Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 28-07-2020, 13:04   #16
Registered User
 
APWTryfan's Avatar

Join Date: Sep 2018
Posts: 44
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by Statistical View Post
From the photos and description you had an uncontrolled flow from DC+ to ground between the battery switch and charger. The two most likely scenarios are a short developed in the wiring or the shore charger failed internally. Of the two I think the wiring is more likely. Years (decade?) of the wiring moving and rubbing against the clamps could eventually wear through the insulation.

A fuse on the DC+ wire going to the charger would have protected your wiring in both scenarios. Your first indication of a problem would be no charging when you connected to shore power. I am not saying that to attack you just something to consider when you rebuild after this incident. Glad your family is ok.
Thank you. We've shore charged without issue during the winters for the 2 years we've had the boat. This year we have not been plugged in since beginning of summer as the solar was connected and kept the batteries maintained.
__________________

APWTryfan is offline   Reply With Quote
Old 28-07-2020, 13:09   #17
Registered User
 
APWTryfan's Avatar

Join Date: Sep 2018
Posts: 44
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by Lake-Effect View Post
Agree with others that solar was not a factor. I haven't looked at the pix, but from the description it seems pretty clear that there was a short on the charger wires. Please report back as to whether it was the charger, or a physical short somewhere.

Anyway the fix (... besides replacing everything that burned) is to fuse the positive wire of the charger up close to the 1/2/both/off switch. This fuse's job is to protect the charger wiring from the massive currents possible from the batteries if there's ever a short on the charger wires.

(Bah, that'll never happen, right? )
Thank you for sure I will report back if I can determine the cause.

I'm no forensic specialist by any stretch, and still have all the charred cut up wires and the shore charger. I think it would be difficult to identify cause of potential wire short, and will have a closer look - and will also need to look at the shore charger. If there was a short in the wire that caused that much damage I would think it would have also fried the shore charger.

When I install shore charger later I will for sure had fuse as you had suggested thanks.
__________________

APWTryfan is offline   Reply With Quote
Old 28-07-2020, 13:16   #18
Registered User
 
APWTryfan's Avatar

Join Date: Sep 2018
Posts: 44
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by Frankly View Post
In a previous life I did two similar insurance boat fire investigation. Both were caused by battery chargers that were connected directly to battery systems. The battery chargers had cicuit protection on the charger end but nothing on the battery end. Shorts occured in the connecting wiring and the 30 amp charger wiring was exposed to hundred of amps flowing back from the batteries.

The normal tunnel thinking is circuit protection at the current source (battery charger). Works fine until a short develops in the wiring an now the source is the batteries. Charging needs to be fused on both ends. Solar not the same as it is current limited on the controller end.

One system was factory installed one owner installed.

Frankly
Interesting thanks...

The shore charger was connected to B1 and B2 poles on switch and not fused I will fuse both when I replace. The alternator is connected to common pole on switch not sure if there is a fuse on that wire - I think not. The solar connected to B2 house and appropriately fused.

Given that we were not plugged in and running under motor it would seem that future shore charger should be fused at both ends.
APWTryfan is offline   Reply With Quote
Old 28-07-2020, 13:18   #19
Registered User
 
APWTryfan's Avatar

Join Date: Sep 2018
Posts: 44
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by stormalong View Post
That is a lot of damage. Probably a wiring short. You have so much secondary damage that every wire that shows any damage should be removed or at least disconnected before using anything on the boat. If that makes your essential systems inoperable fix them before continuing on your vacation.

That might sound harsh but you and your family's safety is at stake. A repeat fire could be a killer. Once fiberglass starts burning it is almost impossible to put it out.
That is absolutely 100% the plan - I've already mostly assessed the damage - along with getting a professional opinion. Thanks.
APWTryfan is offline   Reply With Quote
Old 28-07-2020, 13:38   #20
Registered User
 
APWTryfan's Avatar

Join Date: Sep 2018
Posts: 44
Re: Electrical Fire - Seeking Help Please

Thanks all for your helpful responses thus far.

One last thing click here for a picture of the charger.

The only damage appears to be at the wire connections.
APWTryfan is offline   Reply With Quote
Old 28-07-2020, 13:40   #21
Registered User
 
Jammer's Avatar

Join Date: Jan 2010
Posts: 1,502
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by APWTryfan View Post
I am hoping for meaningful responses that can help me understand what happened and hopefully help others too.

I am truly sorry for the unfortunate turn of events and am grateful that you posted here with detail so that others can learn.

I have seen equipment fires involving a shorted battery connection like that and they are, just as you describe, very fast and very frightening.

