Installing main power switch

[John in MN]

I want to install a main power switch to control the power to the accessories, i.e. lights, bilge pump, livewell pump etc. I'm doing this so if one of these switches gets bumped, it won't run the battery down. Is all I need to do is put the switch in-line on the main power wire coming from the batery before it reaches the dash board and all the accessories' switches?

[Tom]

John, That's right usually the Master Power switch gets put on the wire like you say just before the fuse panel if you have one. Happy Wiring Tom

[REW]

This is not a bad idea. However, remember that this is another source of potential battery failure.
Also, because - you will be running all of your non-motor things through this switch, including lights, pumps, electronics, etc. the switch needs to be a high quality waterproof switch of at least 30 and preferably 40 amps.
A normal 10 amp toggle switch - is really not up to this task. It is possible for a 10 amp switch to heat, and melt down (or cause a large voltage drop) if you have a heavy current -- like all your lights, stereo, cigarette lighter, spot light all running at the same time.

Good luck and take care

REW

[Randy Dalby]

If you want to do it right - go back to you battery - all of the wires that are connected to the positive terminal need to be switched - make sure the switch (as state earlier) is of adequate amperage.

[REW]

On this same subject -
I was at the local dealer yesterday and a person came in with a wiring problem -- he seemed to have some questions that the representative was unable to answer.

The previous post mentions -- switching "all" of the wires connected to the battery.

I suggest the following:

1. Remove all wiring from the battery.
2. If you have more than a single "wire - other than the motor starter cable and the main boat power feed wire" going to the battery fix it.
3. You fix it as follows:
a. Add a 40 amp circuit breaker to the + post of the starting battery. Now, on the +post of the starting battery you will have the main motor starting cable and the 40 amp circuit breaker.
b. Connect a single red 10 gauge wire to the 40 amp circuit breaker. Run this wire to your fuse block -- where ever it is located in the boat.
c. Connect a single black 10 gauge wire to the - terminal of the starting battery. Now, you will have only two wires connected to the - terminal. The - side of the motor starting cable and the black 10 gauge wire. Run this black wire to the ground side of the fuse block -- where ever it is located.
d. Run all boat functions from the fuse block. Lights, electronics, pumps, horns etc.

This makes a much cleaner and "safer" electrical installation. If you do have the misfortune of a chafed wire, or short before the fuse block, the circuit breaker will protect the intra boat wiring so that you don't get a melt down. Any time there is a battery changing, charging, or other maintenance item -- there is a single set of wires to remove from the battery. Tidy and neat and much easier to fix, in the event of a future problem.

Take care

REW

[Someday]

I like to have a bilge pump connected directly to the battery.

[REW]

Why?
Since the switch for the pump is on the dash?

take care

REW

[Confused?]

Ever seen an automatic bilge pump?

[Someday]

Yes. I have one. It needs to have power. I f it is connected to the load side of the switch and the switch is turned off, it won't run.

[Confused??]

My comment was directed to REW, Obviously.

[REW]

I understand your thoughts on the bilge pump and it does make sense.

I had considered that, since I have an automatic bilge switch as well. However, I did want a manual setting as well as a full off setting to insure that there is no battery discharge if the boat is being stored in a dry area.

Thanks for the update.

REW

[chadk66]

hey guys.
you all have some great advice. REW does bring up a good point in regards to the auto bilge situation. Something could lodge under the arm and it could run continually until, well you get the picture. I do have just one neat little thing to share in regards to the main buss. instead of having a fuse panel or regular circuit breakers, go down to napa and buy a self resetting circuit breaker. They are really cool and work great.

[LC/in/OH`]

On the Y2K Crestliners, we include the main power switch on our 17 degree V models. One thing we also do is make sure it does not cut off the main motor as well as the bilge pump. Just in case you have a wiring problem and have to hit the swtich out on the big water, you can still get home.

LC

[REW]

It is interesting to note that in the latest issue of Bassin magazine there is an article on boat maintenance. This article is written from a tournament fisherman to insure that he or she always has a servicable boat for every required run.

There was a considerable discussion on the installation of a master power switch. The comment that was made in the article -- especially with the installation of an automatic bilge switch -- enable a master off switch.
The comment continued by saying "There has been more than one storage facility caused by an automatic bilge pump starting and continuing to run, until it starts on fire, ignites the boat and burns down the storage facility.

Very timly topic for discussion.

Take care

REW

[Mark W.]

Since the boat that is in storage would not need any power to it's systems, and the batteries should be pulled for storage anyway, wouldn't the fire problem be easily solved by either disconnecting, and/or removing the batteries in the first place?

Just a thought,

Set the Hook!!

Lundman