Jump to content

Battery


jddevel

Featured Posts

30 minutes ago, nicknorman said:

Our Trojans require no mollycoddling except for watering a couple of times a year. But then we do use our boat as boats are intended to be used - for daily cruising, not as a cheap substitute for a house. <taking cover> So they rarely get less than 8 hrs charging a day, and of course on shore power when we are in the house. So far they have been vastly better than the cheapies we had previously.

Its not about the daily cruising its about the daily charging. I am not going back to living in a house thats far too boring. If I do buy another house which I could if I wanted I would do the sensible thing again and live still on the boat and holiday in the house.

Link to comment
Share on other sites

The whole purpose of the SmartGauge was and remains to give you a simple to understand guide as to how far your batteries are discharged. The manual and web site have always said not to rely on either SmartGauge or an Ah counter to determine 'fully charged' but to use some other means (tail current or Relative Density). 

When Smartgauge tells you that you are approaching 50% on that day it is a sign that you should start charging, turn everything off, or both. 

As for the definition of 'every discharge' that is indeed a difficult one to answer. When I tried to pin Trojan down as to what DoD they would consider the minimum before a recharge is required they simply repeated to charge after every discharge. I guess a sensible compromise which seems to work for the majority of boaters is 'daily'. 

45 minutes ago, Mike the Boilerman said:

 

I have seen many mentions over the years of how the SmartGauge was originally designed by Gibbo as a simple and easy to use 'fuel gauge' for his wife

 

 

Link to comment
Share on other sites

45 minutes ago, mrsmelly said:

Its not about the daily cruising its about the daily charging.

Surely they're the same thing? If you're cruising then you're charging with the alternator. 

Link to comment
Share on other sites

3 minutes ago, WotEver said:

Surely they're the same thing? If you're cruising then you're charging with the alternator. 

As well you know my reply was directed at Hobby boater Nick who thinks ownership of a house and a boat simply means you live in a house and hobby the boat which is in my opinion the wrong way round :P

Link to comment
Share on other sites

11 minutes ago, mrsmelly said:

As well you know my reply was directed at Hobby boater Nick who thinks ownership of a house and a boat simply means you live in a house and hobby the boat which is in my opinion the wrong way round :P

:cheers:

Link to comment
Share on other sites

1 hour ago, Mike the Boilerman said:

My batteries went wrong because I interpreted this literally and sized my batteries so it would take a week to run them down to 50%, at which point I would recharge them. Unfortunately I relied on the SmartGauge to tell me when they reached 100%, which as we all now know, is wrong.

In addition, I failed to 'recharge after every discharge' because the boat (and the battery bank) is in continuous use as a liveaboard, so the term is rather meaningless unless it means I need to start the genny every time the fridge motor shuts off. And somehow I think the Trojan advice DOES mean this. So now there are two things I'm doing wrong. 

This is exactly how I have been using my batteries. I typically take them down to around 60% ish and then will run the engine or genny to bring them back up to as full as I possibly can within the time available. With solar doing it's bit each day to put back in a bit each day.

This is the only feasible way to live in my situation.

I won't be buying expensive Trojans next time as I now realise that they ain't up to this usage scheme either; so I may as well ruin cheap batteries.

I do still like the smartgauge though, hassle free, assuming it's working properly.

Link to comment
Share on other sites

38 minutes ago, WotEver said:

When Smartgauge tells you that you are approaching 50% on that day it is a sign that you should start charging, turn everything off, or both. 

 

 

Aha, another new parameter I've not seen mentioned before!!

And in what way is it helpful to know one is approaching 50% (as opposed to 40%, or 60%) given the need to recharge daily regardless of the SoC, and the fact that occasional deep discharges are no bad thing?

A voltmeter would give equally accurate information, given one of my SmartGauges say 69% when the other reads 50%. 

1 minute ago, sirweste said:

I do still like the smartgauge though, hassle free, assuming it's working properly.

 

A risky assumption, in my opinion.

Link to comment
Share on other sites

3 minutes ago, Mike the Boilerman said:

And in what way is it helpful to know one is approaching 50% (as opposed to 40%, or 60%) given the need to recharge daily regardless of the SoC

Because it might only be say 2pm and you might not have intended to charge that day. Smartgauge is letting you know that you ideally need to start charging now and/or switch everything off. 

