Battery monitoring

[Cloudinspector]

Our boat is fitted with a sterling inverter and charging system including a digital monitor which is great and provides more info than I could ever need.

We have a shoreline connected at our base so no worries there.

Only problem is the monitor only works when the engine is running so when we are moored canalside I have no way of knowing what state of charge the batteries are in without starting the engine.

Is there anything I can fit which is on all the time and can just look at to keep an eye on the batteries.

[Proper Job]

Smartgauge link

 

(other battery state of charge monitors are available)

Edited October 16, 2012 by Proper Job

[bottle]

Smartgauge link

 

(other battery state of charge monitors are available)

 

but they are not as simple to set up and read, also not needing any adjustment over time.

 

 

 

 

One proviso, as with all monitoring equipment it does need to be understood what the instrument is telling you. (all in the manual)

Edited October 16, 2012 by bottle

[BargeeSpud]

If you want cheap & cheerful ultra basic, look here:

 

http://www.amazon.co.uk/Electrical-Caravan-Boat-Battery-Indicator/dp/B004TKZP8E

 

It will allow you to monitor both domestic & engine batteries from the looks of it. Failing that, I think I might have something similar which will only monitor 1 battery circuit, but I'll have to check to see if I still have it. If I do, I'll post a pic & if you're interested, you can have it.

Edited October 16, 2012 by Spuds

[Gibbo]

Only problem is the monitor only works when the engine is running...

 

Then it's wired up wrong and doesn't stand a hope in hell of doing anything even remotely close to what it's supposed to do.

[dmr]

If you want to "simply monitor the state of the batteries" then the Smarguage is the ONLY instrument that will do this!

 

A simply voltmeter is quite a bit cheaper but you will need to periodically turn EVERYTHING off, wait a wait (ideally Hours but a few minutes will just about do) and then measure the voltage, and then refer to a suitable voltage chart. To get a good estimate you will also need an accurate voltmeter that can measure to 1/10 volt or better. The smartguage give a Direct readout of percentage charge.

 

I spent three years messing about with a voltmeter as I did not believe that the smartguage could work, I eventually got one, and it does

 

..........Dave

[Cloudinspector]

Then it's wired up wrong and doesn't stand a hope in hell of doing anything even remotely close to what it's supposed to do.

 

Ah bobbins!!!

 

Smartgauge looks like a quality piece of kit.

So could I fit one in conduction with what's already there?

 

I meant conjunction ;-))

[bottle]

Yes, to fit it only requires two wires, one to the positive and one to the negative battery bank terminals.

 

They must be connected directly to the battery terminals and not pass go.

 

Have a look at the Smartgauge site and click on the technical link. (prepare to be surprised)

[Cloudinspector]

Time to get the credit card out then..........AGAIN :-((

[Chris Pink]

Time to get the credit card out then..........AGAIN :-((

 

Why not read what the man said first (post #5)?

[Cloudinspector]

Why not read what the man said first (post #5)?

 

I did, either way I need the flash the plastic as electronics are beyond me so would need to pay an electrician to check my current system.

[BargeeSpud]

If you want to "simply monitor the state of the batteries" then the Smarguage is the ONLY instrument that will do this!

 

A simply voltmeter is quite a bit cheaper but you will need to periodically turn EVERYTHING off, wait a wait (ideally Hours but a few minutes will just about do) and then measure the voltage, and then refer to a suitable voltage chart. To get a good estimate you will also need an accurate voltmeter that can measure to 1/10 volt or better. The smartguage give a Direct readout of percentage charge.

 

I spent three years messing about with a voltmeter as I did not believe that the smartguage could work, I eventually got one, and it does

 

..........Dave

Not sure that is what the OP wants, I get the feeling he wants to simply look to see what the current voltage is with the engine off rather than a full break down of their current state to within a 1/10thV state of accuracy.

 

I'm probably wrong, so in that case, ignore my earlier post!

[Cloudinspector]

Not sure that is what the OP wants, I get the feeling he wants to simply look to see what the current voltage is with the engine off rather than a full break down of their current state to within a 1/10thV state of accuracy.

 

I'm probably wrong, so in that case, ignore my earlier post!

 

You're correct spuds. When we are sat canalside using power, lights, laptops, phone charging etc I want to be able just to look at a gauge which will tell me the state of discharge, preferably a %,

Obviously I need to get the wiring checked on the system we have but I may buy a smartgauge as well. Belt and braces so to speak. The longer I can prolong the life of my battery bank the better. £150 doesn't seem a bad investment considering £500+ to replace the batteries.

