Loss of DC Power on DeFever 53

[oceancrosser]

Hello,

I posted this on the DeFever Forum, however I would like to add this to the Trawler Brain Trust for more visibility.

Hello,

I was very happy with my Crown 6 volt batteries (8 of them) that supported our house bank for the last 5 years, but before we start our summer season I decided to replace them with 8 Trojan 105s (6 volts).

Before starting the removal process, I took copious notes (drawings) and many pictures. Since I had done this very thing 5 years ago, I thought this should be a "no brainer". Last night and while all the batteries were out of the boat, I commented to my wife about the DC powered lights in the boat (salon, stateroom, etc). They were all powered. Hmmm, how does it know?

So obviously they are powered thru some type of converter from our shore power (AC to DC). But the question I have is how? Where? Is there a selector? I know the Inverter will change DC power to AC power, but what changes AC power to DC power?

As Paul Harvey would say.. now the rest of the story.

The next day (today) I started to hook up the wiring to my house bank while meticulously following the drawings and the pictures. Every thing was great... until I attempted to connect the PORT to PANEL cable to the positive lug. Small spark occurred and then all the DC power users stopped working.

Dang... I now have ZERO DC powered users. No lights, no radio, no engine start, and worst of all no power to the head.

Is there a hidden fuse or C/B? Have I done critical damage to my boat. Am I a total dumbass? Okay... Ron... don't answer that one.

Suggestions on where to look?

Thanks,

Rusty
M/V Kristine
DeFever 53 POC
Iuka, MS

 

[Altair38]

It seems that you have a battery charger (converts AC to DC) running off AC shore power aboard your boat. Most but not all battery charges need a battery to work properly, but not all. This could supply 12 Volt power with the batteries removed. When you went to connect the new batteries to the panel, the new batteries were probably partially discharged and combined with the loose connection, it overloaded your battery charger or blew a fuse/circuit breaker. Try turning your battery charger off for a few seconds and then back on. If that doesn't fix the problem, you will need to look for a DC disconnect fuse or circuit breaker.

 

[socalrider]

Do you have separate start batteries? Any sort of combiner switch (1 - 2 - both - off)? Battery charger is a good path to follow as well.

Almost certainly this is not a big problem, you've most likely blown a breaker or a fuse. It's a good opportunity to learn more about your DC system. Do you have a multimeter? If not, get one & start figuring out what's what.

 

[oceancrosser]

It seems that you have a battery charger (converts AC to DC) running off AC shore power aboard your boat. Most but not all battery charges need a battery to work properly, but not all. This could supply 12 Volt power with the batteries removed. When you went to connect the new batteries to the panel, the new batteries were probably partially discharged and combined with the loose connection, it overloaded your battery charger or blew a fuse/circuit breaker. Try turning your battery charger off for a few seconds and then back on. If that doesn't fix the problem, you will need to look for a DC disconnect fuse or circuit breaker.

I have two battery chargers and the first one goes through the Outback Inverter and another in the engine room. Embarrassingly I am not sure which one goes to which system.

I have a separate start bank and house bank that cannot be connected. Two 4Ds supply my start for both generators and engines. 8 Trojan 6 volt supply my house bank.

I am sure the batteries were low on charge since it has been about 3 weeks sitting on the boat. There may have been a big load asked of the BC

This is my second DeFever and I truly love these boats.. but what I hate about these boats is everyone is a "custom build". The wiring diagram is a basic generic layout but as time goes by, owners will add the latest and greatest. And for the life of me... why o' why don't the sparky's that install the latest and greatest remove the old wiring. Behind my electrical panel it looks like a rats nest... disconnected wiring, cut wiring... For pete sake... remove what is not in use. Okay.... sorry... rant.. over! (can you tell this electrical thing has got me frustrated)

Thanks for the suggestions..

Rusty

 

[oceancrosser]

Do you have separate start batteries? Any sort of combiner switch (1 - 2 - both - off)? Battery charger is a good path to follow as well.

Almost certainly this is not a big problem, you've most likely blown a breaker or a fuse. It's a good opportunity to learn more about your DC system. Do you have a multimeter? If not, get one & start figuring out what's what.

As I mentioned in an earlier reply.. I have a two battery system and no combiner switch.

In my book... and certainly with my limited knowledge of all things electrical, this is a BIG deal. I will be reaching out to the shop foreman tomorrow morning and see if they have some suggestions. But.. you are correct, either way I will LEARN more about my DC system.

I do have a multi-meter and understand the basics of it.

Thank you for replying.

Rusty

 

[socalrider]

\This is my second DeFever and I truly love these boats.. but what I hate about these boats is everyone is a "custom build". The wiring diagram is a basic generic layout but as time goes by, owners will add the latest and greatest. And for the life of me... why o' why don't the sparky's that install the latest and greatest remove the old wiring. Behind my electrical panel it looks like a rats nest... disconnected wiring, cut wiring... For pete sake... remove what is not in use. Okay.... sorry... rant.. over! (can you tell this electrical thing has got me frustrated)

As a MechE I feel your pain... I spent a good amount of time pulling old unused wire on our old trawler. I love those 53's and am continuing to look hard at a 51 POC myself actually.

I'd start at the sources - battery chargers, house banks, and start banks. Figuring out where current was coming from when the house bank was removed is step #1. It's either one of the chargers, or there's a connection you're not aware of between the start bank and the house bank. Each of these hypotheses can be tested with your multimeter. Then you can work your way out to the panel, fuses, etc. etc. It's often helpful to have a few lengths of wire with alligator clips (insulated if not ground) so you can extend the reach of your multimeter. Hiring a good technician who can talk you through what they're doing can save days and days of "learning the hard way".

