Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 09-09-2013, 19:57   #1
Registered User
 
Dufour4800-175's Avatar

Join Date: Sep 2013
Posts: 11
Where to fuse??

Hello,

I recently starting to thing about rewiring my boat. Im a bit confused on where i have to put fuses to make a safe installation. Now I have a starting batt. And 2 6v batt. For house bank. I have a wire going to the dc pannel, and then all dc sources are fused individually. Do i have to add some fuses? Probably one to protect the wire coming out of the batteries?
__________________

__________________
Dufour4800-175 is offline   Reply With Quote
Old 09-09-2013, 20:05   #2
Senior Cruiser
 
skipmac's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: 29 49.16 N 82 25.82 W
Boat: Pearson 422
Posts: 12,379
Re: Where to fuse??

I think the best option is to use a fuse right on the battery terminals, like the Bluesea systems fuse blocks. The cables to your DC panel attach to the fuse block so you are protected right to the battery. You can get single and double blocks and different rated fuses up to 200-300 amps.
__________________

__________________
The water is always bluer on the other side of the ocean.
skipmac is offline   Reply With Quote
Old 12-09-2013, 13:34   #3
Registered User
 
Dufour4800-175's Avatar

Join Date: Sep 2013
Posts: 11
Thanks for this answer im gonna look that way!
__________________
Dufour4800-175 is offline   Reply With Quote
Old 12-09-2013, 14:02   #4
Senior Cruiser
 
skipmac's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: 29 49.16 N 82 25.82 W
Boat: Pearson 422
Posts: 12,379
Re: Where to fuse??

Here's links to the battery fuse blocks, single and double versions.

Blue Sea Systems Terminal Fuse Block

Blue Sea Systems Terminal Fuse Block

The single fuse photo is the bare connector. The photo on the double connector block shows the fuses installed.

Here's a link to the fuses. They come in lots of amp ratings.

Blue Sea Systems Terminal Fuse
__________________
The water is always bluer on the other side of the ocean.
skipmac is offline   Reply With Quote
Old 12-09-2013, 14:18   #5
Senior Cruiser
 
rebel heart's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Posts: 6,190
Images: 3
Re: Where to fuse??

My wiring looks something like this:

(starter battery)---->(starter bus bar)
(house batteries)---->(house bus bar)

I don't have a switch to switch the starter motor from the starter battery to the house; I don't need it and if I ever do it would take 30 seconds to unscrew a wingnut. Anyway, I have two fuses:

1) Between the starter and the starter bus block, rated at 150 amps. My starter motor says it takes 125 amps. So if I hit 150 (thermal), there's a serious problem.

2) Between the house bank and the house bus block, rated at 100 amps. Theoretically I could max that out if I was transmitting on the SSB at the same time somone was flushing the toilet at the same time someone was running a heat gun off the inverter. The odds of all that happening are obviously pretty slim.

Anyway, that's how I have mine fused. All the smaller circuits are run through the breaker panel, so every circuit is fused or or circuit breaker protected.

While you're doing all of this, consider putting a smoke (not co) detector in the battery compartment itself. If there's a fire in there it will be fully involved before the smoke will get out into the cabin. Cheap $20.
__________________
rebel heart is offline   Reply With Quote
Old 12-09-2013, 15:39   #6
Registered User
 
Dufour4800-175's Avatar

Join Date: Sep 2013
Posts: 11
Re: Where to fuse??

thanks for the links!
And good idea for the smoke detector!

Im ordering fuses tonight!
Alex
__________________
Dufour4800-175 is offline   Reply With Quote
Old 12-09-2013, 15:45   #7
cruiser

Join Date: Feb 2011
Location: medusa NY
Boat: Tayana Surprise 45 schooner "Union Pacific"
Posts: 2,098
Re: Where to fuse??

i may take heat for this, but do not use a fuse on your bilge pump.
run direct to the battery. no fuse at all.
__________________
scoobert is offline   Reply With Quote
Old 12-09-2013, 16:09   #8
Senior Cruiser
 
skipmac's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: 29 49.16 N 82 25.82 W
Boat: Pearson 422
Posts: 12,379
Re: Where to fuse??

