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Author Topic:   In-line Fuse
1985supersport15 posted 05-13-2008 11:57 AM ET (US)   Profile for 1985supersport15   Send Email to 1985supersport15  
Where to install an in-line fuse for a [combination SONAR, chart plotter, and GPS receiver]? Some say on positive line near the unit; others say you want to be on the positive line near the battery. I hear rumor that near the battery can cause a spark and ignite gas fumes or battery gasses. Is this a reasonable risk you run? Others say the spark would be in the fuse and in the holder and is well covered.

Also, the power cord is 18-AWG stranded wire. Can I use a 14-AWG in-line fuser holder? I have heard you can get away with going up a few gauges but obviously can't go down. Will [using a fuse holded that has 14-AWG wire in a circuit which uses 18-AWG wire] cause any problems? West Marine and other marine suppliers had 14-AWG wire. It was the closest to the appropriate [wire current carrying capacity] I need.

Thanks

Chuck Tribolet posted 05-13-2008 06:19 PM ET (US)     Profile for Chuck Tribolet  Send Email to Chuck Tribolet     
[Locate the fuse in a circuit] as close to the battery as possible. If the power line gets shorted, you want the fuse to blow, and it won't if the short is between the battery and fuse.


Chuck

jimh posted 05-13-2008 07:50 PM ET (US)     Profile for jimh  Send Email to jimh     
In a power distribution scheme, branch circuits should be protected by a fuse which is suitable to protect the wiring used in the branch circuit. If a circuit is wired with 14-AWG wire, the circuit should be protected with a fuse with a rating that is no larger than the maximum current that the 14-AWG conductors can carry. However, it is not a problem to install a fuse with a rating that is lower than the maximum rating of the conductors of the branch circuit.

In the case of an individual device with an in-line fuse in its power cord, the fuse should be chosen to have a rating which is just slightly higher than the maximum current the device will draw. There is no problem if the circuit is wired with large size cable. The in-line fuse can have a much lower rating than the current capacity of the wire.

It is often seen that a circuit is wired with large gauge wire in order to reduce the voltage drop in the circuit to the absolute minimum. However, the circuit may be protected with a fuse with a much lower rating, if that fuse is appropriate to protect the equipment being operated on that circuit.

In-line fuses are usually located close to the device they are protecting. Fuses which protect a branch circuit are usually located as close to the source of power as possible

1985supersport15 posted 05-13-2008 11:01 PM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
Manufacturer recommends 3 amp fuse. The power wire is 18 gauge multistrand. If I understand correctly the 14 gauge wire on the in line fuse holder should not cause a problem? or should I go down gauge rather than up to say 18-22. I had trouble matching the gauge for the fuse holder wire because they were not water resistant holders.

I am a little confused as to locating fuse holder near the unit or battery. There were a few comments about this that were contradictory. I was concerned when someone told me a spark from the fuse could cause battery gasses or fuel vapors to ignite. Obviously I'd also like to locate it which ever place will prevent overvoltage more effectively.

Alternatively you mentioned a fuse panel of some sort? Not sure how to wire that to my existing ignition wires (closest powersource to the side console).

Reson manufactures 6ft cable doesnt reach is my battery and ciruit box are on the port side of the boat opposite the console.

jimh posted 05-14-2008 09:17 AM ET (US)     Profile for jimh  Send Email to jimh     
If you are still unclear about the relationship between wire size and fuse size, please re-read my reply above.
jimh posted 05-14-2008 09:20 AM ET (US)     Profile for jimh  Send Email to jimh     
Fuses should be placed near the device they are protecting. Fuses which protect branch circuits are placed close to the source of current for those branch circuits. Fuses which protect individual devices are placed close to the individual device. It is quite common that the fuse which protects an individual device be placed inside the device, since that is about as close to the device as you can get. Devices which do not have internal fuses and are protected with in-line fuses in their power cords usually have the in-line fuse placed close to the device. The purpose of an in-line fuse attached to a device is to protect the device, not to protect the power distribution.

Attaching multiple connections to a battery terminal is not a recommended practice, although it is often seen in small boats.

1985supersport15 posted 05-14-2008 02:03 PM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
If the [Global Position System] power is the only wiring going to the battery in addition to the ignition wires, is that too much [wiring going to the battery]?

