongue and my controller connections are to the positive and negative buss bars inside the Airstream, there is ample opportunity for voltage loss. If voltage loss occurs between the controller and the battery, the BatterySmart will communicate with the Victron controller to increase the voltage output until the battery is receiving the controller's programmed voltage. To me with my configuration, this real-time voltage adjustment is more important than knowing exactly how many Amps were removed from my batteries. I was told you cannot have a BMV-712 with a BatterySmart. The BatterySmart was designed for configurations where the batteries are in a remote location at differing temperatures than the controller location.

If my batteries were AGM and placed inside my Airstream, I would probably install the BMV-712 over the BatterySmart. In this case, voltage drop will not be an issue, with the shorter distance and fewer connections to the battery, and the controller will be at the same temperature as the batteries. Here a BatterySmart would not provide any useful functionality and the BMV-712 would provide more useful information.

It appears the one absolute with all solar and battery installations is that there are no absolutes. Each person needs to determine the best solution for their configuration. If your lead-acid batteries are remotely located the BatterySmart is a good option, in all other cases a BMV-712 is the better choice.
Hi

The MPPT + BMV712 can do exactly the same thing as the Battery Sense module. You can read battery temperature and feed it back to the rest of the system. If that's not what you wish, you can use the 712 independent of a Battery Sense module.

The example we were talking about with a heavily loaded inverter is a terrific one for showing why you need a shunt even with lead acid batteries. At least the Victron units will compensate for discharge rate on a lead acid and give you accurate "how empty" numbers. A voltage reading while under heavy discharge is pretty much useless for doing this.

I very much agree that mounting a shunt is a PIA. Getting it fit in was a non-trivial part of rewiring my trailer. Cost wise, if you are going with a "big" battery setup of any sort ... not a big deal. Not trivial, but also not into the "major" category.

Bob
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Old 10-06-2018, 07:45 AM   #131
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Bob, Both the BatterySense and BMV-712 do temperature compensation, but only the BatterySense does voltage compensation "at the battery". The BatterySense is connect to the battery terminals, it tests the voltage at the terminals, communicates the voltage (and temperature) back to the controller over bluetooth, and the controller adjusts its output to maintain the desired voltage at the battery. The BatterySense module is perfectly designed for using lead-acid batteries located in the Airstream's tongue. Without a BatterySmart, the controller outputs the desired voltage at its terminals but has no way to know the voltage level at the battery.

Directly from Victron: "By measuring voltage at the battery bank terminals, errors arising from voltage-loss due to cable resistance are avoided - guaranteeing the correct charge-voltage." Source: https://www.victronenergy.com/access...-battery-sense
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Old 10-06-2018, 09:46 AM   #132
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Hi

Ummm .... errrrr ... the 712 also connects direct to the battery, can do temperature measurement, and will Bluetooth network with a "Smart" MPPT to coordinate all of the readings. The Battery sense module is just a way to add the sense to the MPPT if you don't have a 712.

You can also network (like with cables) the whole thing together and get the job done that way. Normally you need some sort of central controller to get it all going.

There are a *lot* of ways to hook up a Victron system. Sorting them all out is not at all easy. They pretty much let you do anything anyway. Unfortunately there are a few exceptions to that so the sorting out process is needed. The manuals get written when the devices are brand new and are not updated quite as often as you might want. That also makes sorting things out a bit exciting ....( = read the firmware update notes ... ).

Bob
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Old 10-06-2018, 10:22 AM   #133
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It’s true that the closer the measuring device is to the batteries the better - less voltage drop. My system has the shunt within just 2’ of the batts, connected via a massive gauge cable - so I don’t see any voltage drop at the shunt by design.

I can definitely see the advantage of the smart sense if lead acid your batteries are far away from the voltage measuring device.

For lead acid the smart sense is a good / simple way to go for sure.
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Old 10-06-2018, 09:18 PM   #134
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Airmiles, sounds like you have the system that works for you, and again that matters. One of the thugs ain’t really like about the shunt system is the real-time m aside of amp draw. This has really helped me understand what each part of my electrical system uses.

It also is great to help notify you if you have left a light on somewhere you can’t see. I know what the amp draw is when in sleep mode. Several times I have seen more than normal as a check before I go to bed, and I can shut off that outside light, storage light etc.

Another cool feature is the BMV will,tell you how much time you have left at any given point when using devices. If you are cutting it close somewhere, it’s great to know how many days you can go if you use device a or device b.

Overall, if you are an information/data geek like me, there is much it shows that is useful. I love it, and play/look at it all the time. It has helped me understand my system, the drains, and also understand what I can expect for a given situation by looking at history. For example, if the past two days were cloudy, I can look at the net net power in and out, and no what to expect and how many days I can make it.

All of this allows me to make real,time decisions on what to use, how much I can recharge, etc.

