battery monitor

[bottle]

No.

 

Just connect the two wires, one to opposite ends of the bank, where you take off cables already are.

 

Just one caveat, read the manual at least three times and understand what the Smartgauge tells you, just like all gauges.

Edited October 25, 2015 by bottle

[Scholar Gypsy]

Having both a Smartgauge and an AH counting gauge I have pretty good idea of the accuracy. Our batteries are currently operating at rated capacity and starting from fully charged, the Smartgauge and Mastershunt are within a few % of each other under a wide variety of discharge conditions. During fast charge Smartgauge lags the Mastershunt by quite a bit for a while, but by the time 100% is approaching they are both saying nearly the same thing.

 

Although we normally fully recharge each day, if we don't I tend to believe the Smartgauge over the Mastershunt (during discharge) as the former doesn't suffer from desynchronisation issues.

 

The Smartgauge really is surprisingly accurate considering how it works.

Thanks, that is indeed pretty accurate. Smartgauge is certainly an improvement on my previous method, which is to wait for the fridge to go on strike ..... Edited October 25, 2015 by Scholar Gypsy

[Arthur Brown]

Many people on boats are looking for the economy option, A simple voltmeter covers this and will certainly tell you little -but enough to save you the £20 or so that the meter costs -expressed in battery life.

 

IMO the best option on the market is the Smartgauge, two wires to connect and fit the display unit. SOC measurement as accurately as available on a display, at your fingertips.

 

Other systems exist, better solutions to the question will develop as the years proceed.

[Scholar Gypsy]

.....

 

Just one caveat, read the manual at least three times and understand what the Smartgauge tells you, just like all gauges.

That will mean reading one of the instructions six times, as it is deliberately duplicated ...

[Neil Smith]

Thanks for all the great advice as usual, I think for my needs and limited knowledge it might have to be the smart gauge, who can I get the best deal from.

 

Neil

[nicknorman]

I hate to ask a stupid question.

I have 3 batteries. Do I need 3 Smartgauges to measure each battery?

You need a Smartgauge to measure each bank of batteries. Most people just have one domestic battery bank (eg 3 batteries connected together) and one starter battery. The Smartgauge will thus tell you the SoC of the domestic bank, and just the voltage of the starter battery. Since the starter battery spends most of its time fully charged there seems no point in knowing its SoC.

[nb Innisfree]

If you go complicated with umpteen gauges and monitors and all, you will probably get confused, bamboozled, paranoid, forever checking, double checking, comparing, bothering everyone with questions, bags under the eyes with insomnia, tear your hair out, terrifying electrical phobias will set in, screamin abdabs will become the norm,, to be finally carted away by men in white coats.

 

Are you speaking from experience?

[nb Innisfree]

There's nothing simple about batteries, it's just that some accessories make it less complicated, but still complicated all the same.

[Laurie Booth]

You need a Smartgauge to measure each bank of batteries. Most people just have one domestic battery bank (eg 3 batteries connected together) and one starter battery. The Smartgauge will thus tell you the SoC of the domestic bank, and just the voltage of the starter battery. Since the starter battery spends most of its time fully charged there seems no point in knowing its SoC.

Cheers

No.

 

Just connect the two wires, one to opposite ends of the bank, where you take off cables already are.

 

Just one caveat, read the manual at least three times and understand what the Smartgauge tells you, just like all gauges.

Cheers

[blackrose]

Smartgauge.

 

Pity some of the other posters can't read your requirements! You say you are not very technical, but they come up with technical answers. Smartgauge is easy to install, requires no setting up (assuming normal battery type) and dead easy to use. I was going to say "dead easy to use and interpret" but really, no interpretation is required.

I more or less agree. If you're not very technically minded then you'll either need something that's easy to install yourself (smartgauge) or get someone in to install it for you. Any shunt-type monitors that read amps in/out, although useful, will require all battery negatives to be connected through the shunt, so it's not necessarily an easy installation.

 

I have a shunt-type monitor (BEP DC meter) and a smartgauge and they're both useful, but if I could only have one I'd probably keep the smartgauge.