I looked at circuit boards and busses today at [a marine supply store] but none of them have covers since they all expect inside cabin use. Also besides the [Global Positioning System] power, I do not anticipate connecting any other devices in the front of the boat.

Is marine grade cable that I would buy at [a marine supply store] waterproof like [manufacturer's] power cable? Or would you recomend buying another 6-foot cable from [the manufacturer] and connecting those [two cables together]?

jimh posted 05-14-2008 06:06 PM ET (US)     Profile for jimh  Send Email to jimh     
"Is marine grade cable...waterproof?"

Yes.

jimh posted 05-14-2008 07:41 PM ET (US)     Profile for jimh  Send Email to jimh     
Actually the terms "waterproof" and "marine grade" are not well defined and are somewhat amorphous. There are Underwriter's Laboratory ratings (UL-Ratings) and other classification society grades for electrical cable which are used to specify wire suitable for use in marine applications. The federal government also weighs in on this topic in its published regulations.

"Waterproof" can mean many things. The precise nature of the resistance of a wire insulation to penetration by water is better defined in the standards.

But, all that said, it is more or less a foregone conclusion that "marine grade" wire (which may be a self-assigned classification by the manufacturer) is going to be suitable for use in a marine application (where the presence of water is more or less assumed).

There is a good prior discussion about marine grade wire, who supplies it, what standards it meets, how much it costs, and where to buy it:

Marine-Grade Wire: A Price Survey; Recommended Sources
http://continuouswave.com/ubb/Forum6/HTML/001447.html

If you are interested in locating marine grade wire, I am certain that you will find that reading this prior discussion will be beneficial.

jimh posted 05-14-2008 07:49 PM ET (US)     Profile for jimh  Send Email to jimh     
"...would you [recommend] buying [marine grade wire from] [Humminbird]...?

No. See above for a link to an article that contains recommended vendors of marine grade wire.

davej14 posted 05-15-2008 07:50 AM ET (US)     Profile for davej14  Send Email to davej14     
Supersport,

If you only have two wires going to your battery I would not be concerned. In that case putting your in-line fuse holder next to the battery to protect the circuit AND the device would be the preferred location. If you cannot match the wire size of the fuse holder's leads to your circuit wiring then going to a larger size conductor is perfectly acceptable. Be sure you make a good connection to the fuse holder. I prefer to use Anchor crimp splices with the adhesive lined heat shrink over them. Others prefer to solder and then cover with adhesive lined heat shrink.

If you want to spend a few dollars and do a more professional job, I recommend using a power distribution block from Blue Sea systems. This block is of high quality and comes with a cover.

http://bluesea.com/category/5/21/productline/126

I usually cut off the in-line fuse that comes with equipment and use just a similarly rated fuse in the fuse block circuit that services the equipment. It probably voids the warranty on the equipment but if a fuse blows I know where it is and do not have to find it in a wire harness. On the other hand, there is no harm from having two fuses in a circuit.

Sparks are never a good thing around a battery in an enclosed space but a blown fuse element is unlikely to cause a problem as it is contained within the fuse body. One of the reasons I prefer to use sealed batteries is to minimize the risk of hydrogen gas build up.

1985supersport15 posted 05-15-2008 01:38 PM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
Thanks Dave,

If I decide to take the circuit box route what gauge wire would I use from the battery to the circuit box? Again all I would be running from the console is the GPS and my running lights switch.

davej14 posted 05-16-2008 12:11 AM ET (US)     Profile for davej14  Send Email to davej14     
I would be running 10 gauge from the battery to the console. This is overkill for your intended application but once you have the fuse block installed you are bound to add equipment to it in the future. If there is a marine outlet in your area that sells anchor duplex wire by the foot it makes for a clean installation. If you cannot get the duplex wire then single conductor is equally good electrically just not as pretty. Definitely use Anchor brand wire designed for marine use.
swist posted 05-16-2008 02:07 PM ET (US)     Profile for swist  Send Email to swist     
1985supersport15: You are causing a bit of confusion here by continuing to refer to a DC distribution device as a circuit *board*. A circuit board is usually something interior to a piece of electronic equipment - you would normally never even see it or fiddle with it, and it has no part of this discussion.