Link to comment
Share on other sites

5 minutes ago, Mike the Boilerman said:

A voltmeter would give equally accurate information

No it wouldn't. A voltmeter could well display 12.1V when the SoC is still 60%. It all depends on the loads.

That's the single difference between SmartGauge and a voltmeter. It's not intended for folk with experience who understand exactly what their other monitors are telling them. 

8 minutes ago, Mike the Boilerman said:

one of my SmartGauges say 69% when the other reads 50%. 

You've been told enough times to get them fixed. Pointlessly repeating that yours are faulty achieves nothing other than making you look silly. 

Link to comment
Share on other sites

2 hours ago, Mike the Boilerman said:

I have seen many mentions over the years of how the SmartGauge was originally designed by Gibbo as a simple and easy to use 'fuel gauge' for his wife. She was only told to keep the SmartGauge above 50%. I don't remember any corollary for her to recharge after every discharge ever being mentioned.

From the smartgauge website(for deep cycle batteries):-

 

"This is a rule that states quite simply, the most economical use of deep cycle batteries comes about when they are, on average, discharged to 50% capacity then recharged. "

 

http://www.smartgauge.co.uk/50percent.html

 

Next question, What is a deep cycle battery?

 

From Trojan(user guide):-

 

"Do not discharge your battery more than 80%. This safety factor will eliminate the chance of overdischarging and damaging your battery."

Edited by rusty69
Link to comment
Share on other sites

27 minutes ago, Mike the Boilerman said:

 

A risky assumption, in my opinion.

My gauge seems to read and thus display volts correctly for a quick check I did a while back. So the current claimed issue of p.d. calibration issues doesn't seem to apply to mine. 

It does however seem to be woefully inept at 100%. After a week (I was on me hols) of only the only thing supplied with power being the goat switch for the bilge pump the 200 W solar will have definitely got the bank to 100%. It did read 100% when I returned but this dropped to 90% after about 5 minutes of light power use

Link to comment
Share on other sites

5 minutes ago, rusty69 said:

Lucky you. How many haven't checked though and are living in ignorant bliss? 

By virtue of the fact that they haven't checked we'll never know. It could be a couple or it could be a couple of hundred. 

Link to comment
Share on other sites

Just now, WotEver said:

By virtue of the fact that they haven't checked we'll never know. It could be a couple or it could be a couple of hundred. 

I contacted merlin re my gauge as a result of your/mtb thread.

Initially they said send it back for calibration. When I said I no longer had the receipt and on giving them the serial number they said it was an old unit and they would  get back to me.

 

That was nearly two weeks ago.... 

Link to comment
Share on other sites

27 minutes ago, rusty69 said:

I contacted merlin re my gauge as a result of your/mtb thread.

Initially they said send it back for calibration. When I said I no longer had the receipt and on giving them the serial number they said it was an old unit and they would  get back to me.

 

That was nearly two weeks ago.... 

Not good enough, chase 'em :)

Link to comment
Share on other sites

1 hour ago, WotEver said:

You've been told enough times to get them fixed. Pointlessly repeating that yours are faulty achieves nothing other than making you look silly. 

Even if I sent BOTH FAULTY SMARTGAUGES back for repair, I'd still keep mentioning it because 

1) people need to know you can't rely on. Smartgauge straight out of the box, and

2) I'm winding you up and I'm surprised you haven't twigged this ;). You are however, shockingly quick to leap to the defence of the smartgauge when even the slightest criticism appears on this board, presumably because  you are best mates with the designer. 

Link to comment
Share on other sites

3 minutes ago, Mike the Boilerman said:

Even if I sent BOTH FAULTY SMARTGAUGES back for repair, I'd still keep mentioning it because 

1) people need to know you can't rely on. Smartgauge straight out of the box, and

Go Mike! i'm with you 100 percent on this, or is it 80 percent!

