Emails from the boat

[ksanders]

Today was like almost any other day. I did my thing while my boat sat all alone at the marina. Then I received this email message

From:
MV LISAS WAY ALARM SYSTEM

Alarm detected on Zone 1: SHORE POWER
Alarm occurred on Monday, February 16, 2015 at 1:43:57pm It is now C: OUTAGE

Then a few minutes I received this email

From:
MV LISAS WAY ALARM SYSTEM

Low Alarm detected on Zone 3: DC BATTERY Alarm occurred on Monday, February 16, 2015 at 1:48:01pm It is now 11.94VOLTS Level crossed limit of 12.00VOLTS

Then this email

From:
MV LISAS WAY ALARM SYSTEM

Return to Normal detected on Zone 3: DC BATTERY Alarm occurred on Monday, February 16, 2015 at 2:03:37pm It is now 12.03VOLTS

Then this email

From:
MV LISAS WAY ALARM SYSTEM

Low Alarm detected on Zone 3: DC BATTERY Alarm occurred on Monday, February 16, 2015 at 2:46:37pm It is now 11.98VOLTS Level crossed limit of 12.00VOLTS

Then I got several more emails as my battery voltage fluctuated between 11.95 and 12.03 bolts and finally...

From:
MV LISAS WAY ALARM SYSTEM

Return to Normal detected on Zone 3: DC BATTERY Alarm occurred on Monday, February 16, 2015 at 3:39:30pm It is now 13.36VOLTS


And this one

From:
MV LISAS WAY ALARM SYSTEM

Return to Normal detected on Zone 1: SHORE POWER Alarm occurred on Monday, February 16, 2015 at 3:40:16pm It is now O: NORMAL

So, we leave our boats for days, sometimes weeks at a time.

Do we really know whats going on aboard our boat? Do we know the battery charger has not failed causing our batteries to drain and our bilge pumps not to work?

What do we really know about our boats while we are away?

 

[tpbrady]

Kevin,

Can you give me the ABC's of what you have on board that does this?

Thanks.

Tom

 

[ksanders]

Kevin,

Can you give me the ABC's of what you have on board that does this?

Thanks.

Tom

The alarm system is a Sensaphone brand model WEB600

The shore power sensing is a simple 120 volt relay tied to the web600

The DC battery is a OMEGA 0-15 volt to 4-20MA converter.

The sensaphone ties to the boats network which is just a AT&T usb modem tied to a Cradlepoint MBR1200 router

 

[tpbrady]

Thanks Kevin,

Doesn't look too difficult. Did you connect any temp sensors or bilge pump counters?

Tom

 

[ksanders]

Thanks Kevin,

Doesn't look too difficult. Did you connect any temp sensors or bilge pump counters?

Tom

Yes I have two separate high bilge water float switches, plus cabin temp and engine room temp.

 

[twistedtree]

That seems like a very fast battery voltage drop after loss of shore power. Why would that be, or an I miss-reading the messages?

 

[ksanders]

That seems like a very fast battery voltage drop after loss of shore power. Why would that be, or an I miss-reading the messages?

No, the readings are correct.

Thats not bad at all. My boat draws on average around 25 amps DC to run the stuff on the boat. The satellite communications system is a big user, plus I have two diesel furnaces on.

You're probably aware of this but lead acid storage batteries will start out at float voltage, then drop below nominal voltage, then rebound to almost exactly their nominal voltage for much of their useful capacity. The drop and rebound typically ocures in the first 15 minutes.

This is a phenomonon I did not believe when it was taught in my battery schools but I saw first hand zillions of times when testing battery banks for telecom applications.

That is exactly waht the readings indicate. Four minutes after power loss the voltage was 11.94 but by 18 minutes after power loss the voltage had restored to 12.0 volts and stayed their +- throughout the outage.

The nominal voltage tables we floating arounf TF are based on a no load condition and are very misleading since almost any large boat has a load on the batteries all the time.

 

[twistedtree]

Interesting. I've actually never experienced that. I've always seen them slowly work their way down, but maybe that's related to the load as a % of bank capacity? How many Ah of battery capacity do you have?

 

[ksanders]

Interesting. I've actually never experienced that. I've always seen them slowly work their way down, but maybe that's related to the load as a % of bank capacity? How many Ah of battery capacity do you have?

Could be, these are 850 amp hour

It is allot more pronounced when testing basically the same technology in a telecom application. A typical bank would be 2500 amp hours at 48 volts. testing was done with a 100 amp minimum load.

 

[ksanders]

BTW...

What is the battery and charging capacity of that monster boat of yours?

 

[twistedtree]

I replied earlier, but fat-fingered it somehow.....

I think the lower draw is where the difference lies. My at-anchor load is 11-25A depending on what's running, pulling from 1000ah of batteries. My house (I have an off-grid house which is basically a boat that's run aground) has an even lower load on 1300ah @48V. 300-700watts is a typical load.

To your last question, the Nordy battery bank isn't that huge @ 1000 ah. Not small, but not huge either. Over the years I've learned that keeping the load down is where the max benefit is derived.

 

[ksanders]

I replied earlier, but fat-fingered it somehow.....

I think the lower draw is where the difference lies. My at-anchor load is 11-25A depending on what's running, pulling from 1000ah of batteries. My house (I have an off-grid house which is basically a boat that's run aground) has an even lower load on 1300ah @48V. 300-700watts is a typical load.

To your last question, the Nordy battery bank isn't that huge @ 1000 ah. Not small, but not huge either. Over the years I've learned that keeping the load down is where the max benefit is derived.

That is very cool!

I like the off grid house.

We have power at our house but run a dual generator back up system.

The folks you meet, very cool!

 

[Marin]

What do we really know about our boats while we are away?