Like several commenters upthread, I believe that there was a short circuit in or very, very near to the shore charger. It is possible that careful examination and disassembly of the charger may provide more detail, for example, you may find that a piece of hardware came loose and fell onto current-carrying components. Or you may find evidence that the wire terminals came into contact with each other where they connect to the charger. Either way, I think it is unlikely that any other components on the boat played any sort of role in the sequence of events.

I would not expect to find other damage to your electrical system, beyond those wires and cables obviously damaged by their proximity to the wires that burned.


Looking at your wiring diagram, it appears to me that there is insufficient circuit protection overall. A number of approaches for remediation is posisble. ABYC standards would have varying requirements depending on the length of some of the cable runs and whether they are in conduit.


In general, however, there should be some sort of overcurrent protection in these places:


1) In the + connection to the start battery, as close to the battery as possible, so that current to both the ACR and the OFF-1-2-BOTH switch goes through the overcurrent protection.



2) In the + connection from the house bank to the OFF-1-2-BOTH switch, as close to the battery as possible.


3) In the + connection from the house bank to the ACR, unless the cable can be relocated to share the overcurrent connection for the OFF-1-2-BOTH switch.


4) In the + connection from the house bank to the solar controller


5) In each of the two + connections from the OFF-1-2-BOTH switch to the battery charger. If your replacement charger only has one battery connection, then you can remove the extra cable and won't need overcurrent protection for it.


6) While not required, I would consider overcurrent protection between the OFF-1-2-BOTH switch and the panel, especially if the run is long or is made of lighter gauge wire.


These will be expensive changes and take time. You may want to survey your overall electrical system as there are some practices which, while not necessarily unsafe, may not be the best recommended practices.
Jammer is online now   Reply With Quote
Old 28-07-2020, 14:06   #22
Registered User

Join Date: May 2011
Location: Lake Ont
Posts: 5,572
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by APWTryfan View Post
I'm no forensic specialist by any stretch, and still have all the charred cut up wires and the shore charger. I think it would be difficult to identify cause of potential wire short, and will have a closer look - and will also need to look at the shore charger. If there was a short in the wire that caused that much damage I would think it would have also fried the shore charger.
So I finally looked at your excellent pix. The fact that right at the charger it was the charger's black wire that melted, not the red, suggests to me that there's no short - and possibly nothing wrong - in the charger. (Take the charger out and try it on some other batteries) So, I would follow the melted red wire from the battery switch; I think you'll find that somewhere it gets shorted to the charger black wire.

If that red wire was fused right near the battery switch, it would have blown and there would not have been a fire.

(and thanks very much for sharing your story. It will help many people)
Lake-Effect is offline   Reply With Quote
Old 28-07-2020, 14:45   #23
Registered User

Join Date: Jun 2008
Posts: 297
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by Lake-Effect View Post
So I finally looked at your excellent pix. The fact that right at the charger it was the charger's black wire that melted, not the red, suggests to me that there's no short - and possibly nothing wrong - in the charger. (Take the charger out and try it on some other batteries) So, I would follow the melted red wire from the battery switch; I think you'll find that somewhere it gets shorted to the charger black wire.

If that red wire was fused right near the battery switch, it would have blown and there would not have been a fire.

(and thanks very much for sharing your story. It will help many people)

Look at that picture again. The positive wire has burned through the red insulation (which is all that is connected to the charger) and has fallen down the left side of the picture. The insulation has melted off the black wire all the way up to the charger. The charger definitely had an internal short.

That red wire break is likely what saved the boat.
JayH is offline   Reply With Quote
Old 28-07-2020, 14:55   #24
Registered User
 
BlackHeron's Avatar

Join Date: Jan 2016
Location: Summering on the Chesapeake
Boat: Hallberg-Rassy Rasmus 35
Posts: 717
Images: 19
Re: Electrical Fire - Seeking Help Please

Fusing, fusing, fusing. If there is a short, and wire starts on fire, then there should have been a fuse somewhere protecting it.
BlackHeron is offline   Reply With Quote
Old 28-07-2020, 15:06   #25
Registered User
 
APWTryfan's Avatar

Join Date: Sep 2018
Posts: 44
Re: Electrical Fire - Seeking Help Please

Yes indeed thank you!
Quote:
Originally Posted by BlackHeron View Post
Fusing, fusing, fusing. If there is a short, and wire starts on fire, then there should have been a fuse somewhere protecting it.
APWTryfan is offline   Reply With Quote
Old 28-07-2020, 15:08   #26
Registered User

Join Date: May 2011
Location: Lake Ont
Posts: 5,572
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by JayH View Post
Look at that picture again. The positive wire has burned through the red insulation (which is all that is connected to the charger) and has fallen down the left side of the picture. The insulation has melted off the black wire all the way up to the charger. The charger definitely had an internal short.
First, I see that the OP included a picture of the opened charger, which I missed before. So... I see the ground trace got pretty hot as well. One would need to determine whether any of that ground path is compromised because of the heating, or if there was heating-caused damage to other components. Insurance would probably say it's not worth fixing and will replace it.

