Battery Monitors

[hbn7hj]

Didn't want to pollute the other thread. Booster mentioned the average RVer knows or cares very little about his batteries.

Gotta agree with him. Very few are interested in battery monitors. I did talk three friends into Trimetrics, one with a masters degree in Solar power. None of them get much info from their monitors. They use them as a fuel gauge and are happy to have them.

They have no clue that charging an AGM battery from 90%, 140 watts or so, from a 2.8kw or 4kw generator is a fools errand. They don't care, either.

They don't have solar so the only way they get to 100% is a week or so of shore power at 13.7 volts from the converter. They aren't off gridders so it happens often enough.

[Mfturner]

Have you ever heard of the Balmar Smart Gauge?

The marinehowto.com guy wrote highly of it a while ago, being shunt-less it would be very easy to install. I have no idea what it is actually doing unless it is closely watching dv/dt, modeling the battery as a huge cap to infer current. You'd need a very low noise measurement, better than mV, for estimating dv/dt for LFP batteries, but battery voltage changes slowly in the scheme of things, so maybe a huge amount of low pass filtering (e.g over sampling by averaging) can buy enough resolution. And then maybe it is just comparing measured voltages against tables, and using that for speculating SOC.

[GeorgeRa]

My first battery monitor was the famous Link10, way before the company was acquired by Xantrex in 2003. With its red LED display, it looked like one of the first digital watches by HP, but fortunately it was successful, not like HP’s fiasco. It seems as an item “you can’t leave home without it” As far as I know the Link 10 was the first company using Peukert’s parameter to calculate Ah balance.

My current favored is Victron or BlueSea with OLED display but have Magnum which is just OK.

http://www.xantrex.com/documents/Dis...-01_rev-A).pdf

[InterBlog]

We are one of the apparent few who are using an Electrodacus in a mobile capacity (as opposed to being in a fixed facility). There is basically no piece of data that this thing does not issue forth. I confess that I mostly use it as a fuel gauge, and to verify that the lithium cells are properly balanced. But there's a wealth of other utilization info in the thing should I ever develop a lifestyle that affords me the time to make such learning a higher priority.

[Phoebe3]

InterBlog, is that in a drawer that you can pull out and put away? Brilliant. And I wish all of our scattered bits were together in one place and a clearly labeled...

[booster]

Originally Posted by Mfturner

Have you ever heard of the Balmar Smart Gauge?

The marinehowto.com guy wrote highly of it a while ago, being shunt-less it would be very easy to install. I have no idea what it is actually doing unless it is closely watching dv/dt, modeling the battery as a huge cap to infer current. You'd need a very low noise measurement, better than mV, for estimating dv/dt for LFP batteries, but battery voltage changes slowly in the scheme of things, so maybe a huge amount of low pass filtering (e.g over sampling by averaging) can buy enough resolution. And then maybe it is just comparing measured voltages against tables, and using that for speculating SOC.

There have been several discussions on the forum about the Smart Gauge. They should show up in a search. I don't know if anyone really knows how accurate they are, or not, at this point.

[booster]

Originally Posted by GeorgeRa

My first battery monitor was the famous Link10, way before the company was acquired by Xantrex in 2003. With its red LED display, it looked like one of the first digital watches by HP, but fortunately it was successful, not like HP’s fiasco. It seems as an item “you can’t leave home without it” As far as I know the Link 10 was the first company using Peukert’s parameter to calculate Ah balance.

My current favored is Victron or BlueSea with OLED display but have Magnum which is just OK.

http://www.xantrex.com/documents/Dis...-01_rev-A).pdf

I don't recall if you were in on some of the discussions of Peukert and how, and if, it should be applied to RV batterey monitors. There was a very good discussion, I think.

I agree, it is an absolute necessity if you care about taking care of your batteries, but as Harry said, very few people really want to make the effort and just accept the shorter battery life.

[booster]

I think that as of now, unless some stuff has come out I haven't seen, the one thing I would really like to see from the battery monitors would be more usable output controls. Victron and Blue Sea both have a relay out connection, but it is very low current so can't directly run control relays very well.

