Smartgauge w/ 3 batterys

[ayates]

A few features I would really like to see with the Smart Gauge are:

1. Ability to log state-of-charge over time.
2. Support fo a remote display.
3. LCD display for reduced power consumption.

Allan.

[conachair]

Originally Posted by ayates

A few features I would really like to see with the Smart Gauge are:

1. Ability to log state-of-charge over time.
2. Support fo a remote display.
3. LCD display for reduced power consumption.

Allan.

If they added a amp meter / counter then I'd certainly get one. As it is, it seems good at telling how full the bucket is but nothing at all about the size of the bucket or how much is going in or out.

[john61ct]

Merlin does have more recent releases, not labelled SmartGauge, likely worth a look.

[noelex 77]

I posted a review of the Simarine Pico monitor, which may be of some interest here:
http://www.cruisersforum.com/forums/...147499-78.html

[john61ct]

Originally Posted by conachair

If they added a amp meter / counter then I'd certainly get one.

Do you want accurate SoC?

For counting amps if not a second expensive less-accurate full-blown SoC, add a cheap maybe $20 AH counter.

Originally Posted by conachair

but nothing at all about the size of the bucket

Nothing measures that accurately but a proper 20-hour load test.

Which is what is periodically required in order to keep the shunt-based SoC meters accurate.

[john61ct]

Originally Posted by noelex 77

I posted a review of the Simarine Pico monitor, which may be of some interest here:
http://www.cruisersforum.com/forums/...147499-78.html

Wrong thread linked to there

[sailinglegend]

Originally Posted by conachair

If they added a amp meter / counter then I'd certainly get one. As it is, it seems good at telling how full the bucket is but nothing at all about the size of the bucket or how much is going in or out.

Your car fuel gauge just tells you how full the tank is so you decide when to top up.

SmartGauge will never add an amp meter because that will make the installation much more complicated and prone to errors. That comes directly from the MD James Hortop.

I would advise buying a cheap amp/Ah counter to know when and where your amps are flowing - but make sure it measures amps charging and discharging - not all do!

[conachair]

Originally Posted by john61ct

Do you want accurate SoC?

That's in the category of nice to have but not nice enough to actually spend money and find a place to put . As it is on board accurate voltage logging can spot trends much smaller than would be noticed just with a meter.

Nothing measures that accurately but a proper 20-hour load test.

Which is what is periodically required in order to keep the shunt-based SoC meters accurate.

Nope, but for a liveaboard cruising boat a single box which gave a decent accuracy of SOC & amp counting could be useful as a heads up that things aren't great in the battery land. If your overnight use is still at X amps but the SOC in the morning is getting lower each day then it might be near the end for the batteries. Doing a 20h test is pretty much impossible for a boat living on the hook.

[conachair]

Originally Posted by sailinglegend

Your car fuel gauge just tells you how full the tank is so you decide when to top up.

Car tanks don't get smaller as they get older.

SmartGauge will never add an amp meter because that will make the installation much more complicated and prone to errors. That comes directly from the MD James Hortop.

I would advise buying a cheap amp/Ah counter to know when and where your amps are flowing - but make sure it measures amps charging and discharging - not all do!

Think you missed the point a bit, on it's own a smartguage isn't enough for a cruising boat, if it had amp counting then it would be a useful single box to have onboard without anything additional to install. Looks like that isn't going to happen so guess I'll not be getting one then

[john61ct]

Originally Posted by conachair

As it is on board accurate voltage logging can spot trends much smaller than would be noticed just with a meter.

Links to inexpensive automated loggers that creates pretty graphs would be appreciated.

I'm guessing not too hard to base something on Arduino or Raspberry Pi

[sailinglegend]

Originally Posted by conachair

....Doing a 20h test is pretty much impossible for a boat living on the hook.

No its not - just do one battery at a time overnight and recharge immediately with the engine to about 85% then do the next one. Go into shore power asap to recharge all back to 100%. You should be recharging to 100% anyway every two weeks even when living on the hook which is what I have been doing for 13 years. My Lifeline AGM batteries are now 13 years old and still working.

