Decision Time - House Bank Is Toast

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I'd still do the 20 hour load test, even with what's been mentioned here. Under a decent load, 11.6 volts is a very high cut-off threshold. Knowing they hit that while drawn down about 15% makes me think they may be weak, but it's hard to say for sure.
 
I'd still do the 20 hour load test, even with what's been mentioned here. Under a decent load, 11.6 volts is a very high cut-off threshold. Knowing they hit that while drawn down about 15% makes me think they may be weak, but it's hard to say for sure.

i think he said that 10.5 was the cut off set point. 11.6 is what he measured after he noticed the cutoff. there must have been some rebound. we can't know what they might settle at after 24 hours, but it would be interesting if that became known.
 
Will try to isolate the loads better today. I agree 48a is too much for what I think I have running.

Also looking at a battery load tester - such as the Foxwell BT705 which is reasonably priced (not affiliated just interested customer).

Are these worth the cost of admission to your tool box?
 

I agree that running the ER blowers when not underway is unusual, to say the least. I could see running them for a bit after shut down to cool the ER off a bit, but after that I don't see any need to run them, and I'll bet they are 1/3 or more of your load. But maybe there is some special need?



Now this is really independent of whether your batteries are toast or not, and whether you replace with lead or LFP. But any choice going forward will benefit from reducing unnecessary loads.
 
Will try to isolate the loads better today. I agree 48a is too much for what I think I have running.

Also looking at a battery load tester - such as the Foxwell BT705 which is reasonably priced (not affiliated just interested customer).

Are these worth the cost of admission to your tool box?


Testers like that will work fine for starting batteries, but they don't really tell you much about condition of a big deep cycle bank. A full discharge test tells far more.
 
...I agree that running the ER blowers when not underway is unusual, to say the least. I could see running them for a bit after shut down to cool the ER ...


Running only to cool the engine room. Not continuously.
 
Mark
Do you have a good BMK monitoring your house bank? By turning various 110volt loads on and off you can assess instantly the change in amps and volts. Load assessment management without a modern properly set up BMK is difficult at best.

Possibly more information would assist you in making your go forward battery decisions. BTW, a decade ago I got rid of our Xantrex inverter charger and Link system and installed a Magnum BMK. What an improvement.

There are other monitoring systems that are specific for the inverter brand and work quite well too.
 
[FONT=&quot]WATCH:
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A state-owned public transport operator in Paris, France, the Régie Autonome des Transports Parisiens, has pulled out 149 electric buses from its fleet after two of them spontaneously exploded within the same month.
The RATP decided to temporarily retire the electric vehicles after the second explosion occurred around 9 a.m. on April 29 near the François Mitterrand Library, according to reporting from the local newspaper Le Parisien and a RATP news release.
Footage of the bus engulfed in flames in Paris’s 13th arrondissement was widely circulated on social media.
A video by VIXX compiling the viral videos showed smoke emanating from the top of the bus, where the battery is located. The smoke gave way to an explosion and a shower of sparks that covered the vehicle’s mid-section and nearby areas.
[FONT=&quot]
https://www.youtube.com/watch?v=5r-yN8SugWM[/FONT]
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Flames eventually engulfed the electric vehicle, and the ravaging inferno gave rise to tall columns of thick black smoke visible from surrounding areas, the video showed. The air was filled with the smell of burning plastic.
Fortunately, there were no casualties due to the fire. The bus driver was able to get out, the arrondissement’s mayor Jérôme Coumet confirmed.
Firefighters promptly responded to the incident. Authorities closed the nearby metro station from 9 am to 11 am to help them put out the blazing inferno, Le Figaro reported.
The bus that was engulfed in flames on April 29 and the one that caught fire earlier that month both belonged to the Bluebus 5SE series of the brand Bolloré, according to the RATP.
The RATP has requested the manufacturer to carry out a full investigation to explain the causes of the fire and provide the RATP with an action plan to bring the electric buses safely back into operation.
The two fires in Paris and similar incidents worldwide have raised concerns about the safety of electric vehicles amid a push toward making them replace those running on fossil fuels by activists and lawmakers.
The government of India last month urged electric motorcycle companies operating in the country to carry out voluntary recalls of their products.
The country’s authorities did so to ensure electric motorcycles were safe for consumers after a series of electric scooters caught fire in the country, the Indian newspaper The Hindu reported.
“Lithium has a natural affinity for fires,’’ Amit Das, the founder of the Indian multi-brand electric vehicle store chain Electric One, said, according to the Business Standard. Lithium is a common element in electric vehicle batteries.
Besides safety concerns, electric vehicles face other sets of problems, such as governments adding new taxes to compensate for revenue losses that came with incentives given to motorists for switching from gas/diesel-powered vehicles to electric ones.
On top of that are ethical concerns that arise due to the nature of the process of mining raw materials to make electric vehicles and the emissions involved therein & their disposal.
 