 

We are relatively new to narrowboats by the way and it's been a steep learning curve but love every minute of it. .

[Chalky]

 

£150 doesn't seem a bad investment considering £500+ to replace the batteries.

 

 

£150 to move a wire! As Gibbo says it sounds like your existing battery monitor is wired incorrectly. I suspect that they've tried to pick up a battery connection from the back of the ignition switch (rather than adding the extra wire) and have picked up a switched feed rather than a permanent one.

 

If all you've got is a volt meter then they've done it to prevent the meter flattening the battery over a period of time. If it's a proper battery monitor then its wire wrong.

[BargeeSpud]

I may buy a smartgauge as well. Belt and braces so to speak. The longer I can prolong the life of my battery bank the better. £150 doesn't seem a bad investment considering £500+ to replace the batteries.

 

We are relatively new to narrowboats by the way and it's been a steep learning curve but love every minute of it. .

That's a decision only you can make, if something like that will give you the peace of mind you want, then go for it. You will find, as your experience of our wonderful canal world grows, that nothing is totally wrong or right, it all usually boils down to what works for you. In this particular case, I'd say that the route you're swaying towards is probably the best one for you. There's nothing wrong with belts & braces, better than a wing & a prayer!

 

I'll tell you something else though, the steep learning curve merely gets shallower as your experience matures. It never disappears!

 

[Cloudinspector]

£150 to move a wire! As Gibbo says it sounds like your existing battery monitor is wired incorrectly. I suspect that they've tried to pick up a battery connection from the back of the ignition switch (rather than adding the extra wire) and have picked up a switched feed rather than a permanent one.

 

If all you've got is a volt meter then they've done it to prevent the meter flattening the battery over a period of time. If it's a proper battery monitor then its wire wrong.

 

It's a proper battery monitor not a voltmeter.

Sterling alt to batt 160-210 digital charger

2500w pure sine wave inverter

With a remote digital display like this

 

http://www.sterlingpowerproductsbam.co.uk/images/product/page21/pm-panel.gif

 

If I knew which wire to move I'd do it myself but I'm more likely to melt the whole system.

[matrix]

You're correct spuds. When we are sat canalside using power, lights, laptops, phone charging etc I want to be able just to look at a gauge which will tell me the state of discharge, preferably a %,

Obviously I need to get the wiring checked on the system we have but I may buy a smartgauge as well. Belt and braces so to speak. The longer I can prolong the life of my battery bank the better. £150 doesn't seem a bad investment considering £500+ to replace the batteries.

 

We are relatively new to narrowboats by the way and it's been a steep learning curve but love every minute of it. .

 

 

this might be what your looking for

http://www.victronenergy.com/battery-monitors/bmv-600s%20and%20bmv-602s/

ive used this for 4 years now ( older version )

and could highly recomend it

[Grace and Favour]

Yes, to fit it only requires two wires, one to the positive and one to the negative battery bank terminals.

 

They must be connected directly to the battery terminals and not pass go.

 

Have a look at the Smartgauge site and click on the technical link. (prepare to be surprised)

 

I'll second the above comments

 

I know that like any piece of equipment will have its supporters and critics

 

But I, (and more importantly me missus!) rate the Smartguage very highly, (and for Jo to have peace of mind and confidence is worth much more than £150 IMO)

[Chris Pink]

I did, either way I need the flash the plastic as electronics are beyond me so would need to pay an electrician to check my current system.

 

it's not a matter of electronics. One wire needs moving

 

http://www.sterlingpowerproductsbam.co.uk/images/downloads/PMP1_%20A5_2006a.pdf

 

page 6; the wire on the far right (marked plus +) is wired to (probably) to the ignition switch.

 

Wherever it is wired, move it to your domestic fusebox.

 

If you feel capable of wiring a smartgauge (2 wires) you can probably solve this issue (1 wire)

 

ps you cannot, by moving this wire, destroy anything.

 

although if you really want to spend money, please feel free.

[smileypete]

I spent three years messing about with a voltmeter as I did not believe that the smartguage could work, I eventually got one, and it does

Did you feel the voltmeter readings were close enough for practical purposes, or that the greater accuracy of the Smartgage was definitely necessary?

 

Smartgauge works for sure, I think in the longer term it's still helpful to understand some what the volt and amp readings mean, if only to help with problem solving.

 

cheers,

Pete.

[dmr]

Did you feel the voltmeter readings were close enough for practical purposes, or that the greater accuracy of the Smartgage was definitely necessary?