Quote:
Originally Posted by scoobert View Post
i may take heat for this, but do not use a fuse on your bilge pump.
run direct to the battery. no fuse at all.
Very bad advise. If the bilge pump jams from a small piece of debris it can overheat and start a fire.

DO fuse the bilge pump, always!

What you should do is run at least one bilge pump directly to an always hot connection, even directly to the battery so you will not inadvertently turn off the bilge pump when you turn off power at the main switch or DC panel. Just make sure that direct connection is fused!
__________________
The water is always bluer on the other side of the ocean.
skipmac is offline   Reply With Quote
Old 12-09-2013, 16:12   #9
Senior Cruiser
 
Sailmonkey's Avatar

Cruisers Forum Supporter

Join Date: Sep 2009
Location: Houston
Boat: '76 Allied Seawind II, 32'
Posts: 5,775
Quote:
Originally Posted by scoobert View Post
i may take heat for this, but do not use a fuse on your bilge pump.
run direct to the battery. no fuse at all.
Always fuse a bilge pump, but size the wire and fuse properly so the running of the pump does not blow the fuse.
__________________
Sailmonkey is online now   Reply With Quote
Old 12-09-2013, 16:18   #10
Senior Cruiser
 
skipmac's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Location: 29 49.16 N 82 25.82 W
Boat: Pearson 422
Posts: 12,379
Re: Where to fuse??

Here is a quote from a previous thread about fuses for bilge pumps here Fuses Needed to Comply with ABYC Rules. I assure you Charlie knows what he's talking about.


During seminars, I will deliberately overfuse a small Rule centrifugal pump, jam the impeller with a screwdriver and then apply power and continue the lecture. Within about 10 to 15 minutes the pump starts to smoke. NOTE: THE FUSE NEVER OPENS DURING THIS DEMO! And this is why marine equipment manufactures are required to provide the fuse rating for their rotating equipment.

Here is the applicable section from the ABYC E-11 Standard:

11.10.1.2.1 Motors and motor operated equipment, except for engine cranking motors, shall be protected internally at the equipment, or by branch circuit overcurrent protection devices suitable for motor current. The protection provided shall preclude a fire hazard if the circuit, as installed, is energized for seven hours under any conditions of overload, including locked rotor.
NOTES:
1. It may be necessary to use thermally responsive protection devices on the equipment or system if the motor is not capable of operating continuously at maximum possible loading.
2. It may be necessary to test as installed in order to assure compliance with the locked rotor requirement. Voltage drop, due to wire size, and delay characteristics of the overcurrent protection device may have to be adjusted to protect the motor.

In the case of the Rule 500, if it was a 12VDC model, the technical specification is to protect it with a 2.5A fuse or circuit breaker. Rule 500 > ITT Flow Control - Engineered for life.

There is generally a lot more to this stuff then meets the eye.

Charlie will now relinquish his soapbox.

Hope this helps.
Charlie
__________________
Charlie Johnson
JTB Marine Corporation
__________________
The water is always bluer on the other side of the ocean.
skipmac is offline   Reply With Quote
Old 13-09-2013, 17:44   #11
Registered User
 
Dufour4800-175's Avatar

Join Date: Sep 2013
Posts: 11
Okay!! Thanks for the replys! I now have to install fuses and do some testing!
__________________
Dufour4800-175 is offline   Reply With Quote
Old 19-09-2013, 23:35   #12
Registered User
 
Yeti's Avatar

Join Date: Apr 2008
Location: San Diego
Boat: Cascade 36
Posts: 246
Re: Where to fuse??

Battery Bank Fusing Photo Gallery by Compass Marine at pbase.com

The above is a great little article on the subject of battery fusing. Covers it really well.
__________________

__________________
Yeti is offline   Reply With Quote
Reply

Thread Tools
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




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 14:17.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.