The usual term is "circuit breaker panel" or "fuse panel". If it does not have fuses or breakers then it's a "bus bar" or "distribution bus" or some such thing.

jimh posted 05-16-2008 08:54 PM ET (US)     Profile for jimh  Send Email to jimh     
In an ideal construction, only one terminal is placed beneath each post or connector. However, in small boat installations it is often seen that more than one terminal is connected to a battery terminal post.

The word "buss" means a kiss.

Electrical circuits are often wired to a bus.

"GPS" means Global Positioning System.

swist posted 05-17-2008 08:44 AM ET (US)     Profile for swist  Send Email to swist     
Spell the singular and plural of the following words that sound like bus or buss.

1) A vehicle used to carry many people.
2) An electrical term
3) A kiss

I can't do it.

jimh posted 05-17-2008 09:31 AM ET (US)     Profile for jimh  Send Email to jimh     
As requested:

"While taking my usual route (or circuit) to the marine store to buy electrical bus bars for my boat's positive and negative electrical buses, I saw three city buses passing on which couples were exchanging busses.

Riverwhaler posted 05-17-2008 09:45 AM ET (US)     Profile for Riverwhaler  Send Email to Riverwhaler     
As jimh is usually correct in his analysis I hesitate to step in here but...a fuse or circut breaker is supposed to protect not only the device but also the branch circut. So it should be as close to the supply of electricity as possible. Your house wiring is a good example. So the fuse should be as close to the battery as practible. That being said my Whaler has a larger circuit breaker feeding a distribution panel with fuses to supply various devices. Just like the house. It is sometimes confusing to novices that the larger the number gauge the smaller the wire size.
jimh posted 05-17-2008 10:42 AM ET (US)     Profile for jimh  Send Email to jimh     
There are fuses which protect the branch circuit, and there are fuses which protect the individual device. The fuses are for different purposes, the fuses are in different places, and the fuses have different ratings.

It is quite common that an electrical device protect itself with a fuse. The fuse that does this is located close to the device, and the rating of the fuse is selected to be appropriate for the current the device will need when it is operating normally. If the device operates in an abnormal manner and draws excessive current, it will blow its fuse. For example, a VHF marine radio draws 7-amperes during transmit. The power cord is fused with a 7.5-ampere fuse. When operating normally this fuse will not blow. If the radio malfunctions and operates abnormally by drawing excessive current, the 7.5-ampere fuse will blow.

A branch circuit can supply many loads. The branch circuit is fused for the current that is expected to be drawn by the total of all the loads on that circuit. The rating of the fuse must not exceed the rated capacity of the wiring used for the branch circuit. If I have a branch circuit wired with 10-AWG wire, I can fuse it for 30-amperes.

It might happen that I have my VHF marine radio connected to a branch circuit fed with 10-AWG wire. If there were no fuse in the radio, if the radio malfunctioned, and if the radio drew 25-amperes of current, a lot of damage might occur to the radio and the fuse in the branch circuit would never blow.

In 12-volt DC wiring practice it is a good idea to provide over-current protection very close to the battery itself for any conductor connected to the battery. The exception to this is usually the primary battery cable to the engine cranking motor, which in most cases is not fused. However, usually there is a shut-off switch located very close to the battery which can be operated to stop current flow in an emergency.

Riverwhaler posted 05-18-2008 10:43 AM ET (US)     Profile for Riverwhaler  Send Email to Riverwhaler     
So see I should have known better. One needs to follow ones instincts. Jim, most everything I know about wiring I learned from my father in law. Once again you are explicitly correct but not my father in law.
jimh posted 05-20-2008 11:59 PM ET (US)     Profile for jimh  Send Email to jimh     
I don't think I am old enough to be your father-in-law.
Riverwhaler posted 05-21-2008 07:46 AM ET (US)     Profile for Riverwhaler  Send Email to Riverwhaler     
More likely I am older.
1985supersport15 posted 05-23-2008 11:33 AM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
Thanks for all the feedback with regard to this issue.

After taking apart my side console and my woodwork for maintenance I realized I do have a power supply to the console. It is setup as follows:

There is a brown distribution box on the rear port side of the boat. If I connect the wires from the box to the battery other heavily insulated wires run from the box to the console. These wires look like 18 gauge or a little more I am not absolutlely sure.