[Stu Jackson]

Originally Posted by sailinglegend

>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>

Chris Gibson, who developed SG, used to work for Link Battery Monitors but was getting really frustrated with them because he spent most of his time on the phone explaining to his unhappy customers why their expensive BM was not working as they expected. A shunt based battery monitor relies on Battery Capacity, Peukerts discharge constant, and the battery Charge Efficiency. All these values are different for each installation, but more importantly they all change over time so the calculated value of State of Charge becomes more and more inaccurate. Add to that the “Charging Gotcha” problems of resetting the BM to 100% and you see why a new device was needed.>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Good info, thanks.

Re what I've called "The Gotcha" (and which I've often posted to my writeup about it and to Maine Sail's discussion) includes two other important functions not included in your paragraph above:

1. Charging voltage and
2. Charging current

Those are two of the three attributes that are programmed as default values and need to be changed to avoid a coulomb counter from stating full battery prematurely. The third is the CEF recalc, which some monitors do not allow for changing to manual vs. auto recalc. But changing these two to be above the float voltage and 1% instead of the default 2% will avoid declaration of full before Maine Sail's recommendation of 1% AT ABSORBTION VOLTAGE.

Please note that these features are completely different than the "problems of resetting the BM to 100%;" i.e., resetting the ah counter to zero or "Synchronization" on some Link products like the Link Lite.

This is detailed in my "Gotcha" presentation. Maine Sail also includes it in his, and my link to my "Gotcha" discussion includes a link to his, too.

[conachair]

Originally Posted by john61ct

Links to inexpensive automated loggers that creates pretty graphs would be appreciated.

I'm guessing not too hard to base something on Arduino or Raspberry Pi

No links I'm afraid, this is a home build. Though not that difficult with openplotter running on a Pi and a cheap but accurate 4 channel voltage sensor - ads1115.
Node-red does the recording into a sqlite database once a minute of everything, 3 thermometers on engine head, alternator & exhaust elbow. baro pressure, sog,cog. Openplotter makes it easy to connect the sensors and creates signalk with the data so easy to get at in node-red.

Really useful for spotting trends and things that just wouldn't be obvious otherwise. Haven't found a simple way to create the graphs yet though, sql is a bit long winded. Maybe it's time to learn a bit of PHP or python..

[Dockhead]

Originally Posted by conachair

Think you missed the point a bit, on it's own a smartguage isn't enough for a cruising boat, if it had amp counting then it would be a useful single box to have onboard without anything additional to install. Looks like that isn't going to happen so guess I'll not be getting one then

I don't think you really need all that information. Ramblinrod's method is perfectly adequate for most cruisers, in my opinion.

And Smartguage does almost everything you'd want a battery monitor to do.

But if for whatever reason you really did want to drill deeper, then I agree with you - you need at least amps - amps and voltage give very accurate SOC during charging, maybe most accurate from any method. I'm amazed the amp counting meters don't use this to recalibrate themselves. But likewise, this additional data would fill in ALL the gaps in what Smartguage knows.

If on top of that you want to COUNT the ps - well, why not?

[conachair]

Originally Posted by Dockhead

I don't think you really need all that information. Ramblinrod's method is perfectly adequate for most cruisers, in my opinion.

Trying to image being on a cruising boat (living on the hook of course ) that had nothing to display how many amps were going in or out of the batteries.... ahhh, the horror!!

And Smartguage does almost everything you'd want a battery monitor to do.

Err, not at all, I'm really not hugely bothered about the state of charge, getting to full most days somewhere to be getting obsessive. And I'll have a good enough guess anyway just looking at amps/volts. So it would bring pretty much nothing to the party. This party anyway.

But if for whatever reason you really did want to drill deeper, then I agree with you - you need at least amps - amps and voltage give very accurate SOC during charging, maybe most accurate from any method.

How do you do that? Certainly accurate as to when they're at full charge but on the way up it's very much guess imho, though after time you get a bit of a feel looking at volts/amps , even then temperature can make a difference.