Mark
Do you have a good BMK monitoring your house bank? By turning various 110volt loads on and off you can assess instantly the change in amps and volts. Load assessment management without a modern properly set up BMK is difficult at best.

Possibly more information would assist you in making your go forward battery decisions. BTW, a decade ago I got rid of our Xantrex inverter charger and Link system and installed a Magnum BMK. What an improvement.

There are other monitoring systems that are specific for the inverter brand and work quite well too.


In addition to the Xantrex monitoring system I also have a Victron battery monitor that shows current draw, Amps consumed, state of charge etc.
 
In addition to the Xantrex monitoring system I also have a Victron battery monitor that shows current draw, Amps consumed, state of charge etc.

My bad for not reading your first post on this issue carefully enough. What is output of the Xantrex and any other chargers you have onboard?
 
On top of that are ethical concerns that arise due to the nature of the process of mining raw materials to make electric vehicles and the emissions involved therein & their disposal.

So where else do we get raw materials if we don't mine them?
 
Lots of advice here, some good and some, well...

My first test would be a quick check of voltage under discharge at the batteries and at the inverter. What you are doing is simply verifying that there is not a voltage drop occurring.

If that is the case then yes your house bank is probably at end of life.

At a 50% discharge your lead acid battery bank under load should still be at around 11.6 volts which will not shut down any inverter or cause any problems. In face my battery bank was at 50% this morning and was at 11.6 volts.

Further the idea that you need a larger battery bank is just not true, if you are OK with running your generator when you get up in the morning. I for one need to run the generator to make water, cook, make coffee, etc... so I have no problem having a battery bank sized to my needs, and my cruising style, not what someone else deems the "correct size"

Should you spend the money on Lithium? That is a question only you can answer. My opinion is that if your charging system is not capable of exceeding the charge rate of your Lead Acid bank then there is not much to gain by switching to Lithium. So now we are not just looking at battery replacement, wer are looking at a wholesale changeout of your charging system and all that entails.

If ity were my boat I would spend the $1500 or so to change out the LA batteries, and pay another $500 for a couple of strong indiciduals to do the heavy lifting while you enjoy a cold beer and remember when you were young and strong.
 
OK but real use of the system did essentially this test. I drew a bit less than the 20% amperage (48a) for 3.5 hours and the system cutout on low battery voltage. Isn't that enough to let me know that the battery capacity is not there?

3.5 X 48= 168 and 10.5 tripped, I see another noted that. So what was the SOC at the start? What was voltage after the trip? As pointed out 11.6v is approx. 50% discharge.
IMO, tripping at 10.5v only suggests a large draw, that draw that is keeping a 48a average. the voltage after trip could confirm change the batteries if they do not recover above 11.6~
 
My bad for not reading your first post on this issue carefully enough. What is output of the Xantrex and any other chargers you have onboard?
Xantrex (2) are rated 150a charging
 
Power Audit Completed

I've spent a few hours over the past few days trying to figure out where my power goes. While I'm not shocked at the results, I am surprised at how quickly things add up...

My 48A 'average' discharge rate while anchored out is exactly in line with my findings. Here are the loads I identified:

- 6.5A with all breakers OFF, both inverters ON. (This includes inverter overhead and all the 'sneaker' loads that are not tied to either a 120v or 12v breaker.)
- 9A engine room 12V exhaust blower
- 2A GPS system ON (anchor watch)
- 2A anchor light
- 1A AFT Stairwell LED lights
- 1.4A FWD stairwell LED lights
- 13A galley 120V refrigerator
- 13A engine room LED strip lights
- 5A engine room 120V circ fan
- 5A small refrigerator on FB
- 3A TV / Stereo system
- 2A Salon outlets (phone chargers, etc)

That all adds up to over 66A, take away 13A for the galley fridge cycling and we are right at 48A average draw.

Surprises: I had no idea that my engine room lights draw so much! I have 4 duplex fluorescent fixtures that draw 15A, and the LED strip lights (8) draw 13A by themselves. Guess I'll be going dark while at anchor from now on.

Now that I understand how I can reduce the load, I'm still left with a 1200 Ah house bank that quits after forking out ~165Ah. I guess all that's left is to determine if I have 1 (or more) bad batteries affecting the whole bank.

How do I setup a proper load test to determine if the batteries need replacement? Specifically, what do I use for a load if, as I'm told, the automotive battery testers are not the way to go?
 
Looking at bare minimums, I can likely get my load down to 25A +/- with all blowers & unnecessary lights off. That should be handled easily by a 1200 Ah house bank - assuming it's in decent shape..... Just looking for overnight operation without the generator running.
 
At the price point of Ampere time 300 ah lifepo4 for 1300 ish your getting the equivalent of nearly 600 ah of agm or Fla, at not much more the price.
I've had several Insurance policies on both my own and customers boats and have yet to see proof of insurance having any issues with lifepo4. I have used relion, kilovault and amperetime, with great results
 
You can easily cut the anchor light down too. A good LED unit will draw no more than 0.25 amps, even for something brighter than the minimum requirements.