I used a volt meter and did get power at the console but it was only 7 volts or so and the battery terminals registered 12 obviously. I was not sure if poor contacts would cause the drop in voltage or if that brown distribution box distributed the current. Either way I wanted to know if I can run my fishfinder off less than 12 volts or if cleaning the contacts on both ends might give me more power.

That said is the easiest most professional way to connect my fishfinder to connect a fusepanel to my powersource at the console then connect the fishfinder to that?

West marine had distribution boxes and buses but they had no covers and the busbars did not have fuses. Someone mentioned blue sea as a vendor and it seems their six circuit box might do me well as all I will have running off this will be my fishfinder and a running lights switch.

The wires that run to the console have a positive, negative and a ground wire and I was not sure if the ground wire was/ is necessary or if it was in place simply because it was originally connected to a running light switch.

seabob4 posted 05-23-2008 11:46 AM ET (US)     Profile for seabob4  Send Email to seabob4     
The reading of 7V DC at the helm is a result of serious corrosion in your wiring going forward. If you strip back some insulation, especially at the transom end, I'm sure you'll find the exposed wire is black. The resistence caused by this will result is a significant voltage drop, as you are seeing. Sounds like it's time to run new wiring. I have two braker modules (I'm not a fuse guy) made by BEP Marine (far better than Blue Seas) that I [offer for sale].
1985supersport15 posted 05-24-2008 10:01 AM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
I would like to see a picture of the breaker modules if you have one. How do [circuit breakers] work protecting the unit as compared to a fuse box setup?
Thanks, AC
jimh posted 05-25-2008 08:17 AM ET (US)     Profile for jimh  Send Email to jimh     
Circuit breakers and fuses are both over-current protection devices. Both fuses and circuit breakers respond to over-current by opening. In the case of a fuse its operation is a one-time event, while circuit breakers are usually rated for hundreds of over-current circuit interruptions. Some circuit breakers are also intended to be operated manually as part of a control of the circuit they protect. Circuit breakers are also much more expensive than fuses, and they take up more room.

Some fuses will react faster to over-current than some circuit breakers.

Circuit breakers and fuses in a distribution panel are intended to protect the branch circuit that is connected to them. They are not protecting the individual devices attached to the branch circuit. If only one device is attached to a branch circuit, and the fuse or circuit breaker is selected to have a current rating that is exactly matched to the device, then the fuse or circuit breaker can be considered to be protecting both the branch circuit and device. Most devices include some sort of over-current protection within the device, usually a fuse. In some cases the fuses are internal and not intended to be serviced by the user.

1985supersport15 posted 05-28-2008 11:28 PM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
Decided to take the inline fuse route instead of a fusepanel as I only need to power my fishfinder and then my running lights switch. I have about 5 questions here and after this no one should have to put up with my ignorant wiring questions.

I bought 12 ft of 18gauge awg at west marine to connect to the existing 6 ft humminbird cable so I can reach the battery. Many advised me to put the in line fuse on the positive wire close to the fishfinder.

How close is best to put the fuse to the fishfinder. Is 6ft ok or should I cut the humminbird cable to a foot or so length from the fishfinder and then connect it to the 18 gauge awg with the in line fuse in between?

The in line fuse I purchased is in a loop and I am assuming I cut the loop at its midpoint and then connect it. Is it ok to cut the length of the in line fuse wire down so that it is 2 or three inches instead of about one foot?

That way I do not need to strip back the 18gauge awg too far to accomadate the long in line fuse splice in.

Also what is the best way to make the connection?
Ive considered 18gauge rated heatshrink butt connectors. I understand you simply crimp the wires in place then close the heatshrink with a lighter or some other heat source. Is that enough or would you put heat shrink tubing over the butt connectors as well or use liquid electrical tape to seal it better.

Lastly, to connect the 18gauge awg to the battery would you just use 18 gauge rated terminall loops that have heat shrink?

Thanks, AC

1985supersport15 posted 05-28-2008 11:29 PM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
Decided to take the inline fuse route instead of a fusepanel as I only need to power my fishfinder and then my running lights switch. I have about 5 questions here and after this no one should have to put up with my ignorant wiring questions.