 

Smartgauge works for sure, I think in the longer term it's still helpful to understand some what the volt and amp readings mean, if only to help with problem solving.

 

cheers,

Pete.

 

Hello Pete,

 

We have an Adverc DCM so I was looking at the volts and amps and trying to make a mental correction to get an estimate of battery voltage.

Variable resistance in the isolator sometimes made this a bit awkward.

From time to time I would turn everything off for ten minutes to get a true battery voltage (10 mins get pretty close)

My laptop has a crap battery so after 10 mins it would be flat and need a reboot!

Also a couple of times I forgot to turn the fridge back on which did not go down too well.

 

I was really doing a minimal version of smartguage in my head!

When we got the Trojans I thought it was time to get a smartguage and do it properly.

£120 for a smartguage is not too bad against £500 for the batteries.

Smartguage is not perfect by any means, but as an engineer I really do admire what Gibbo has done here.

 

 

What I like most is that when the smartguage starts reading less than I expect I know its probably time for a bit of equalisation!

(Smartguage plus amp-hours would be even better for this.)

I am thinking about getting 4 more Trojans this winter and trying your idea of a "semi split bank" to make the equalisation less of an issue.

 

........Dave

[smileypete]

What I like most is that when the smartguage starts reading less than I expect I know its probably time for a bit of equalisation!

(Smartguage plus amp-hours would be even better for this.)

I am thinking about getting 4 more Trojans this winter and trying your idea of a "semi split bank" to make the equalisation less of an issue.

Think I'd rather try it out with someone's cast-off leisure batts first; switch the loads to them while the eq. is being done, then switch the loads back and charge up the second bank somehow.

 

Found something interesting on Ebay last night, 600W 10A current limiting boost converter, could be just the thing for eq'ing from another batt or power source:

 

http://www.ebay.co.uk/itm/180977778661

http://www.aliexpress.com/item/DC-DC-600W-10-60V-to-12-80V-Boost-Converter-Step-up-Module-Power-Supply-In/627127378.html

 

cheers, Pete.

~smpt~

[dmr]

Hello Pete

 

Have somewhat taken this thread off topic....but:

 

The split bank plan is still evolving but does not need a DC-DC converter.

1 Run bank as a single bank for two weeks or so to benefit from a very big bank

2 Split banks, use bank A and only connect bank B whilst charging so that over a few days it really does get to 100% charge

3 Split Banks, use bank B and connect bank A only whilst charging.

4 Revert to big paralllel bank

 

Advantages are:

Big bank

No 8 hour engine run needed to get to 100%

Much less high voltage equalisation needed that probably reduces battery life.

 

Shoot me down in flames if you want, I can take it!!!

 

I am using the smaller version of that DC-DC converter module for various things, including my 24v engine thermocouple read-out,

but that 600W jobbie looks suspect to me. I see no heatsinks, so assuming 90% efficiency can that TO220 really can shut of 60 Watts????

 

......Dave

[Paul C]

Yes, to fit it only requires two wires, one to the positive and one to the negative battery bank terminals.

 

They must be connected directly to the battery terminals and not pass go.

 

Have a look at the Smartgauge site and click on the technical link. (prepare to be surprised)

 

I've highlighted the middle bit of your post. I am interested in a Smartgauge too, but as I understand it, anything connected to the battery either needs to be connected via a fuse or circuit breaker. And unless its on the 'list' of devices which can remain connected (for BSS requirement), needs to go through an isolation switch too. I believe the only exceptions to this are the starter motor and the alternator (and even then, people suggest that in an ideal world, these should be appropriately fused too).

 

So, can you REALLY connect a Smartgauge DIRECTLY to battery terminals, and still meet the BSS requirements to the letter?

[dmr]

I've highlighted the middle bit of your post. I am interested in a Smartgauge too, but as I understand it, anything connected to the battery either needs to be connected via a fuse or circuit breaker. And unless its on the 'list' of devices which can remain connected (for BSS requirement), needs to go through an isolation switch too. I believe the only exceptions to this are the starter motor and the alternator (and even then, people suggest that in an ideal world, these should be appropriately fused too).

 

So, can you REALLY connect a Smartgauge DIRECTLY to battery terminals, and still meet the BSS requirements to the letter?

 

The BSS correctly recognises that some equipment should be connected directly to the batteries and Never switched off.

Bilge pumps are a good example!!!

I am not aware that there is a formal list of such equipment.

As long as they are individually fused then its fine.

There might be some confusion about whether this fuse should be inside or just outside the battery box, just outside probably keeps everybody happy!

 

..........Dave