The fridges also won't be a constant load, they'll cycle on and off.
 
How do I setup a proper load test to determine if the batteries need replacement? Specifically, what do I use for a load if, as I'm told, the automotive battery testers are not the way to go?

One way to do this would be to test the voltage across each battery under load (with the other batteries disconnected).

Not sure how difficult this would be with your pack setup, but the idea would be to run the pack down a bit, then pick a set of known loads (e.g. lights, blowers, no fridges). Run those same loads off each 12V house battery individually without the others connected & note the voltage. Then turn off the loads, switch the the next battery & repeat.

If you have a bad battery, its voltage will likely plummet compared to the others when you turn the load on.

If you find such a battery, you can hook the rest of your house bank back up & leave it out of the loop until you can replace.
 
How many LED lights are you running to draw that much current? My LEDs don’t draw nearly that much. They are in the 30 to 50 mAmps range. So 20 to 30 of them may draw an amp.
 
How many LED lights are you running to draw that much current? My LEDs don’t draw nearly that much. They are in the 30 to 50 mAmps range. So 20 to 30 of them may draw an amp.


Yeah, not sure about that unless you count each individual led in a bulb.

A single 6w @ 12v warm white mr16 led draws 0.5 amp
But it has probably 8 individual leds in it.
 
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It could be just one cell on one of the 8Ds bad. Test the 8Ds individually.

Totally agree. The red flag for me is if your agm's are bad after 4 years. I would not want to purchase new batteries before verifying the batteries are correctly setup-same wire length, positive and negative hooked up on opposite ends of the house bank, etc. One bad battery can take down the whole house bank. I would also verify the correct charging voltage with a meter. As someone already stated, improper charging will kill the batteries.
 
I've spent a few hours over the past few days trying to figure out where my power goes. While I'm not shocked at the results, I am surprised at how quickly things add up...

My 48A 'average' discharge rate while anchored out is exactly in line with my findings. Here are the loads I identified:

- 6.5A with all breakers OFF, both inverters ON. (This includes inverter overhead and all the 'sneaker' loads that are not tied to either a 120v or 12v breaker.)
- 9A engine room 12V exhaust blower
- 2A GPS system ON (anchor watch)
- 2A anchor light
- 1A AFT Stairwell LED lights
- 1.4A FWD stairwell LED lights
- 13A galley 120V refrigerator
- 13A engine room LED strip lights
- 5A engine room 120V circ fan
- 5A small refrigerator on FB
- 3A TV / Stereo system
- 2A Salon outlets (phone chargers, etc)

That all adds up to over 66A, take away 13A for the galley fridge cycling and we are right at 48A average draw.


Something not right there

We run as much if not more than that
No ER lights or fans at night (why would you?) But do have 30 cubic feet of household 240v refrigeration across 4 units going 24/7

On a 24v system the most I have seen on our Victron 712 is around 21 amps but usually around 12 amps
So 42 and 24
 
Your system is 12V, and I think you are dealing with 12V batteries, not 6V? If that’s correct, all the batteries will be in parallel, and as such will always meter out to the same value. To suss out a bad battery, you will need to disconnect them one at a time, and then measure each individually. You only need to disconnect either the positive side or the negative side - it doesn’t matter which. Let us know what voltage readings you get. Maybe there is just one bad battery, or one that’s much worse than the others.
 
How many LED lights are you running to draw that much current? My LEDs don’t draw nearly that much. They are in the 30 to 50 mAmps range. So 20 to 30 of them may draw an amp.


There are 8 shop LED lights 4 feet long so 32 feet of LEDs. They are 120v units.
 
...On a 24v system the most I have seen on our Victron 712 is around 21 amps but usually around 12 amps
So 42 and 24


Not seeing a significant difference here... I'm at 48 and likely 25 when I kill the ER lights / fans at the end of the day. What am I missing?
 
Why are the ER lights on while you're not down there? In my mind, those only need to be on for engine checks or while doing maintenance.
 
Not seeing a significant difference here... I'm at 48 and likely 25 when I kill the ER lights / fans at the end of the day. What am I missing?

The 48 amp average

...

My 48A 'average' discharge rate while anchored out

You are saying now it's 48 peak and 25 low so likely an average around mid 30
 
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Why are the ER lights on while you're not down there? In my mind, those only need to be on for engine checks or while doing maintenance.
Had wrongly assumed that since they were LED that draw would be really low. Lesson learned...
 
I have casually browsed this thread for several days. Really feels like some sort of energy audit/budget would help you make informed choices and decisions. A bit daunting on a 62-foot boat but if you seek a quiet existance, its something you need to do (even if just rough-estimates). When I did it, I was surprised at the little stuff - PCs, TVs, etc. They do indeed add-up.

There are two XLS attachments in this URL for ocean-racers in the Pacific Cup. Although geared towards smaller, simpler boats, the format is easily expanded.

https://pacificcup.org/kb/energy-management

Good luck -

Peter
 

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