  • Greenie 1
Link to comment
Share on other sites

3 hours ago, jddevel said:

Seadog. Have a 240v fridge and was considering as suggested in another topic a small second inverter just for the fridge but it was pointed out that this second inverter due to its "quality" may use as much "resting" power as my Victron anyway

Ah yes, so you did, and the Victron is good kit. I'd agree duplication, particularly with an inferior product, is false economy. As long as you have a 240 volt fridge, just leave the Victron to do its work, but bear in mind that it will represent a small but continuous draw even when no 240v appliances are actually drawing current and factor that into any power audit type calculations. The Mastervolt manual contains all the relevant figures and I'm sure the Victron manual will too, so download that if you don't already have it. Several reads might make other things a bit clearer too, but I confess I had to read mine a few times to really get my head around it and I'm a Chartered Engineer! 

Good luck - I hope you're getting a clearer idea of your needs.

3 hours ago, jddevel said:

 

 

Edited by Sea Dog
Remove duplicate post
Link to comment
Share on other sites

20 minutes ago, Mike the Boilerman said:

You are however, shockingly quick to leap to the defence of the smartgauge when even the slightest criticism appears on this board, presumably because  you are best mates with the designer. 

That's completely untrue. Please show me a single post where you think I have done so. 

I will correct misinformation when it's offered and I'll explain for the umpteenth time what SmartGauge does and doesn't do but I wouldn't and never have 'defend' it against valid criticism. 

Link to comment
Share on other sites

Perhaps what people are overlooking is that boating is a rather usual application for a battery.

The vast majoroty of batteries are used in standby applications,  motive power or engine starting. In each case it is usual to fully recharge the battery after every discharge.

Domestic batteries on boats are rarely, if ever, fully recharged after every use.

As stated earlier in the thread, if you want maximum battery life recharge fully after every discharge, however small.

However in practice this is unrealistic, so the best one can do is charge as fully as convenient daily, and fully charge weekly. Solar helps a lot with this in the summer.

Link to comment
Share on other sites

54 minutes ago, cuthound said:

Perhaps what people are overlooking is that boating is a rather usual application for a battery.

The vast majoroty of batteries are used in standby applications,  motive power or engine starting. In each case it is usual to fully recharge the battery after every discharge.

Domestic batteries on boats are rarely, if ever, fully recharged after every use.

As stated earlier in the thread, if you want maximum battery life recharge fully after every discharge, however small.

However in practice this is unrealistic, so the best one can do is charge as fully as convenient daily, and fully charge weekly. Solar helps a lot with this in the summer.

That sums up the problem nicely,My Battery Bank is 6  105 AH unit but can be split into 2 Banks of 3,either Bank can power the Boat's Domestic requirements

The 'idle 'Bank can be  fully topped up with a 230v. Charger powered by the 'Working' Bank which allows a full 100 % charge  which can take up to 12-14 Hours to achieve .

When the charge is complete the Banks can be swapped over allowing the first bank to get the same treatment

This process can be carried out When Underway or when moored up and be supplemented by Solar Array or onboard Generator

Link to comment
Share on other sites

6 minutes ago, cereal tiller said:

The 'idle 'Bank can be  fully topped up with a 230v. Charger powered by the 'Working' Bank which allows a full 100 % charge  which can take up to 12-14 Hours to achieve .

That reads to me that you charge one bank from the other, i'm sure that isn't the case.What am I missing (maybe a brain?)

Edited by rusty69
Link to comment
Share on other sites

7 minutes ago, rusty69 said:

That reads to me that you charge one bank from the other, i'm sure that isn't the case.What am I missing (maybe a brain?)

Yes that's what he's doing. Less efficient in terms of Ah used but more efficient in terms of FULLY charging the batteries. 

Link to comment
Share on other sites

1 minute ago, WotEver said:

Yes that's what he's doing. Less efficient in terms of Ah used but more efficient in terms of FULLY charging the batteries. 

Oh, I'm gonna have to sit in a darkened room for a while and think about that (and how its affected by Peukert)

 

I may be some time..........

Link to comment
Share on other sites

29 minutes ago, rusty69 said:

That reads to me that you charge one bank from the other, i'm sure that isn't the case.What am I missing (maybe a brain?)

Yes Rusty,the bank receiving the Full charge is 'off line' and is charged by the Bank 'in service",I usually do this when both bank are fairly well charged after an several hours of Engine running(when boat is Underway)

The Bank receiving the full charge is only taking a few Amps. at engine shutdown so it is Isolated and then connected to the  230V Battery Charger(powered by the Boat's Inverter),usually over night

Does that make sense now? 

Edited by cereal tiller
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.