I bought 12 ft of 18gauge awg at west marine to connect to the existing 6 ft humminbird cable so I can reach the battery. Many advised me to put the in line fuse on the positive wire close to the fishfinder.

How close is best to put the fuse to the fishfinder. Is 6ft ok or should I cut the humminbird cable to a foot or so length from the fishfinder and then connect it to the 18 gauge awg with the in line fuse in between?

The in line fuse I purchased is in a loop and I am assuming I cut the loop at its midpoint and then connect it. Is it ok to cut the length of the in line fuse wire down so that it is 2 or three inches instead of about one foot?

That way I do not need to strip back the 18gauge awg too far to accomadate the long in line fuse splice in.

Also what is the best way to make the connection?
Ive considered 18gauge rated heatshrink butt connectors. I understand you simply crimp the wires in place then close the heatshrink with a lighter or some other heat source. Is that enough or would you put heat shrink tubing over the butt connectors as well or use liquid electrical tape to seal it better.

Lastly, to connect the 18gauge awg to the battery would you just use 18 gauge rated terminall loops that have heat shrink?

Thanks, AC

jimh posted 05-28-2008 11:45 PM ET (US)     Profile for jimh  Send Email to jimh     
Ring terminal connectors are sold with two parameters:

--the size of wire they accommodate, usually in a range of 10 to 12-AWG (yellow insulation), 14 to 16-AWG (blue insulation), and 18 to 22-AWG (red insulation), and

--the size of terminal stud they fit over, often also in ranges of various size.

You select the ring terminal connector based on the size of the wire and the size of the terminal stud. There are many permutations available.

Riverwhaler posted 05-29-2008 08:23 AM ET (US)     Profile for Riverwhaler  Send Email to Riverwhaler     
Once again I step in cautiously. I think you should put the fuse close to the supply so as to protect the length of wire going to the device as well as the device itself.
jimh posted 05-29-2008 09:40 AM ET (US)     Profile for jimh  Send Email to jimh     
I concur. I would place the in-line fuse at the end of the cable so that there was only one splice; the other end of the fuse's wire can have a terminal installed and go right to the battery terminal post. This eliminates a splice.

If the fuse is provided wired in a loop of wire, you cut the wire. This allows you to select the lead length that results. The fuse goes in the positive lead.

The reason the fuse is preferred in the positive lead is due to consideration for galvanic corrosion. If a fuse opened the negative side of the circuit, the device might be still connected to the battery positive, which would tend to enhance any galvanic corrosion if anything associated with the device is in contact with water. Fusing the positive lead is also the usual practice in wiring DC circuits in which the negative battery terminal is the common or ground.

About the only time you see a fuse in the negative lead is in devices wired into vehicles where the metal chassis or car body is used as the return for the negative lead of many circuits, and the device being fused is connected to something that is also bonded to the chassis. This happens in the case of a radio transmitter where the antenna is bonded to the chassis of the vehicle. An extra fuse is placed into the negative lead of the transmitter power leads in order to prevent the radio antenna and the radio chassis from becoming the primary conductor of current from the battery negative to the chassis of the vehicle in the event that the normal conductor which bonds those two might fail. Under engine cranking this could cause a very high current to flow on the antenna transmission line shield and damage the antenna, the transmission line, or the radio transmitter. On a fiberglass boat this situation is not obtainable, so there is no need for a fuse in the negative lead.

davej14 posted 06-02-2008 08:21 AM ET (US)     Profile for davej14  Send Email to davej14     
An "Anchor" brand crimp butt splice with adhesive lined heat shrink should be adequate. Make sure you use a crimping tool designed for insulated connectors. This tool will deform the insulating sleeve when making the crimp but will not puncture it.
1985supersport15 posted 06-04-2008 09:20 PM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
Jim,
Curios as to why you now say it is ok to put the in line fuse close to the battery(probably inside the battery box. I was under the impression that this could create a hazard with the battery and gas tank nearby as the fuse could produce sparks.

I will have to splice the original 6ft humminbird cable at least once because it is not long enough to reach the battery. I am just trying to determine where the best place for the fuse would be with regard to protecting the fishfinder. I thought the cleanest way would be to connect the original 6 ft humminbird cable to the west marein 18 gauge multistrand (with the in line fuse at this connection) I figured I could coil any extra of the 6 ft cable under the console. I would then run the connection length to the battery and use heat shrink ring terminals.