Good question. We don't have an alarm system on our PNW boat, which is berthed 100 miles north of our house. But all the docks in the harbor are regularly patrolled by the port's security folks and the gates to the main docks are locked (in theory) after sundown. There are also cameras on each dock which are monitored (in theory) in the port's security office.

We also have some liveaboards on our dock which makes for a great watch/alarm system. Our and the port's phone numbers are on a laminated sheet we keep in a dockside window.

Other than that we just take it on faith that the boat is surviving on top of the water. So far it's done okay for the last 16 years.

We worry most about the storms that come blasting through in series during the winter with wind gusts to 60-80 mph in our harbor. Some of our canvas was old when we bought the boat and only my wife's diligence with a sewing machine and real good thread have kept the older pieces alive. We always wonder how it's doing when we look on our iPads at the current wind speeds as measured by the weather station on top of Bellingham Cold Storage's ice house across from our boat.

 

[ksanders]

One time I went to the boat only to find that the shore power breaker at the dock side was off.

I do not know how it turned off or when. I do not know if it tripped, or if someone across from us on the transient dock borrowed our shore power and forgot to turn it back on.

I had fish and bait, and meat in the freezer, and it was summer. The food in the freezer was ruined but not yet smelly.

My batteries were flat. Of course my bilge pumps were offline.

Fortunately my batteries took a charge and all was good after cleaning up the mess in the freezer.

I decided that my whole boat could have been at risk for a simple shore power connection.

So I decided not to let that happen again.

 

[twistedtree]

One time I went to the boat only to find that the shore power breaker at the dock side was off.

I do not know how it turned off or when. I do not know if it tripped, or if someone across from us on the transient dock borrowed our shore power and forgot to turn it back on.

I had fish and bait, and meat in the freezer, and it was summer. The food in the freezer was ruined but not yet smelly.

My batteries were flat. Of course my bilge pumps were offline.

Fortunately my batteries took a charge and all was good after cleaning up the mess in the freezer.

I decided that my whole boat could have been at risk for a simple shore power connection.

So I decided not to let that happen again.

That's what I worry about. We leave the fridge and a few things on when we are away. A prolonged shore power loss will make a mess of the fridge and its contents, and potentially inflict lasting damage on the batteries. Not to mention the loss of bilge pumping and alarming capability.

Local power outages are one source, but I think the more probably threat is as you describe. Someone inadvertently turns off your breaker, trips a breaker, moves your power cord, or whatever. With an alarm or two you have a fighting chance of dealing with the problem before it gets ugly.

 

[windmill29130]

One major reason we have insurance!

 

[ksanders]

One major reason we have insurance!

I don't look at it that way. If I can reasonably prevent a loss I think its my duty to do so.

I'm not saying everybody should be required to have an alarm system. What I'm saying is that we should take proactive measures to reduce our risk. Those measures might be a high bilge water alarm with a light or siren. They might be knowing someone is regularly checking on the boat. But my insurance is not my proactive measure, it is a last ditch means of making me whole, should all else fail.

With today's technology I am happy that I have the ability to know whats going on with my boat 24X7X365.

As far as the insurance, well you might approach your marine insurance carrier and discuss lowering your risk and the potential lowering of your insurance rate to match that lowered risk. You might be surprised at the response.

 

[twistedtree]

One major reason we have insurance!

I don't know about you, but I have a pretty high deductible on my insurance. Interesting question too whether it would cover lost food or ruined batteries. But probably moot since I doubt it would be more than the deductible.

 

[BandB]

I am a worrier. I would be worrying constantly if I didn't have an alarm system for bilge water, batteries and even, yes, security. I never question my investment in them as state of mind is critical for me to enjoy. Now typically if there was an issue I can have someone where the boat is at that time walk and check. We even have the alarms set when we're going to town or just to dinner. And while one says insurance, I'd have to have a sizable claim (boat sinking would qualify but loss of food wouldn't) before I'm going to go to my insurance. The potential impact to rates discourages me. Now, while one small claim isn't going to impact you, the risk is that it's followed by a larger claim you must file. Now, suddenly, they see a history of claims. Boat insurers don't really need a lot of excuses to say no anyway. Many are only looking for the perfect situation in who they insure.

 

[kulas44]

I leave my boat for sometimes extended periods also, and I do worry about stuff, mostly the water "stuff" staying on the outside. Anything else I can handle. I have a freezer and 2 fridges aboard. 2 inverters for redundancy, but I NEVER leave them in invert mode when I'm not there. My reasoning is that the freezer/fridges would deplete the batt bank in just a few days. And, the solar cant keep up. Without that load the batts could last for weeks or months depending on bilge pump usage, which is very little. I can deal with rotted food just not wet food. The cell based monitoring system is high on my list of needs.

 

[Phil Fill]

What its telling you is the AC eletrical was out for 2 hours and the battery charger charges at 13.32 volts. However the batteries not being charged is around 12.0 volts, and the batteries may need replacing.

Old school a full charged battery was 13.0 volts, 12.8 volts was 75% charged, 12.4 volts was 50% charged below 12.2 volts they need to be checked and probable replaced. At 12.4 volts batteries should be charged.

 

[ksanders]

What its telling you is the AC eletrical was out for 2 hours and the battery charger charges at 13.32 volts. However the batteries not being charged is around 12.0 volts, and the batteries may need replacing.

Old school a full charged battery was 13.0 volts, 12.8 volts was 75% charged, 12.4 volts was 50% charged below 12.2 volts they need to be checked and probable replaced. At 12.4 volts batteries should be charged.

Sorry but that data is absolutely incorrect.

There is nothing wrong with my battery bank. But thanks for the concern.

 

[alormaria]

The secret lives of boats...... REVEALED!