BUT, respectfully, I don't agree that the charger was the likely source of the short. That charger internal shot shows the plating cooked off of the ground nut, but the positive nut is still plated, and seems to just have some smoke deposits from the black wire burning up. The red wire connected to the charger looks normal and unheated. Even its lug still has the plastic sleeve.

If the charger had been the source of the short, I would expect to see a lot more evidence of heating on that red wire and terminal, and some damage or obvious heating on the big semiconductors.
Lake-Effect is offline   Reply With Quote
Old 28-07-2020, 15:21   #27
Registered User
 
APWTryfan's Avatar

Join Date: Sep 2018
Posts: 44
Re: Electrical Fire - Seeking Help Please

Thank you good observation.

For clarity the 2 red wires ran from charger to B1 and B2 posts on switch. The black ground wire ran from charger to engine.

The switch was set to B2 when the short occurred.

Wrong that i) it was not fused and ii) that this circuit was live even though not in use.

Quote:
Originally Posted by JayH View Post
Look at that picture again. The positive wire has burned through the red insulation (which is all that is connected to the charger) and has fallen down the left side of the picture. The insulation has melted off the black wire all the way up to the charger. The charger definitely had an internal short.

That red wire break is likely what saved the boat.
APWTryfan is offline   Reply With Quote
Old 28-07-2020, 15:44   #28
Registered User

Join Date: Apr 2013
Location: So Cal
Boat: Catalina 30
Posts: 959
Re: Electrical Fire - Seeking Help Please

The first thing that happened is that your charger developed a pretty good dead short between +12 and gnd. Looking at the pic of the charger the board trace for gnd got dang hot. I'd guess the transformer/inductor looks like it got hot too - likely wore through some varnish in there I'd guess.

The second thing that happened is the fuse on the end of the charger blew. Wait, that didn't happen. The wire was the fuse and they tend to blow with smoke and fire.

1. Replace that charger, it's toast.

2. Fuse EVERY source. Solar, alt, and shore charger - if a wire shorts in the alt, and there's no fuse anywhere, the wire from the switch or batteries to the alt will fry (from the battery voltage, not the alt output) Same for the solar, sure your charger can only put out N amps, but if the solar controller shorts it's inputs, you'll dump all the battery can into the wires (and release the magic smoke...)

3. Fuse your batteries to handle the situation of a short from the battery to the A/B switch. (https://www.pbase.com/mainecruising/battery_fusing)

If #2 and/or #3 were done this incident would not be "glad we didn't burn to the waterline at sea!" to "why doesn't the shore power charge?"
jeepbluetj is offline   Reply With Quote
Old 28-07-2020, 16:24   #29
Registered User

Join Date: Jun 2008
Posts: 297
Re: Electrical Fire - Seeking Help Please

I missed the fact that there were two red wires and one black going to the charger. I looked at the charger manual and realized that the black had been removed before the picture was taken and that the scorched wire still connected to the charger was one of the reds.

The wire hanging down to the left of the charger must be the black. What does that end look like?

The black terminal in the charger looks clean. The wire was removed and the nut and lock washer were carefully placed back on the terminal without any mention that it had been done, which I find strange. Andy, did you do that?

I agree with Lake-Effect that there should be more damage inside the charger if it were the cause of the short.

Is it possible that the black wire had been removed from the post prior to the incident and left floating inside the charger? Then while the boat was underway it came in contact with the left red terminal and created the dead short at that burned terminal?
JayH is offline   Reply With Quote
Old 28-07-2020, 16:45   #30
Registered User

Join Date: May 2011
Location: Lake Ont
Posts: 5,572
Re: Electrical Fire - Seeking Help Please

Quote:
Originally Posted by JayH View Post
I missed the fact that there were two red wires and one black going to the charger. I looked at the charger manual and realized that the black had been removed before the picture was taken and that the scorched wire still connected to the charger was one of the reds.
... and now that I looked at the charger manual, I realize I'm out to lunch about what wire burnt, and that it was indeed a red wire that burned up. So, yeah, charger.

Isn't the internet fun??
__________________

Lake-Effect is offline   Reply With Quote
Reply

Tags
cal, electric, electrical, lease

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Electrical Fire Prevention from Fluke GordMay Electrical: Batteries, Generators & Solar 1 04-08-2020 18:11
HELP! Me Learn a New Language. Please. Please, please UNCIVILIZED General Sailing Forum 93 14-05-2017 09:03
Fire!! Fire:0, Mark:1, Extinguisher:?????? MarkJ Health, Safety & Related Gear 56 14-04-2014 16:02

Advertise Here


All times are GMT -7. The time now is 02:00.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.