I really like it. Do I have to have it. Not really. But it adds to the fun
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Old 10-07-2018, 09:34 AM   #135
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Thanks Trout, I liked hearing how you use the BMV-712 to improve your results. I frequently use my Amp meter to see what my draw is doing. I've turned on every appliance individually and recorded its Amp draw so I can attempt to manually do some of what the BMV-712 does. I like data too and check my solar screens several times per day to see how it is performing. A BMV-712 would add to my fun too.
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Old 10-12-2018, 07:53 AM   #136
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Here are detailed photos of how I connected my solar controller between the Airstream pre-wire and bussbars.
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2021 Northern-Lite 10-2 & F350 DRW PSD, 600W Solar/Victron/600A BattleBorn
146 nights 31,000 miles (first 10 months!)
Sold: 2018 GT27Q, 74 nights 12,777 miles
Sold: 2017 FC25FB, 316 nights 40,150 miles
Sold: 2013 Casita SD17 89 nights 16,200 miles
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Old 10-25-2018, 11:43 AM   #137
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Late season solar results

For the past 20 days we’ve been camping in some very challenging conditions for our solar powered Airstream. We started in Alabama in the shadows of hurricane Michael for the first several days, moved to a tree-canopied site in Mississippi for a few days, then moved on to central Texas for the past several days. We have seen very little sunshine on this trip. Overcast sky’s with rain have been the norm.

My 400W series/parallel system using the factory prewire has been working pretty well in the challenging conditions. I did use the generator a few hours to boost charge the batteries on the two days with 100W or less solar production. Temperatures have been around 50 degrees at night and near 60 daytime. My Airstream propane heater has been set at 68 degrees day and night and runs during the day. My wife used her hairdryer a few times on days where the minimum voltage levels were extremely low. Our typical low voltage after resting was always 12.1V or above. Another interesting data point is that our Airstream uses 120W of solar production to maintain its batteries while in storage as shown in the first ten days of the graph and few days of the data table.

Here are the output screens from my Victron 100/30 controller.
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2021 Northern-Lite 10-2 & F350 DRW PSD, 600W Solar/Victron/600A BattleBorn
146 nights 31,000 miles (first 10 months!)
Sold: 2018 GT27Q, 74 nights 12,777 miles
Sold: 2017 FC25FB, 316 nights 40,150 miles
Sold: 2013 Casita SD17 89 nights 16,200 miles
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Old 10-25-2018, 07:16 PM   #138
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Quote:
Originally Posted by waninae39 View Post
this is my setup with the same system parts except the solar panel.

i am waiting for a good a sunny day to install the solar on the roof

this is my 160W panel
http://www.heliene.ca/products/detai...,10,20,581,729
Curious, what is the device below the MPPT controller? It is blue like Victron equipment but I can’t see any markings on it.

Thanks,
Bill
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Old 10-26-2018, 10:11 AM   #139
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Quote:
Originally Posted by billrector View Post
Curious, what is the device below the MPPT controller? It is blue like Victron equipment but I can’t see any markings on it.

Thanks,
Bill
Hi

It appears to be one of their battery disconnect modules ( a BP-100 maybe). As shown in the picture it is not (yet) fully wired up.

Bob
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Old 11-06-2018, 01:35 PM   #140
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AirMiles

I first want to thank you for starting this thread. I have read through it completely and have learned a lot about solar through what others have done. Now having said that I am still very much a solar newbie as I have not used solar very much at all.

My first solar experience was to get a flexible 80 watt solar panel that came with a controller to power my Dometic compressor refrigerator that I carry in my car when I travel solo and at other times carry in my truck when traveling with the Airstream. I then looked at a thread you contributed to and first learned of the Victron Controller. I decided that I needed one of these, Victron 75/15), to use with my flexible panel to get more power and also to use when I added another 80 watt solar panel.

I initially didn’t plan on installing solar because we seem to never boondock long enough to run out of battery power. We have two inexpensive golf cart batteries, from Sam’s, that are 8 years old. These seem ok as we camped for a week in the Smokies without solar at all. Click image for larger version

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ID:	327213We also don’t seem to use much power, maybe I estimate about 10 amp hours per day. I just recently installed a Bogart Engineering battery meter but for the most part just used a volt meter to determine the state of charge of the batteries and how many amp hours we had used.

We decided to install solar so that we could camp longer and not be concerned with running out of battery power plus we learned that we could get some Grape 100 watt panels from HD for only $100 each with free delivery. We ordered 80 feet of #10 wire, some MC4 connectors, and hardware to tilt the panels. We decided on portable panels as we didn’t want all the complexity of installing them on the roof. We have spent about $650 total on the 400 watt portable system. We have just used it a couple of times and really only used 2 panels, connected in series. If we use all 4 panels we will operate in series/parallel as you have done. I am hoping the 75/15 controller is enough to handle it. I believe the voltage should be about 36 and the current less than 15 amps. Here are some photos.

Dan
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