 

No interpretation needed with s Merlin Powergauge, it gives you the voltage (easy) if you want the percentage used or left it will tell you that also (simple)

Except that it's not so simple because shunt-type monitors are notoriously inaccurate when it comes to SoC readings and do need interpretation. The most accurate gauge in terms of SoC is the smartgauge.

Edited October 25, 2015 by blackrose

[Paul C]

Merlin Powergauge is Smartgauge Mk.2, effectively.

[blackrose]

I know it's wrong, but I have real difficulty getting past the Smartgauge looking like a 1970s calculator!

Just think of it as trendy retro styling!

Merlin Powergauge is Smartgauge Mk.2, effectively.

Ah, I didn't know that. I retract my previous comment on it!

[nicknorman]

Merlin Powergauge is Smartgauge Mk.2, effectively.

No, I think that is something else.

Edit. You are thinking of the Datacell (which costs around £1k).

Edited October 25, 2015 by nicknorman

[Phil Ambrose]

No, I think that is something else.

Edit. You are thinking of the Datacell (which costs around £1k).

It doesn't really matter as the OP has already made his mind up and as for the rest of us, I think Simon hit the nail on the head by saying that you learn to know what is right.

Phil

Edited October 25, 2015 by Phil Ambrose

[ditchcrawler]

Victron ere, gives me soc and that's enough for a simpleton like I is

No it doesnt, it give you a guess at SOC that may or may not be correct

[Paul C]

No, I think that is something else.

Edit. You are thinking of the Datacell (which costs around £1k).

 

I keep forgetting. I did once get a price for it, and it was basically so much more than any other, that I put it to the back of my mind!!!! Its an interesting piece of technology (to combine shunt ammeter with the required algorithms to better estimate SoC) but offers nothing in terms of actual features, to eg NASA BM2 or Victron BMV702, just the promise that its better for undisclosed reasons. Its there and it exists, though.

 

What's a Merlin Powergauge then???- EDIT found some info on the internet, none the wiser what it is, or does, compared to the Merlin Datacell which seems to do exactly the same thing but differently/better(?) Maybe its a newer thing and they introduced it and cut out some of Datacell's features because it was so expensive? It seems to be a "simple" battery monitor which uses a shunt and does the usual Amp-hour counting; the Pro version has an interface to connect to a computer. I can't see what it does for £250 that the Victron doesn't for £150 though.

Edited October 25, 2015 by Paul C

[Top cat]

I agree the SOC figure my Victron gives is a work of fiction. Recently I let the batteries settle off load, measured the voltage and temperature, then using a temperature compensated chart worked out the SOC which was widely different from what the Victron was saying. I cross checked using the Ahr used vs the rated capacity and the chart was way closer than the Victron that was alledging that my 3 yr old batteries were now at 150% of their original capacity.

 

So for a quck at a glance indication of SOC use a Smartguage but read and understand the instructions.

For learning how to interpret how you batteries are doing use a volt and ammeter.

 

 

Top Cat

[MtB]

How is a Smartgauge affected by solar connected to the battery bank?

 

I've read two posts today, one claiming it copes well and the other saying solar confuses it.

 

Who here has a Smartgauge with a solar installation? DO you trust what it tells you about SoC?

[nicknorman]

I keep forgetting. I did once get a price for it, and it was basically so much more than any other, that I put it to the back of my mind!!!! Its an interesting piece of technology (to combine shunt ammeter with the required algorithms to better estimate SoC) but offers nothing in terms of actual features, to eg NASA BM2 or Victron BMV702, just the promise that its better for undisclosed reasons. Its there and it exists, though.

 

What's a Merlin Powergauge then???- EDIT found some info on the internet, none the wiser what it is, or does, compared to the Merlin Datacell which seems to do exactly the same thing but differently/better(?) Maybe its a newer thing and they introduced it and cut out some of Datacell's features because it was so expensive? It seems to be a "simple" battery monitor which uses a shunt and does the usual Amp-hour counting; the Pro version has an interface to connect to a computer. I can't see what it does for £250 that the Victron doesn't for £150 though.