It would be really nice for those of us that have multiple charging sources to be able to control them easily from the monitor outputs.

A system like the do in industrial PLC controllers could be done pretty readily, I think, using very low power signals from the monitor to control matching relay modules.

Unfortunately, it will likely never happen as the trend seems to be towards fully integrated controls the include the monitor functions like the Volta, or even the claim you don't need a monitor in your system like Roadtrek.

[InterBlog]

Originally Posted by Phoebe3

InterBlog, is that in a drawer that you can pull out and put away? Brilliant. And I wish all of our scattered bits were together in one place and a clearly labeled...

It's a plate held on with neodymium magnets. Pull from the two handles and it detaches, revealing all the glorious guts and wiring behind.

My husband has an obsession with ordering 3-D printed and laser cut parts online. For this one, he first ordered his prototype out of cheap plastic (about $30). Once it was confirmed that all these components fit, he had it re-done in this metal.

Among the DIY community, there were some concerns that the Electrodacus would not prove to sufficiently rugged for this application. Knock wood, it's been over a year and it has traveled cross-country, working perfectly the entire time.

[BBQ]

.

That's interesting.

That's DIY in another dimension that I have never explored.

Do you have any links? forums? etc., that I can check out?

[InterBlog]

Originally Posted by BBQ

.

That's interesting.

That's DIY in another dimension that I have never explored.

Do you have any links? forums? etc., that I can check out?

Regarding ours, you mean?

Well, there's the Thread from Hell here which describes the chat that took place as our system was being scoped and designed. I describe that thread in nadir terms because it has 500 comments and is an inefficient read. Plus, some of the information has been OBE (overcome by events) and is no longer accurate. None of these user forums allow authors to go back and post corrections.

I'm in the process of distilling the design information into a series of four concise blog posts of which I've only gotten two done so far because I keep getting distracted by other mods that I want to do (here are the first and second posts).

[BBQ]

Originally Posted by InterBlog

Regarding ours, you mean?

Well, there's the Thread from Hell here which describes the chat that took place as our system was being scoped and designed. I describe that thread in nadir terms because it has 500 comments and is an inefficient read. Plus, some of the information has been OBE (overcome by events) and is no longer accurate. None of these user forums allow authors to go back and post corrections.

I'm in the process of distilling the design information into a series of four concise blog posts of which I've only gotten two done so far because I keep getting distracted by other mods that I want to do (here are the first and second posts).

You guys are very smart.

Thanks.

[GeorgeRa]

Originally Posted by InterBlog

We are one of the apparent few who are using an Electrodacus in a mobile capacity (as opposed to being in a fixed facility). There is basically no piece of data that this thing does not issue forth. I confess that I mostly use it as a fuel gauge, and to verify that the lithium cells are properly balanced. But there's a wealth of other utilization info in the thing should I ever develop a lifestyle that affords me the time to make such learning a higher priority.

Is the Electrodacus current measurment based on a shunt?

[InterBlog]

Originally Posted by GeorgeRa

Is the Electrodacus current measurment based on a shunt?

I'll have to ask my husband lest I say the wrong thing. My husband's P.E. license is in mechanical engineering but in studying up on this project, he was processing a lot of electrical engineering content. His knowledge far outstrips mine.

The inventor of the Electrodacus, Dacian Todea, made all of his content open source, so the answer is likely there, too. Dacian funds himself with rounds of hardware sales on Kickstarter.

[gregmchugh]

Originally Posted by GeorgeRa

Is the Electrodacus current measurment based on a shunt?

I appears that there is a connection for a shunt on this device. See page 13...

http://electrodacus.com/SBMS100/manual/SBMSmanual.pdf

[GeorgeRa]

Originally Posted by gregmchugh

I appears that there is a connection for a shunt on this device. See page 13...

http://electrodacus.com/SBMS100/manual/SBMSmanual.pdf

Thank you, this device is way more than just a battery monitor which can justify 43 pages manual. Well, it comes with the Li territory.