I am just confused if I need to "protected the length of wire from the battery to the fishfinder" or if having the in line fuse a few feet from the device (or about 6 feet away would be ok)

jimh posted 06-04-2008 10:09 PM ET (US)     Profile for jimh  Send Email to jimh     
1985supersport15 writes:

"Curios (sic) as to why you [i.e., me, jimh] now say it is ok to put the in-line fuse close to the battery(probably inside the battery box. I was under the impression that [locating a fuse near a battery] could create a hazard with the battery and gas tank nearby as the fuse could produce sparks."

You are under the wrong impression. I do not hold the same view as you do, so it is not inconsistent for me to recommend that you locate a fuse near the battery. That position is only inconsistent with your view of electrical safety, not mine.

Please give a citation of where someone with some authority or recognized standing as an electrical safety expert has given you the advice that you must not locate an Underwriters Laboratory approved fuse near a battery.

1985supersport15 posted 06-06-2008 07:34 AM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
My knowledge of electronics is minimal. I am merely confused as to why you previously recommended installation closer to the unit and now advised me that closer to the battery is a better place because it protects not only the gps but also the length of wire leading to it.
jimh posted 06-06-2008 07:30 PM ET (US)     Profile for jimh  Send Email to jimh     
I did not instruct you where to place a specific fuse for a specific instance. I gave advice about the general location of fuses, particularly those which protect branch circuits.

It is very poor practice to connect any distribution wiring directly to a battery which is not fused at the battery.

You have not provided any citation or reference for the advice which you passed along about the explosion hazard of locating a fuse near a battery. Since the risk of an explosion is important to avoid, I think that it is important that you disclose the source of this advice. It is not prudent to have conflicting and unresolved advice about something that could lead to an explosion.

1985supersport15 posted 06-08-2008 10:52 AM ET (US)     Profile for 1985supersport15  Send Email to 1985supersport15     
Irregardless of the apparent rumor I have heard about explosion hazards I simply wanted to know the best place to put the fuse in order to protect the fishfinder whether it be near the power source or the fishfinder. The reason I this is unclear is because you advised me to put it closer to the device I am protecting and recently changed the location to closer to the power source. I just want to understand why this is the better location as someone alluded to it protecting the device and the lenght of wire leading up to the device.
Chuck Tribolet posted 06-08-2008 12:46 PM ET (US)     Profile for Chuck Tribolet  Send Email to Chuck Tribolet     
The fuse does not protect the equipment (chartplotter), it
protects the wiring. To do that, it needs to be near the
battery.

But I think IN the battery box is a bad idea. The battery box
can concentrate hydrogen a bit. Remember the Hindenburg?
I'd put it right outside.


Chuck

davej14 posted 06-08-2008 01:06 PM ET (US)     Profile for davej14  Send Email to davej14     
1985supersport15,

All the advice you have received is excellent. I think you are confused about where to put the fuse because you misunderstand the "language". I will try to simplify this for you.

An overcurrent protection device such as a fuse will not protect aganist a short circuit in the portion of the wire that is between it and the battery. That is because any short in this segment will not cause current to flow in the fuse.

Since the equipment you are protecting is at the end of the circuit you can chose to place the fuse anywhere and the equipment will be protected. If that is your only consideration then you will want to size the fuse to the expected current draw of the equipment.

On the other hand, if you want to protect the majority of the wire as well as the equipment then placing the fuse closer to the battery will accomplish that. Since you will only have one wire for your equipment you should still size the fuse to the expected current draw of the equipment.

If you were to power multiple devices from a single wire then you would size the fuse to the capacity of the wire. Again, locating this fuse close to the battery will protect the largest portion of the circuit. In this case the fuse will be too large to protect any individual device so you would also need to have a fuse located near each device that is sized to the expected current draw of the device. In this configuration if one device blows its associated fuse the other devices will still function.

I will defer to other experts regarding the potential for explosions due to hydrogen gas from a battery. Although I have no experience in this area, logically a sealed battery should minimize this risk.

Bottom line is wire up your device, enjoy the season and don't lose sleep over this relatively simple installation.

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