I think the Powergauge is relatively old and nothing to do with Gibbo. Merlin probably bought the rights to it as they did with the Smartgauge some time later. The Datacell is their in-house product (in which Gibbo had a hand of course).

 

I think what the Datacell offers is not only accurate SoC, but also accurate indication of what the battery's capacity actually is at the moment. Something I get a bit cheaper by having a Smartgauge and the Mastershunt, plus some simple maths.

Edited October 25, 2015 by nicknorman

[peterboat]

i bought the nasa bm2 because i wanted to see what was going to the batteries and going out it also gives me a s o c and a voltage for the starter battery at 116 squids it was money well spent. i know what my inverter uses on standby etc. on a plus it shows me what amps the alternator is adding so i can set the lowest engine rpm for charging and hot water will a smartguage do any of that. and as solar is put through it i know how effective it is. also the smartguage seems to be more expensive for less information.

so maybe its spend less and get more from the bm2

Edited October 25, 2015 by peterboat

[Sea Dog]

i bought the nasa bm2 because i wanted to see what was going to the batteries and going out it also gives me a s o c and a voltage for the starter battery at 116 squids it was money well spent. i know what my inverter uses on standby etc. on a plus it shows me what amps the alternator is adding so i can set the lowest engine rpm for charging and hot water will a smartguage do any of that. and as solar is put through it i know how effective it is. also the smartguage seems to be more expensive for less information.

so maybe its spend less and get more from the bm2

Probably the nicest display on the NASA. I went for Victron for the bigger shunt mainly, otherwise the NASA may have been a good buy, particularly at the price.

 

 

Edited to remove double post

Edited October 25, 2015 by Sea Dog

[nicknorman]

.. it also gives me a s o c ...

 

so maybe its spend less and get more from the bm2

"A SoC" is the important point. Not "the SoC". It's quite a lot of money to spend on something that gives an imaginary SoC based on the presumption that the batteries actual capacity matches the manufacturer's stated new capacity.

 

So yes it does give you information about current flowing in and out, but its SoC reading may become very misleading as the batteries lose capacity which, in my experience, they will do within 6 months if they are normal leisure type. Or if you don't fully recharge the batteries to 100% SoC regularly.

 

The Smartgauge only gives SoC and battery voltage, but it does that better than anything else.

[peterboat]

"A SoC" is the important point. Not "the SoC". It's quite a lot of money to spend on something that gives an imaginary SoC based on the presumption that the batteries actual capacity matches the manufacturer's stated new capacity.

 

So yes it does give you information about current flowing in and out, but its SoC reading may become very misleading as the batteries lose capacity which, in my experience, they will do within 6 months if they are normal leisure type. Or if you don't fully recharge the batteries to 100% SoC regularly.

 

The Smartgauge only gives SoC and battery voltage, but it does that better than anything else.

i like the ability to see those amps and s o c seems to be working ok and my batteries are 10 years old so must be working to a point

[nicknorman]

i like the ability to see those amps and s o c seems to be working ok and my batteries are 10 years old so must be working to a point

Some friends of mine phoned me up to say that their lights were dim, pumps not working etc and yet the SoC on their meter (a BMV I think) was showing 80% SoC. When I got them to press the right button to see battery voltage it was showing 10v. Their batteries had deteriorated to the point they had little capacity, but the AH-counting gauge was blissfully unaware.

 

If you want to use a SoC meter to ensure you remain above about 50% SoC then as the batteries deteriorate the reading of 50% will occur at lower and lower actual SoC and by taking the SoC well below an actual 50% you of course hasten their demise.

 

You are saying that the meter works fine for you, but the point is that it won't be telling you the truth. If you are happy that the reading is fictitious then that is your prerogative, but it seems a lot of money to spend on an imaginary number generator (and an ammeter, I'll grant you).

Edited October 25, 2015 by nicknorman

[NB Lola]

No it doesnt, it give you a guess at SOC that may or may not be correct

Understood, but it is still enough for a simpleton like me, in my personal opinion.