Adding a fuse block - 6 circuits with negative bus

[JGator]

Adding the fuse block to run VHF, FM, Hummingbird and LED lights. Want to get these on their own wiring and circuit and switches and off the main power. Where should I mount the fuse block, closest to battery and run multiple wires pairs from fuse block to equipment or closer to equipment to be powered and run 6 awg from battery?

 

[minuteman62-64]

Electrically it doesn't make much difference, as long as wire sizes are appropriate for load/run. For convenience/organization, IMO, better closer to equipment being powered.

 

[Grandad]

Adding the fuse block to run VHF, FM, Hummingbird and LED lights. Want to get these on their own wiring and circuit and switches and off the main power. Where should I mount the fuse block, closest to battery and run multiple wires pairs from fuse block to equipment or closer to equipment to be powered and run 6 awg from battery?

You're probably best to install a main fuse close to the battery and place the fuseblock just before the switches close to where you want to conveniently control the devices. I think maybe you're over-engineering the wire size at # 6 AWG. I wouldn't use larger than #10 AWG as the main feeder for what you list up to at least 25' long. You'll find that when you exceed #10, all of the terminals are somewhat more difficult to acquire (both price and availability). A #6 AWG can add significant mechanical stress to terminals designed for terminating smaller wires, especially in a boat that vibrates and gets slammed around on waves. - Grandad

 

[gm280]

I have to agree with granddad. Use some 10 gauge wire and run it from the battery to the buss bars (positive AND negative) at the helm of the boat. Install a circuit breaker or fuse at the battery to protect against any possible wire chafing and short. And then at the buss bar run each circuit on its own fuse or circuit breaker for the accessory it will supply as well. For instance, if the circuit goes to the bilge pump, use a five amp fuse or breaker (or whatever size the manufacture suggests). If the circuit goes to the navigation lights, use another 5 amp fuse or circuit breaker to protect that circuit. If it goes to the fish finder, use another fuse or circuit breaker that the manufacturer suggests. That way if you do have any problems in one circuit the others still work without problems... That way you have everything covers like it is supposed to be wired... JMHO!

 

[Silvertip]

You won't be installing the new panel "off" the main power since the main power is the battery the other circuits are on. I always question why folks want to add switches for devices that already have a power on/off switch. If you are forgetfull, then use just one of the switches as the MASTER power switch for everything connected to that panel such as your VHF, radio, locator etc. Then one switch kills or applies power to that panel instead of having to flip a bunch of switches. It also eliminates a bunch of additional potential points of failure.

 

[JGator]

You won't be installing the new panel "off" the main power since the main power is the battery the other circuits are on. I always question why folks want to add switches for devices that already have a power on/off switch. If you are forgetfull, then use just one of the switches as the MASTER power switch for everything connected to that panel such as your VHF, radio, locator etc. Then one switch kills or applies power to that panel instead of having to flip a bunch of switches. It also eliminates a bunch of additional potential points of failure.

Thanks.

 

[JGator]

You won't be installing the new panel "off" the main power since the main power is the battery the other circuits are on. I always question why folks want to add switches for devices that already have a power on/off switch. If you are forgetfull, then use just one of the switches as the MASTER power switch for everything connected to that panel such as your VHF, radio, locator etc. Then one switch kills or applies power to that panel instead of having to flip a bunch of switches. It also eliminates a bunch of additional potential points of failure.

Actually that is close to what I'm doing, getting these devices off of other switches the previous owner had the circuits running through. Also had some running through the ignition switch, with more than one coming off that breaker and switch So yes an xtra run of #10 off the 'main supply' (battery) to a new fuse block in the helm then to each unit and not going through any other switched circuits at the helm. Have a master 1-2-both-off switch at the battery already and the new wires will run through as well. *Their own switch means the one on the unit, not another added switch on the helm panel the way its currently wired.

 

[gm280]

I can concur with Silvertip's thinking only IF you still have individual fuses or circuit breakers for each sub-circuit. Why? Because if you wire everything via one switch and one of the multiple circuit does have a problem/short, it will make all the other circuits on that same wiring setup no longer usable. So individual fuses or circuit breakers is a must for proper wiring safety. NO house has one large switch for everything in the house. And that is because each room can work by itself if another room has problems. Individual circuit switches are proper wiring techniques to allow a shorted circuit to be removed from all the other circuits via a fuse, breaker or switch... JMHO!

 

[JGator]

I can concur with Silvertip's thinking only IF you still have individual fuses or circuit breakers for each sub-circuit. Why? Because if you wire everything via one switch and one of the multiple circuit does have a problem/short, it will make all the other circuits on that same wiring setup no longer usable. So individual fuses or circuit breakers is a must for proper wiring safety. NO house has one large switch for everything in the house. And that is because each room can work by itself if another room has problems. Individual circuit switches are proper wiring techniques to allow a shorted circuit to be removed from all the other circuits via a fuse, breaker or switch... JMHO!

As mentioned each device comes off its on fuse on the new block and each unit has a on-off switch. I'm not sure where I gave the impression I was running everything through a single switch, single circuit other than going through the Blue Sea (Blue Sea Systems e-Series 9001e Selector 4-Position Battery Switch) 1-2-both-off switch at the battery to the new 6 fuse block. I've already finished the job and everything is working well. It's a 6 fuse 6 circuit block designed to distribute to six devices all fused with an ATC fuse. (Blue Sea Common Sourced ST Blade Fuse Block - 6 Circuits w/Cover & Negative Bus)

 

[Silvertip]

I see both you and GM280 misinterpreted my logic. Using one of the switches on your new panel would merely supply or cut power to the rest of the switches on that panel. It is not intended to power every device directly. In fact that scheme is very much like your house wiring in that the MASTER is the MAIN breaker in your breaker panel. It powers the other breakers which in turn powers each circuit. My contention is also that why switch a device that already has a power switch. You now have to hit two switches to turn on any switched device. With a MASTER switch the panel is now powered. Turn on any device at the device rather than having to hit a separate panel switch first. Devices like bilge pumps, lights, etc need a separate switch. Radios, locators, GPS units do not. But -- it's your boat, do whatever lights your fire. There is nothing unsafe about using a MASTER switch.