 

[SteveK]

You mentioned an inverter & charger. They or one device was connected to the 8-6V batteries in order to charge them and also to make AC from DC. At the same time those same positive and negative are connected to the house load. There is/was 12V coming out of the inverter or charger powering your lights without any batteries. The spark may have blown a breaker/fuse.

 

[oceancrosser]

As a MechE I feel your pain... I spent a good amount of time pulling old unused wire on our old trawler. I love those 53's and am continuing to look hard at a 51 POC myself actually.

I'd start at the sources - battery chargers, house banks, and start banks. Figuring out where current was coming from when the house bank was removed is step #1. It's either one of the chargers, or there's a connection you're not aware of between the start bank and the house bank. Each of these hypotheses can be tested with your multimeter. Then you can work your way out to the panel, fuses, etc. etc. It's often helpful to have a few lengths of wire with alligator clips (insulated if not ground) so you can extend the reach of your multimeter. Hiring a good technician who can talk you through what they're doing can save days and days of "learning the hard way".

I do a lot of supervised work on my airplane and when I cause an issue, I try to return to the scene of the crime. Your advice on start at the sources is where I am beginning today. I am certainly not a guru on the multi-meter however I think I can manage to find what is powered and what is not.

Thank you so much for responding to my plea.

Rusty

 

[oceancrosser]

You mentioned an inverter & charger. They or one device was connected to the 8-6V batteries in order to charge them and also to make AC from DC. At the same time those same positive and negative are connected to the house load. There is/was 12V coming out of the inverter or charger powering your lights without any batteries. The spark may have blown a breaker/fuse.

SteveK,

A light bulb just went off in my pea brain sized head. My inverter is a charger thus must convert AC to DC thus maintaining the batteries. This is why we had DC lights illuminated while the batteries where out of the boat.

Now if I can find that pesky fuse....

Thanks again for your help.

Rusty

 

[twistedtree]

I agree that it would seema fuse blew somewhere when you connected the batteries, but it shouldn't have. So I think you have two problems. First is to find and replace the fuse (or reset the breaker), and the second is to figure out what's wrong with your wiring that caused the trip in the first place.

With your meter, and the final battery wire connection still not made to the rest of the boat, check the voltage from the boat's negative system to the battery bank's positive terminal (the terminal you plan to connect to the boat's positive power loads). Confirm that it's +12V, paying equal attention to the voltage and the polarity.

Once you have verified that you bank is correctly wired and have located and replaced whatever fuse blew, turn off your chargers, including the inverter and other DC loads like lights, etc. Then make the final battery connection. Then turn a few things on to confirm that it works.

 

[SteveK]

some inverters have a pop out breaker on the body of the inverter

 

[Portage_Bay]

A little late, but in the for what it's worth column when I replace battery banks here is what I do.

Diagram the system as you did. Pictures, lots of pictures. Lots of labels, painter's tape and a sharpie work fine. Then power everything down. All DC loads, all DC sources, chargers, inverter/chargers, power supplies, solar. Everything. One AC circuit live in the engine room, or wherever your bank is, and work from drop lights and head lamps. Yeah it's a PITA. But when it's years since I did the last bank change out I want to be extra careful. Far worse things can happen than a blown fuse or popped breaker.

 

[oceancrosser]

A little late, but in the for what it's worth column when I replace battery banks here is what I do.

Diagram the system as you did. Pictures, lots of pictures. Lots of labels, painter's tape and a sharpie work fine. Then power everything down. All DC loads, all DC sources, chargers, inverter/chargers, power supplies, solar. Everything. One AC circuit live in the engine room, or wherever your bank is, and work from drop lights and head lamps. Yeah it's a PITA. But when it's years since I did the last bank change out I want to be extra careful. Far worse things can happen than a blown fuse or popped breaker.

Never too late... but I did follow "most" of your directions. Copious notes.. diagrams (stick figures) and lots of pictures. I did realize I am NOT a photographer!

 

[Portage_Bay]

I did realize I am NOT a photographer!

Nor I. I take tons of pics from lots of angles. Yet when I go to put something back together I wish I'd taken more.

 

[Bmarler]

There’s enough power in the house bank to do some pretty serious welding. Be careful with it. I have a disconnect between the batteries and the positive buss so I can isolate the house bank easily. I make all the battery connections with the disconnect off, check the bank voltage before energizing the circuit.

 

[oceancrosser]

Folks,

I am perplexed... but not as perplexed as I was dealing with my battery issues.

I am truly grateful for all the replies, suggestions and instructions and it was my understanding my reply to the group had been posted however after spending some time on the computer this evening, I can't find what I had posted. Go figure.

Here is what I discovered.

As I was rethinking, replaying and redoing my previous days installation, I decided to start from the beginning and use my multi-meter after each step.

This is where I discovered my rookie mistake.

During my buildup in making the battery bank a 12 volt system, I mistakenly connected a POS to a POS. We all know that won't work and when I connected my inverter, it went off line thus shutting down my battery charger. This shut down all my DC powered users.

Once I had all the cabling in place and reconnected to the inverter, everything returned to normal. Lucky me... no damage, just the damage to my ego.

Thanks again to all that helped me.

rusty

 

[socalrider]

Congrats on figuring it out, and bonus points for no harm done! Great that you were able to figure it out on your own as well - will give greater confidence the next time something mysterious happens.

I had lots of mysterious things happen for the first six months or so I owned my boat. Now nothing that happens is mysterious as I've re-wired the whole thing pretty much!

 

[oceancrosser]

I had lots of mysterious things happen for the first six months or so I owned my boat. Now nothing that happens is mysterious as I've re-wired the whole thing pretty much!

Thanks for the reply.. but the odd thing is I have owned this boat almost 10 years and I am still learning things each time we cruise. I guess that is a good thing.

Travel safe,

Rusty